商务统计习题

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商务统计学复习题-统计学练习题一、单项选择题1.下列数据属于名义尺度(nominal scale)的是（）A．性别B) 年龄C)体重D)年级2.下列数据属于名义尺度(nominal scale)数据的是（）。

A．性别 B. 年龄 C. 体重 D. 年级3.下列数据属于区间尺度(order scale)数据的是（）。

A．气温 B. 产量 C. 体重 D.年级4.针对z-分数(z-score)，下列说法不正确的是（）。

A. 若z-分数小于0，则变量值小于平均数B. 若z-分数大于0，则变量值大于平均数C. 若z-分数等于0，则变量值等于平均数D. 若z-分数等于0，则变量值等于05.下列选项中，不属于变异指标(measure of variability)的是（）A) 平均数B) 极差C) 标准差D) 变异系数6.下列几种分布中，属于离散型随机变量(discrete random variable)的分布的是（）。

A. 二项分布B. 泊松分布C. 指数分布D. 超几何分布7.下列几种常见的分布中，属于连续型随机变量(continuous random variable)的分布的是（）。

A. 二项分布B. 泊松分布C. 指数分布D. 超几何分布8.一个特定研究中感兴趣的对象的全体称为（）A) 样本(sample) B) 参数(a parameter)C) 统计量(statistic)D) 总体(population)9. 下列不属于描述统计(descriptive statistics)常用形式的是（）A) 绘制图形B) 绘制表格C) 计算平均数D) 区间估计10. 下列属于统计推断(statistical inference)内容的是（）A) 绘制图形B) 绘制表格C) 计算平均数D) 区间估计11. 下列图形中，不能用于分类数据(categorical data)的是（）A)条形图B) 茎叶图C) 柱状图D) 饼状图12. 商务数据的相对频数( relative frequency)之和为（）A)1 B) 2 C) 0 D)不确定13. 若偏度=-0.85，则该组数据的分布形态为（）A)适度左偏B) 适度右偏C) 对称D) 无法确定14. 若偏度=0.85，则该组数据的分布形态为（）A.适度左偏B.适度右偏C.对称D.无法确定15.当总体服从正态分布时，样本均值x的抽样分布(sampling distribution)服从于（）。

商务统计选择答案.doc

Part One: Multiple Choices:1.The probability that a continuous random variable takes any specific valuea.is equal to zerob.is at least 0.5c.depends on the probability density functiond.is very close to 1.02. A normal distribution with a mean of 0 and a standard deviation of 1 is calleda. a probability density functionb.an ordinary normal curvec. a standard normal distributiond.none of these alternatives is correct3. A negative value of Z indicates thata.the number of standard deviations of an observation is to the right of the meanb.the number of standard deviations of an observation is to the left of the meanc. a mistake has been made in computations, since Z cannot be negatived.the data has a negative mean4.For a continuous random variable x, the probability density function f(x) representsa.the probability at a given value of xb.the area under the curve at xc.the area under the curve to the right of xd.the height of the function at x5.For the standard normal probability distribution, the area to the left of the mean isa.-0.5b.0.5c.any value between 0 to 1d. 1rger values of the standard deviation result in a normal curve that isa.shifted to the rightb.shifted to the leftc.narrower and more peakedd.wider and flatter7. A continuous probability distribution that is useful in describing the time, or space,between occurrences of an event is a(n)a.normal probability distributionb.uniform probability distributionc.exponential probability distributiond.Poisson probability distribution8.Consider a binomial probability experiment with n = 3 and p = 0.1. Then, the probabilityof x = 0 isa.0.0000b.0.0001c.0.001d.0.7299. A continuous random variable may assumea.all values in an interval or collection of intervalsb.only integer values in an interval or collection of intervalsc.only fractional values in an interval or collection of intervalsd.all the positive integer values in an interval10.The highest point of a normal curve occurs ata.one standard deviation to the right of the meanb.two standard deviations to the right of the meanc.approximately three standard deviations to the right of the meand.the meanExhibit 1The assembly time for a product is uniformly distributed between 6 to 10 minutes.11.Refer to Exhibit 1. The probability density function has what value in the interval between 6 and 10?a.0.25b. 4.00c. 5.00d.zero12.Refer to Exhibit 1. The probability of assembling the product between 7 to 9 minutes isa.zerob.0.50c.0.20d. 113.Refer to Exhibit 1. The probability of assembling the product in less than 6 minutes isa.zerob.0.50c.0.15d. 114.Refer to Exhibit 1. The probability of assembling the product in 7 minutes or more isa.0.25b.0.75c.zerod. 115.Refer to Exhibit 1. The expected assembly time (in minutes) isa.16b. 2c.8d. 416.Refer to Exhibit 1. The standard deviation of assembly time (in minutes) is approximatelya. 1.3333b. 1.1547c.0.1111d.0.577317.Center of a normal curve isa.always equal to zerob.is the mean of the distributionc.cannot be negatived.is the standard deviation18.The uniform, normal, and exponential distributions area.all continuous probability distributionsb.all discrete probability distributionsc.can be either continuous or discrete, depending on the datad.all the same distributions19.Which of the following is not a characteristic of the normal probability distribution?a.The mean, median, and the mode are equalb.The mean of the distribution can be negative, zero, or positivec.The distribution is symmetricald.The standard deviation must be 120.In a standard normal distribution, the range of values of z is froma.minus infinity to infinityb.-1 to 1c.0 to 1d.-3.09 to 3.0921.Parameters area.numerical characteristics of a sampleb.numerical characteristics of a populationc.the averages taken from a sampled.numerical characteristics of either a sample or a population22.How many simple random samples of size 3 can be selected from a population of size 7?a.7b.21c.35d.34323. A population consists of 500 elements. We want to draw a simple random sample of 50 elements from this population. On the first selection, the probability of an element being selected isa.0.100b.0.010c.0.001d.0.00224.The closer the sample mean is to the population mean,a.the larger the sampling errorb.the smaller the sampling errorc.the sampling error equals 1d.None of these alternatives is correct.25.Since the sample size is always smaller than the size of the population, the sample meana.must always be smaller than the population meanb.must be larger than the population meanc.must be equal to the population meand.can be smaller, larger, or equal to the population mean26.As the sample size increases, thea.standard deviation of the population decreasesb.population mean increasesc.standard error of the mean decreasesd.standard error of the mean increases27. A simple random sample from an infinite population is a sample selected such thata.each element is selected independently and from the same populationb.each element has a 0.5 probability of being selectedc.each element has a probability of at least 0.5 of being selectedd.the probability of being selected changes28.In point estimationa.data from the population is used to estimate the population parameterb.data from the sample is used to estimate the population parameterc.data from the sample is used to estimate the sample statisticd.the mean of the population equals the mean of the sample29.The sample mean is the point estimator ofa.pib.Gc.xd.-P30.The expected value of the random variable x isa.the standard errorb.the sample sizec.the size of the populationd.None of these alternatives is correct.31.The standard deviation of all possible x values is called thea.standard error of proportionb.standard error of the meanc.mean deviationd.central variation32.Whenever the population has a normal probability distribution, the sampling distribution of x is a normal probability distribution fora.only large sample sizesb.only small sample sizesc.any sample sized.only samples of size thirty or greater33.The sampling error is thea.same as the standard error of the meanb.difference between the value of the sample mean and the value of the population meanc.error caused by selecting a bad sampled.standard deviation multiplied by the sample size34.Which of the following is(are) point estimator(s)?a. ab.p,c.sd.a35. A population characteristic, such as a population mean, is calleda. a statisticb. a parameterc. a sampled.the mean deviation36. A single numerical value used as an estimate of a population parameter is known asa. a parameterb. a population parameterc. a mean estimatord. a point estimate37.The purpose of statistical inference is to provide information about thea.sample based upon information contained in the populationb.population based upon information contained in the samplec.population based upon information contained in the populationd.mean of the sample based upon the mean of the population38.The number of random samples (without replacement) of size 3 that can be drawn from a population of size 5 isa.15b.10c.20d.12539.For a population with any distribution, the form of the sampling distribution of the sample mean isa.sometimes normal for all sample sizesb.sometimes normal for large sample sizesc.always normal for all sample sizesd.always normal for large sample sizes40. A simple random sample of 28 observations was taken from a large population. The sample mean equaled 50. Fifty is aa.population parameterb.biased estimate of the population meanc.sample parameterd.point estimate41.When s is used to estimate G, the margin of error is computed by usinga.normal distributionb.t distributionc.the mean of the sampled.the mean of the population42.From a population with a variance of 900, a sample of 225 items is selected. At 95% confidence, the margin of error isa.15b. 2c. 3.92d. 443.In order to determine an interval for the mean of a population with unknown standard deviation a sample of 61 items is selected. The mean of the sample is determined to be 23. The number of degrees of freedom for reading the t value isa.22b.23c.60d.6144.If we want to provide a 95% confidence interval for the mean of a population, the confidence coefficient isa.0.485b. 1.96c.0.95d. 1.64545.As the number of degrees of freedom for a t distribution increases, the difference between the t distribution and the standard normal distributiona.becomes largerb.becomes smallerc.stays the samed.None of these alternatives is correct.46.For the interval estimation of p, when o is known and the sample is large, the proper distribution to use isa.the normal distributionb.the t distribution with n degrees of freedomc.the t distribution with n + 1 degrees of freedomd.the t distribution with n + 2 degrees of freedom47.An estimate of a population parameter that provides an interval of values believed to contain the value of the parameter is known as thea.confidence levelb.interval estimatec.parameter valued.population estimate48.The value added and subtracted from a point estimate in order to develop an interval estimate of the population parameter is known as thea.confidence levelb.margin of errorc.parameter estimated.interval estimate49.If an interval estimate is said to be constructed at the 90% confidence level, the confidence coefficient would bea.0.1b.0.95c.0.9d.0.0550.Whenever the population standard deviation is unknown and the population has a normal or near-normal distribution, which distribution is used in developing an interval estimation?a.standard distributionb.z distributionc.alpha distributiond.t distribution51.In interval estimation, the t distribution is applicable only whena.the population has a mean of less than 30b.the sample standard deviation is used to estimate the population standard deviationc.the variance of the population is knownd.the standard deviation of the population is known52.In developing an interval estimate, if the population standard deviation is unknowna.it is impossible to develop an interval estimateb.the standard deviation is arrived at using the rangec.the sample standard deviation can be usedd.it is assumed that the population standard deviation is 153.In order to use the normal distribution for interval estimation of)i when cr is known and the sample is very small, the populationa.must be very largeb.must have a normal distributionc.can have any distributiond.must have a mean of at least 154.From a population that is not normally distributed and whose standard deviation is not known, a sample of 6 items is selected to develop an interval estimate for the mean of the population (y).a.The normal distribution can be used.b.The t distribution with 5 degrees of freedom must be used.c.The t distribution with 6 degrees of freedom must be used.d.The sample size must be increased.55.From a population that is normally distributed, a sample of 25 elements is selected and the standard deviation of the sample is computed. For the interval estimation of pi, the proper distribution to use is thea.normal distributionb.t distribution with 25 degrees of freedomc.t distribution with 26 degrees of freedomd.t distribution with 24 degrees of freedom56.As the sample size increases, the margin of errora.increasesb.decreasesc.stays the samed.increases or decreases depending on the size of the mean57. A 95% confidence interval for a population mean is determined to be 100 to 120. If the confidence coefficient is reduced to 0.90, the interval for(ia.becomes narrowerb.becomes widerc.does not changed.becomes 0.158.The ability of an interval estimate to contain the value of the population parameter is described by thea.confidence levelb.degrees of freedomc.precise value of the population mean p,d.degrees of freedom minus 159.An interval estimate is a range of values used to estimatea.the shape of the population's distributionb.the sampling distributionc. a sample statisticd. a population parameter60.In determining the sample size necessary to estimate a population proportion, which of the following information is not needed?a.the maximum margin of error that can be toleratedb.the confidence level requiredc. a preliminary estimate of the true population proportion Pd.the mean of the population61.What type of error occurs if you fail to reject H o when, in fact, it is not true?a.Type IIb.Type Ic.either Type I or Type II, depending on the level of significanced.either Type I or Type II, depending on whether the test is one tail or two tail62.An assumption made about the value of a population parameter is called aa.hypothesisb.conclusionc.confidenced.significance63.The probability of committing a Type I error when the null hypothesis is true isa.the confidence levelb.卩c.greater than 1d.the Level of Significance64.The p-value is a probability that measures the support (or lack of support) for thea.null hypothesisb.alternative hypothesisc.either the null or the alternative hypothesisd.sample statistic65.The p-valuea.is the same as the Z statisticb.measures the number of standard deviations from the meanc.is a distanced.is a probability66.In hypothesis testing if the null hypothesis is rejected,a.no conclusions can be drawn from the testb.the alternative hypothesis is truec.the data must have been accumulated incorrectlyd.the sample size has been too small67.The level of significance is thea.maximum allowable probability of Type II errorb.maximum allowable probability of Type I errorc.same as the confidence coefficientd.same as the p-value68. A Type II error is committed whena. a true alternative hypothesis is mistakenly rejectedb. a true null hypothesis is mistakenly rejectedc.the sample size has been too smalld.not enough information has been available69.The level of significancea.can be any positive valueb.can be any valuec.is (1 - confidence level)d.can be any value between -1.96 to 1.9670.When the following hypotheses are being tested at a level of significance of aH o: pi > 500H a: ]i < 500the null hypothesis will be rejected if the p-value isa.< aH a : ]i > 10.0%H a : |i > 10.0%H a : ]i < 10.0%d. Ho ： pi > 10.0% H a : ]i < 10.0%a. Ho ： pi < 85 H a : pi > 85b. Ho ： pi < 85 H a : p, >c. Ho ： pi > 85 H a : p, < 85d. Ho ： pi > 85 H a : pi < 85 a. Ho ：pi < 12 H a : pi < 12b. Ho ： pi < 12 H a : p, >c. Ho： pi H 12H a : p, = 12b. > ac. > a/2d. < 1 - a/271. When the p-value is used for hypothesis testing, the null hypothesis is rejected if a. p-value < ab. a < p-valuec. p-value > ad. p-value = 1 - a72. In order to test the following hypotheses at an a level of significanceH o : pi < 800H a : ]i > 800the null hypothesis will be rejected if the test statistic Z isa. 巴 Z Qb. <Z ac. < -Z ad. = a73. Your investment executive claims that the average yearly rate of return on the stocks she recommends is more than 10.0%. You plan on taking a sample to test her claim. The correct setof hypotheses is a. H o : pi < 10.0% b. Ho ： pi < 10.0%c. Ho ： pi > 10.0%74. A weatherman stated that the average temperature during July in Chattanooga is less than 80 degrees. A sample of 32 Julys is taken. The correct set of hypotheses is a . H o : pi > 80 H a : p, <80 b . H o : pi < 80 H a : p, >80 c . H o : —80 H a : p, =80 d . H o : pi < 80 H a : p, >80 75. A student believes that the average grade on the final examination in statistics is at least85. She plans on taking a sample to test her belief. The correct set of hypotheses is76. A soft drink filling machine, when in perfect adjustment, fills the bottles with 12 ouncesof soft drink. Any over filling or under filling results in the shutdown and readjustment of the machine. To determine whether or not the machine is properly adjusted, the correct set ofhypotheses is d. Ho ： p = 1277. A two-tailed test is performed at 95% confidence. The p-value is determined to be 0.09. The null hypothesisa.must be rejectedb.should not be rejectedc . could be rejected, depending on the sample sized . has been designed incorrectly7 8Exhibit 2n = 49 x = 54.8 s = 28 H o: pi < 50H a: p, > 50Refer to Exhibit 2. The test statistic isa . 0.1714b . 0.3849c . -1.2d . 1.27 9Refer to Exhibit 2. The p-value is betweena . 0.01 to 0.025b . 0.025 to 0.05c . .05 to 0.1d . 0.1 to 0.28 0Refer to Exhibit 2. If the test is done at the 5% level of significance, the null hypothesisshoulda . not be rejectedb . be rejectedc . Not enough information given to answer this question.d . None of these alternatives is correct.8 1If we are interested in testing whether themeanof population 1 is significantly largerthanthe mean of population 2, thea . null hypothesis should state 内-应 > 0b . null hypothesis should state 内-应巴0c . alternative hypothesis should state p，i - |i2 > 0d . alternative hypothesis should state pii -112 < 08 2If we are interested in testing whether themeanof population 1 is significantlydifferentfrom the mean of population 2, thea . null hypothesis should state 山-应=0b . null hypothesis should state 山-应巴0c . alternative hypothesis should state p，i - |i2 > 0d . alternative hypothesis should state pii -112 < 08 3When developing an interval estimate for the difference between two sample means, withsample sizes of m and n2,a . Ni must be equal to n2b . Ni must be smaller than n2c . Ni must be larger than n2d . Ni and n2 can be of different sizes,84.Independent simple random samples are taken to test the difference between the means of two populations whose variances are not known, but are assumed to be equal. The samplesizes are m = 32 and n2 = 40. The correct distribution to use is thea.t distribution with 73 degrees of freedomb.t distribution with 72 degrees of freedomc.t distribution with 71 degrees of freedomd.t distribution with 70 degrees of freedom85.If two independent large samples are taken from two populations, the sampling distribution of the difference between the two sample meansa.can be approximated by a Poisson distributionb.will have a variance of onec.can be approximated by a normal distributiond.will have a mean of one86.The standard error of x -x2 is thea.--variance of x 严Qb.--variance of the sampling distribution of 区厂乂？c.- ~standard deviation of the sampling distribution of x 严？d.difference between the two means87.In the analysis of variance procedure (ANOVA), ''factor'' refers toa.the dependent variableb.the independent variablec.different levels of a treatmentd.the critical value of F88.The ANOVA procedure is a statistical approach for determining whether or nota.the means of two samples are equalb.the means of two or more samples are equalc.the means of more than two samples are equald.the means of two or more populations are equal89.An experimental design where the experimental units are randomly assigned to the treatments is known asa.factor block designb.random factor designpletely randomized designd.None of these alternatives is correct.90.In an analysis of variance problem involving 3 treatments and 10 observations per treatment, SSE = 399.6. The MSE for this situation isa.133.2b.199.8c.14.8d.30.04 4 4 191.The F ratio in a completely randomized ANOVA is the ratio ofa.MSTR/MSEb.MST/MSEc.MSE/MSTRd.MSE/MST92.The critical F value with 6 numerator and 60 denominator degrees of freedom at a = .05 isa. 3.74b. 2.25c. 2.37d. 1.9693.An ANOVA procedure is applied to data obtained from 6 samples where each sample contains 20 observations. The degrees of freedom for the critical value of F area. 6 numerator and 20 denominator degrees of freedomb. 5 numerator and 20 denominator degrees of freedomc. 5 numerator and 114 denominator degrees of freedomd. 6 numerator and 20 denominator degrees of freedom94.In an analysis of variance problem if SST = 120 and SSTR = 80, then SSE isa.200b.40c.80d.12095.An ANOVA procedure is used for data that was obtained from four sample groups each comprised of five observations. The degrees of freedom for the critical value of F area. 3 and 20b. 3 and 16c. 4 and 17d. 3 and 1996.In ANOVA, which of the following is not affected by whether or not the population means are equal?a.xb.between-samples estimate of c>2c.within-samples estimate of c>2d.None of these alternatives is correct.97. A term that means the same as the term "variable" in an ANOVA procedure isa.factorb.treatmentc.replicationd.variance withinExhibit 3Salary information regarding male and female employees of a large company is shown below.Male FemaleSample Size 64 36Sample Mean Salary (in $1,000)Population Variance (cr2) 128 7298.Refer to Exhibit 3. The point estimate of the difference between the means of the two populations isa.-28b. 3c. 4d.-499.Refer to Exhibit 3. The standard error for the difference between the two means isa. 4b.7.46c. 4.24d. 2.0100.Refer to Exhibit 3. At 95% confidence, the margin of error isa. 1.96b. 1.645c. 3.920d. 2.000101.The coefficient of determinationa.cannot be negativeb.is the square root of the coefficient of correlationc.is the same as the coefficient of correlationd.can be negative or positive102.If the coefficient of determination is a positive value, then the coefficient of correlationa.must also be positiveb.must be zeroc.can be either negative or positived.must be larger than 1103.The mathematical equation relating the independent variable to the expected value of the dependent variable; that is, E(y) = P0 + 卩lx, is known asa.regression equationb.correlation equationc.estimated regression equationd.regression model104.The model developed from sample data that has the form of y = + ijX is known asa.regression equationb.correlation equationc.estimated regression equationd.regression model105.The interval estimate of the mean value of y for a given value of x isa.prediction interval estimateb.confidence interval estimatec.average regressiond.x versus y correlation interval106.The interval estimate of an individual value of y for a given value of x isa.prediction interval estimateb.confidence interval estimatec.average regressiond.x versus y correlation interval107.In a regression analysis the standard error is determined to be 4. In this situation the MSEa.is 2b.is 16c.depends on the sample sized.depends on the degrees of freedom108.In regression analysis, which of the following is not a required assumption about the error term £?a.The expected value of the error term is one.b.The variance of the error term is the same for all values of X.c.The values of the error term are independent.d.The error term is normally distributed.109.In a regression analysis, the coefficient of determination is 0.4225. The coefficient of correlation in this situation isa.0.65b.0.1785c.any positive valued.any value110.In a regression analysis, the coefficient of correlation is 0.16. The coefficient of determination in this situation isa.0.4000b.0.0256c. 4d. 2.56111.In a regression and correlation analysis if r2 = 1, thena.SSE must also be equal to oneb.SSE must be equal to zeroc.SSE can be any positive valued.SSE must be negative112.In a regression and correlation analysis if r2 = 1, thena.SSE = SSTb.SSE= 1c.SSR = SSEd.SSR = SST113.If the coefficient of correlation is a positive value, then the regression equationa.must have a positive slopeb.must have a negative slopec.could have either a positive or a negative sloped.must have a positive y intercept114.If the coefficient of correlation is 0.& the percentage of variation in the dependent variable explained by the variation in the independent variable isa.0.80%b.80%c.0.64%d.64%115.In regression and correlation analysis, if SSE and SST are known, then with this information thea.coefficient of determination can be computedb.slope of the line can be computedc.Y intercept can be computedd.x intercept can be computed116.In regression analysis, if the independent variable is measured in pounds, the dependent variablea.must also be in poundsb.must be in some unit of weightc.cannot be in poundsd.can be any units117.If the coefficient of correlation is -0.4, then the slope of the regression linea.must also be -0.4b.can be either negative or positivec.must be negatived.must be 0.16118.If the coefficient of correlation is a negative value, then the coefficient of determinationa.must also be negativeb.must be zeroc.can be either negative or positived.must be positive119.If a data set has SSR = 400 and SSE = 100, then the coefficient of determination isa.0.10b.0.25c.0.40d.0.80pared to the confidence interval estimate for a particular value of y (in a linear regression model), the interval estimate for an average value of y will bea.narrowerb.widerc.the samed.None of these alternatives is correct.。

《商务统计学》题集

《商务统计学》题集一、选择题（每题2分，共10分）1.下列哪项不属于商务统计学的应用范围？A. 市场调查B. 质量控制C. 财务分析D. 天气预测2.在统计学中，总体是指什么？A. 研究的全部对象B. 研究中的一部分对象C. 某个具体的样本D. 某一特定数据3.下列哪种抽样方法是随机抽样？A. 方便抽样B. 系统抽样C. 配额抽样D. 判断抽样4.如果一组数据的均值是20，中位数是22，那么这组数据的分布可能是？A. 正偏态B. 负偏态C. 对称分布D. 无法确定5.在回归分析中，解释变量和被解释变量分别是什么？A. 因变量和自变量B. 自变量和因变量C. 都是自变量D. 都是因变量二、填空题（每空1分，共10分）1.在统计学中，用来衡量数据分布集中趋势的指标有______、______和______。

2.若一组数据的四分位数Q1=10，Q2=20，Q3=30，则该组数据的中位数为______。

3.在假设检验中，如果P值小于显著性水平α，则我们______原假设。

4.统计表中，频数和频率分别表示数据的______和______。

5.在回归分析中，回归系数的经济意义是解释变量每增加一个单位，被解释变量平均增加______单位。

三、判断题（每题1分，共10分）1.统计学的目的是收集、整理、分析和解释数据，从而帮助人们做出决策。

（）2.在正态分布中，均值、中位数和众数三者相等。

（）3.标准差是衡量数据波动大小的一个重要指标，标准差越大，说明数据的波动越大。

（）4.在假设检验中，如果P值大于显著性水平α，则我们有足够的证据拒绝原假设。

（）5.相关系数r的取值范围是[-1, 1]，r=1表示完全正相关，r=-1表示完全负相关。

（）6.如果一组数据的偏度系数大于0，则说明这组数据是正偏态分布。

（）7.在抽样调查中，样本容量越大，抽样误差就越小。

（）8.统计推断是通过样本数据来推断总体的特征。

（）9.移动平均法是一种常用的时间序列预测方法。

商务经济统计试题及答案

商务经济统计试题及答案一、单项选择题1. 商务统计中，用于描述数据集中趋势的指标是：A. 方差B. 标准差C. 平均数D. 众数答案：C2. 在商务经济统计中，下列哪项不是统计量？A. 均值B. 标准差C. 样本容量D. 极差答案：C3. 以下哪项不是时间序列分析的类型？A. 季节性分析B. 趋势分析C. 相关性分析D. 循环分析答案：C二、多项选择题1. 商务统计中，以下哪些因素会影响数据的变异性？A. 数据的分布形态B. 数据的集中趋势C. 数据的离散程度D. 数据的样本大小答案：A、C2. 在进行商务经济预测时，常用的统计方法包括：A. 回归分析B. 指数平滑法C. 移动平均法D. 季节性调整答案：A、B、C三、简答题1. 简述商务统计中的指数平滑法的基本原理。

答案：指数平滑法是一种时间序列预测方法，它通过对历史数据加权平均来预测未来值。

权重随着时间的递减而递减，即近期的数据比远期的数据在预测中占有更大的权重。

这种方法可以平滑掉数据中的随机波动，从而更好地反映数据的趋势。

2. 描述商务统计中相关系数的计算方法及其意义。

答案：相关系数是用来衡量两个变量之间线性关系强度和方向的统计量。

其计算公式为：\[ r = \frac{\sum (X_i - \bar{X})(Y_i -\bar{Y})}{\sqrt{\sum (X_i - \bar{X})^2 \sum (Y_i -\bar{Y})^2}} \] 其中，$ X_i $ 和 $ Y_i $ 分别是两个变量的观测值，$ \bar{X} $ 和 $ \bar{Y} $ 是它们的平均值。

相关系数的值介于-1和1之间，值越接近1或-1表示变量间的线性关系越强，正值表示正相关，负值表示负相关。

四、计算题1. 假设有一组商务数据，其平均值为100，标准差为15。

如果某次测量结果为120，计算该结果的Z分数。

答案：Z分数的计算公式为：\[ Z = \frac{(X - \mu)}{\sigma} \]其中，$ X $ 是测量结果，$ \mu $ 是平均值，$ \sigma $ 是标准差。

商务统计试题5精选全文

精选全文完整版（可编辑修改）《商务统计》试题5------------------------------------------------------------------------------------------------------------------------一、判断题（每题1分，共10分）1.应用切比雪夫定理估计与平均数的距离在z个标准差之内的数据项所占比例时，z的取值可以是任意正数( )。

2.条形图和直方图都可以用于描述分类数据的频数分布、相对频数分布或百分比频数分布( )。

3.在样本容量一定的情况下，为了确保更高的置信度，置信区间的宽度必须变大( )。

4.事件A与其补A c是互斥的( )。

5.无论是单侧检验还是双侧检验，如果p值≤α，则拒绝原假设H0( )。

6.对于简单随机样本，样本均值x̅的数学期望、标准差受到样本容量n的影响 ( )。

7.在联列表中，两个变量必须都是分类变量或者都是数值型变量( )。

8.当分类数据用数值表示时，可以进行有意义的算术运算( )。

9.在满足一定条件时，可以用正态分布近似计算二项分布 ( )。

10.方差分析仅能用于实验性研究得到的数据而不能用于观测性研究得到的数据( )。

二、单项选择题（每题2分，共30分）1.由于改变生产方法所需的时间和成本都很大，所以在一种新方法实施之前，制造负责人必须使管理人员确信，推荐的制造方法能降低成本。

目前生产方法的平均成本是每小时22美元。

一项调研工作是在样本生产期同，测量新方法的成本。

以下假设合适的是( )。

A. H0:μ≥22 H a:μ<22B.H0:μ≤22 H a:μ>22C.H0:μ>22 H a:μ≤22D.H0:μ<22 H a:μ≥222.以下关于众数的说法错误的是( )。

A.众数是数据集中出现频率最高的数据值B.众数仅适用于数值型数据C.众数是一种位置度量指标D.众数有可能存在两个或更多3.以下关于事件的概率说法错误的是( )。

商务统计试题及答案

商务统计试题及答案### 商务统计试题及答案#### 一、选择题1. 统计数据收集的方法不包括以下哪项？- A. 观察法- B. 实验法- C. 调查法- D. 假设法答案：D2. 以下哪项不是描述性统计分析的内容？- A. 数据的分类- B. 数据的汇总- C. 数据的推断- D. 数据的图表展示答案：C3. 在统计学中，中位数是指：- A. 数据集中出现次数最多的数值- B. 数据集的算术平均值- C. 将数据集从小到大排列后位于中间位置的数值 - D. 所有数据的和除以数据的个数答案：C#### 二、简答题1. 解释什么是标准差，并简述其在商务统计中的重要性。

标准差是衡量一组数据离散程度的统计量，它表示数据集中的数值与平均值的偏差平方的平均数的平方根。

在商务统计中，标准差用于评估数据的波动性，帮助决策者了解业务风险和市场波动。

2. 描述相关系数的概念及其在商务分析中的应用。

相关系数是度量两个变量之间线性关系强度和方向的统计指标。

在商务分析中，相关系数可以用来评估不同因素对业务结果的影响，例如，销售额与广告支出之间的关系。

#### 三、计算题1. 给定以下数据集：10, 12, 15, 20, 25, 请计算平均值、中位数和标准差。

- 平均值 = (10 + 12 + 15 + 20 + 25) / 5 = 18- 中位数 = 15（数据集从小到大排列后位于中间位置的数值）- 标准差= √[(Σ(xi - 平均值)²) / n] = √[(10 - 18)² + (12 - 18)² + ... + (25 - 18)²] / 5 ≈ 5.392. 假设某公司连续5个月的销售额分别为：30万、35万、40万、45万和50万。

计算这5个月的平均销售额和销售额的增长趋势。

- 平均销售额 = (30 + 35 + 40 + 45 + 50) / 5 = 40万- 销售额的增长趋势可以通过计算每月销售额的增长率来分析，例如，从第一个月到第二个月的增长率为 (35 - 30) / 30 * 100% = 16.67%。

商务统计复习题集.doc

商务统计复习题集《商务统计习题》一CZW1一、单选题；1、在数据采集活动中，进行观测记录的基本单位与总体屮的个体（）。

A、必须相同B、必须不同C、可以相同，也可以不同D、完全没有关系2、对于内部差异很大口有明显的不同类型界限或标志的总体，进行抽样调查应该采用的抽样方式是（）。

A、简单随机抽样B、系统抽样C、分层抽样D、整群抽样3、构成次数分布表的基本要素是（）oA、各个个体的名称与指标数值B、各组变量值与次数C、各组变量值与其方差D、各组均值与方差4、如果观测变量的取值很多且数值成比例变化，则编制次数分布表时采用（）。

A、单值B、等距分组C、异距分组D、复合分组5、统计指标是用来测度统计活动研究对象某种特征数量的（）。

《商务统计习题》一czw2A、概念B、数值C、概念和数值D、数值尺度6、统计指标口径是指统计指标所包括的（）。

A、总体大小B、个体多少C、理论范围D、具体范围7、统计推断是一种（）。

A、演绎推理B、完全归纳推理C、不完全归纳推理D、非逻辑推理。

8、根据斯特吉斯公式，对于样本容量为1000的一个观测样本，采用等距分组，英组数应该为（）。

A、9 组B、10 组C、11 组D、12 组9、从0-1分布总体屮进行不放回抽样，样本屮具有1值的个体数服从（）。

A、两点分布B、二项分布C、超几何分布D、泊松分布10、对于由观测变量的各个分组和各组变量总值顺序排列的分组分布表，计算算术平均数需采用的计算公式为（）0A、简单算术平均数B、加权算术平均数C、简单调和平均数D、加权调和平均数口、随机变量的观测值中出现次数最多的变量值是该变量的（）oA、众数B、中位数C、极值D、均值12、两个观测值之间如果存在同方向的线性函数关系，则二者的相关关系为（）。

A、0B、1C、-1D、0.5)o15、变量x 和y 的相关系数的符号，取决于（）。

A 、正态分布B 、x 分布C 、t 分布D 、均匀分布2 18、抽样分布是指（ )oA 、抽取样本的总体分布B 、样本自身的分布C 、样本统计量的分布D 、抽样观测变量的分布估计量是一个（）。

商务统计学试题

商务统计学[单项选择题]1、在数据采集活动中，进行观测记录的单位与总体中的个体（）A.必须相同B.必须不同C.可以相同，也可以不同D.完全没有关系参考答案：C[单项选择题]2、对于内部差异很大且有明显的不同类型界限或标志的总体，进行抽样调查应该采用的抽样方式是（）A.简单随机抽样B.系统抽样C.分层抽样D.整群抽样参考答案：C[单项选择题]3、如果观测变量的取值很多且数值成比例变化，则编制次数分布表时采用（）A.单值B.等距分组C.异距分组D.复合分组参考答案：C[单项选择题]4、统计指标是用来测度统计活动研究对象某种特征数量的（）A.概念B.数值C.概念和数值D.数值尺度参考答案：A[单项选择题]5、统计推断是一种（）A.演绎推理B.完全归纳推理C.不完全归纳推理D.非逻辑推理参考答案：C[单项选择题]6、根据斯特吉斯公式，对于样本容量为1000的一个观测样本，采用等距分组，其组数应该为（）A.9组B.10组C.11组D.12组参考答案：C[单项选择题]7、对于由观测变量的各个分组和各组变量总值顺序排列的分组分布表，计算算术平均数需采用的计算公式为（）A.简单算术平均数B.加权算术平均数C.简单调和平均数D.加权调和平均数参考答案：D[单项选择题]8、随机变量的观测值中出现次数最多的变量值是该变量的（）A.众数B.中位数C.极值D.均值参考答案：A[单项选择题]9、两个观测值之间如果存在同方向的线性函数关系，则二者的相关关系为（）A.0B.1C.-1D.0.5参考答案：B[单项选择题]10、对于同一数据，所计算出的平均差与标准差相比，通常有（）A.平均差大于标准差B.平均差小于标准差C.平均差等于标准差D.二者关系不定参考答案：B[单项选择题]11、变量x和y的相关系数的符号，取决于（）A.变量x的标准差B.变量y的标准差C.变量x和y两个标准差的乘积D.变量x和y的协方差参考答案：D[单项选择题]12、对于从所考察总体中随机抽取的一个大样本，其样本均值近似服从（）A.正态分布B.x2分布C.t分布D.均匀分布参考答案：A[单项选择题]13、抽样分布是指（）A.抽取样本的总体分布B.样本自身的分布C.样本统计量的分布D.抽样观测变量的分布参考答案：C[单项选择题]14、如果θ^是该参数θ的一致估计，则随着样本容量n的增大，有（）A.θ^的数值接近于总体参数θB.θ^的期望等于总体参数θC.θ^的方差接近于总体参数θD.θ^的方差接近于总体方差σ2参考答案：A[单项选择题]15、在假设检验中，犯第一类错误的概率等于（）A.αB.βC.1－αD.1－β参考答案：A[单项选择题]16、在给定的显著性水平之下，进行假设检验，确定拒绝域的依据是（）A.原假设为真的条件下检验统计量的概率分布B.备择假设为真的条件下检验统计量的概率分布C.观测变量的总体概率分布D.观测变量的样本分布参考答案：A[单项选择题]17、在单因子方差分析中，如果各个因子水平效应相同的原假设为真，则组间平方和SSA（）A.等于0B.等于总平方和C.完全由观测的随机误差引起D.完全由各因子水平的差异引起参考答案：C[单项选择题]18、在方差分析中，所考察的影响观测变量的各个因子都必须（）A.属性化B.数量化C.同质化D.差异化参考答案：A[单项选择题]19、使用最小二乘法估计得出的样本回归直线必然通过点（）A.（0，0）B.（x，0）C.（0，y）D.（x，y）参考答案：D[单项选择题]20、居民家庭人均消费支出的差异随着家庭人均收入的提高而增加，这种现象称为（）A.直线趋势B.曲线趋势C.异方差D.异常数据参考答案：C[单项选择题]21、累计采样所得到的时间序列是（）A.时点序列B.时期序列C.特征序列D.平稳序列参考答案：B更多内容请访问《睦霖题库》微信公众号[单项选择题]22、已知一个时间序列的最初水平和最末水平，要计算各期的平均增长速度，则应采用的计算方法为（）A.算术平均法B.几何平均法C.代数平均法D.调和平均法参考答案：B[单项选择题]23、如果时间序列的环比增长量大致相等，则应采用的趋势模型为（）A.直线趋势模型B.指数曲线趋势模型C.二次曲线趋势模型D.修正指数曲线趋势模型参考答案：A[单项选择题]24、非概率型决策是一种（）A.确定性决策B.非确定性决策C.等可能性决策D.非计算性决策参考答案：B[单项选择题]25、期望损益准则特别适用于（）A.重复性决策B.一次性决策C.确定性决策D.非概率型决策参考答案：A[单项选择题]26、劳动生产率指数是一个（）。

商务经济统计试题及答案

商务经济统计试题及答案一、单项选择题（每题2分，共20分）1. 商务经济统计的主要研究对象是什么？A. 社会经济现象B. 社会文化现象C. 自然现象D. 政治现象答案：A2. 下列哪项不是统计数据的来源？A. 人口普查B. 社会调查C. 历史记录D. 个人猜测答案：D3. 在商务经济统计中，下列哪项是描述性统计分析的内容？A. 预测未来趋势B. 描述数据特征C. 制定政策D. 进行假设检验答案：B4. 统计学中的“参数”是指什么？A. 样本数据B. 总体数据C. 样本容量D. 总体数量答案：B5. 以下哪个概念不是概率论的基本概念？A. 随机事件B. 概率C. 总体D. 样本答案：C6. 商务经济统计中，平均数通常用来衡量数据的什么？A. 集中趋势B. 离散程度C. 偏态分布D. 正态分布答案：A7. 在统计学中，标准差是用来衡量什么的？A. 集中趋势B. 离散程度C. 平均值D. 偏态分布答案：B8. 下列哪项是统计学中用于描述数据分布形状的指标？A. 平均数B. 标准差C. 众数D. 方差答案：C9. 在商务经济统计中，相关系数的取值范围是多少？A. -1到1B. 0到1C. 1到10D. -10到10答案：A10. 以下哪种图表最适合展示时间序列数据？A. 条形图B. 饼图C. 折线图D. 散点图答案：C二、多项选择题（每题3分，共15分）1. 商务经济统计中常用的数据收集方法包括哪些？A. 问卷调查B. 观察法C. 实验法D. 抽样调查答案：ABD2. 下列哪些是描述数据集中趋势的统计量？A. 平均数B. 中位数C. 众数D. 方差答案：ABC3. 在商务经济统计中，下列哪些因素会影响数据的代表性？A. 样本容量B. 抽样方法C. 样本误差D. 总体大小答案：AB4. 统计学中，下列哪些方法可以用来检验假设？A. t检验B. 卡方检验C. 回归分析D. 方差分析答案：ABD5. 在商务经济统计中，下列哪些图表可以用来展示数据的分布？A. 条形图B. 直方图C. 箱线图D. 散点图答案：ABC三、简答题（每题5分，共20分）1. 简述商务经济统计在企业决策中的作用。

商务统计试题及答案

商务统计试题及答案一、单项选择题（每题2分，共20分）1. 商务统计中，数据的收集方法不包括以下哪一项？A. 观察法B. 实验法C. 调查法D. 推算法答案：D2. 在统计学中，总体是指：A. 研究对象的全体B. 研究对象的一部分C. 研究对象的个体D. 研究对象的样本答案：A3. 下列哪个选项不是描述数据集中趋势的统计量？A. 平均数B. 中位数C. 方差D. 众数答案：C4. 在商务统计中，相关系数的取值范围是：A. -1到1之间B. 0到1之间C. 1到10之间D. 任何实数答案：A5. 以下哪种图表最适合展示时间序列数据的变化趋势？A. 条形图B. 饼图C. 折线图D. 散点图答案：C6. 假设检验的目的是：A. 确定总体参数B. 估计总体参数C. 验证样本数据D. 验证总体参数答案：D7. 在回归分析中，自变量和因变量之间的关系是：A. 正相关B. 负相关C. 无关D. 线性关系答案：D8. 下列哪个选项不是统计分析中常见的数据类型？A. 定类数据B. 定序数据C. 定距数据D. 定性数据答案：D9. 标准差是衡量数据离散程度的统计量，其计算公式为：A. 平均数的平方B. 平均数的平方根C. 方差的平方根D. 方差的倒数答案：C10. 以下哪个统计量用于衡量数据的偏态？A. 均值B. 方差C. 偏度D. 峰度答案：C二、多项选择题（每题3分，共15分）1. 下列哪些是商务统计中常用的数据收集方法？A. 观察法B. 实验法C. 调查法D. 推算法答案：ABC2. 在商务统计中，描述数据集中趋势的统计量包括：A. 平均数B. 中位数C. 方差D. 众数答案：ABD3. 以下哪些是描述数据离散程度的统计量？A. 标准差B. 方差C. 偏度D. 峰度答案：AB4. 在统计学中，总体参数和样本统计量的区别在于：A. 总体参数是固定的B. 样本统计量是估计值C. 总体参数是估计值D. 样本统计量是固定的答案：AB5. 下列哪些是商务统计中常见的数据类型？A. 定类数据B. 定序数据C. 定距数据D. 定性数据答案：ABC三、判断题（每题2分，共10分）1. 商务统计中，数据收集的方法只有调查法和观察法。

商务统计期末试题及答案

商务统计期末试题及答案【注意：以下为示例文章格式，实际内容与题目无关】一、选择题（每题2分，共30分）1. 下面哪个选项是正确的？A. 1+1=2B. 1+1=3C. 1+1=4D. 1+1=5答案：A2. 给定数据集的平均值为5，标准差为2，那么方差为多少？A. 1B. 2C. 4D. 8答案：C二、判断题（每题2分，共20分）1. 描述性统计是通过样本数据推断总体特征的方法。

答案：正确2. 概率分布函数可以描述随机变量的所有可能取值的概率。

答案：正确三、计算题1. 一个班级有30名学生，其中男生有20名，女生有10名。

请计算男生人数占总人数的比例，并将结果四舍五入到小数点后两位。

答案：20 / 30 = 0.67，四舍五入为 0.672. 有一个餐厅，星期一到星期五的销售额分别为1000、1500、1200、800、2000元，请计算平均销售额。

答案：(1000 + 1500 + 1200 + 800 + 2000) / 5 = 1100元3. 一家公司销售了3种产品，产品A的销售额占总销售额的30%，产品B的销售额占总销售额的40%，产品C的销售额为2000元，求总销售额。

答案：产品C的销售额占总销售额的30% + 40% = 70%，则总销售额为2000元 / 70% = 2857.14元四、应用题某公司进行了一次市场调研，调查了1000名顾客的购买行为。

以下是调查结果：- 500人购买了产品A- 300人购买了产品B- 200人购买了产品C- 100人购买了产品A和产品B- 50人购买了产品B和产品C- 20人购买了产品A和产品C- 10人购买了三种产品请回答以下问题：1. 购买了产品A但未购买产品B的顾客有多少人？答案：购买了产品A的人数减去购买了产品A和产品B的人数：500 - 100 = 400人2. 购买了产品B且同时购买了产品C的顾客有多少人？答案：购买了产品B和产品C的人数：50人3. 购买了至少一种产品的顾客有多少人？答案：购买了产品A、B或C的人数加上购买了三种产品的人数：500 + 300 + 200 - 10 = 990人五、简答题1. 请解释什么是样本调查？答：样本调查是从总体中选取一部分样本，并对这些样本进行调查和研究，通过对样本的观察和分析来推断总体的特征和规律。

商务统计习题.doc

简答题：1.什么是分层抽样、系统（等距）抽样？（含义、例子）（1）分层抽样：先将总体的单位按某种特征分为若干次级总体（层），然后再从每一层内进行单纯随机抽样，组成-个样木。

例：假设某地区有高中生1200人，初中生2400人，小学生4800人，此地教育部门为了了解本地区学生近视情况，从中抽取100名学生进行调杳。

例：在以学校进行抽样调查,可先把总体分为男生和女生，然后，采用简单随机抽样方法或系统抽样的方法，分别从男生和女生中各抽100名，这样，由这200名学生所构成的就是一个由分成抽样所得到的样木。

（2）系统抽样：将总体各单位按某一标志顺序排队，然后按照一定的间隔抽取样木单位。

例：耍从某校的10000名学生屮抽取100个进行健康检查，由于总体屮个体数比较多，采用系统扌山样。

例：和合用'总体及样木规模都较大的情况。

它与简单随机抽样-•样都要有完整的抽样框。

比如在3000名学生中抽取100名，则先将这3000名的名单依次编上编号，再根据公式K （抽样间距）=N （总体规模）/n （样本规模）二3000/100二30, 即每隔30名抽1名。

2•什么是区间估计？影响区间估计长度的因素有哪些？所谓区间估计，就是在点估计的基础上，用一个具有一定可靠程度的区间范围来估计总体参数。

记总体指标为0,样本估计量为0,事先给定概率为1-a ,若根据样本估计量的概率分布可计算出一个区间（玄,玄），使得该区间包含总体参数0的概率等于事先给定的概率1-a ,即有：P®a,则该区成立，就该区间（玄，4）称为总体参数°的置信区间，而概率1-«就称为是置信概率或置信度。

影响因素：总体标准弟、所要求置信水平、样木容量3•什么是假设检验的P值？使用P值检验的程序有哪些（基本步骤）？检验统计量的取值落在其实际样本值之外的概率，就称为假设检验的p值。

程序：⑴提出原假设HO和备择假设H1；（2）规定检验的显著性水平u :（3）构造用于检验的样本指标，即检验统计量；（4）在原假设为真的假定下，根据检验统计量的概率分布，确定出检验统计量的临界值，并由此临界值构造出检验的拒绝域和接受域；或者计算出假设检验的p值；⑸比较检验统计量的实际样木值与其临界值，或者比较检验的p值与显著性水平a ,并根据比较的结果做出拒绝或不能拒绝原假设的决策。

商务统计学习题

CHAPTER 1—DATA AND STATISTICSMULTIPLE CHOICE1. In a questionnaire, respondents are asked to mark their gender as male or female. Gender is an exampleof thea. ordinal scaleb. nominal scalec. ratio scaled. interval scaleANS: B PTS: 1 TOP: Descriptive Statistics2. The nominal scale of measurement has the properties of thea. ordinal scaleb. only interval scalec. ratio scaled. None of these alternatives is correct.ANS: D PTS: 1 TOP: Descriptive Statistics3. The scale of measurement that is used to rank order the observation for a variable is called thea. ratio scaleb. ordinal scalec. nominal scaled. interval scaleANS: B PTS: 1 TOP: Descriptive Statistics4. Some hotels ask their guests to rate the hotel's services as excellent, very good, good, and poor. This is anexample of thea. ordinal scaleb. ratio scalec. nominal scaled. interval scaleANS: A PTS: 1 TOP: Descriptive Statistics5. The ordinal scale of measurement has the properties of thea. ratio scaleb. interval scalec. nominal scaled. ratio and interval scalesANS: C PTS: 1 TOP: Descriptive Statistics6. The ratio scale of measurement has the properties ofa. only the ordinal scaleb. only the nominal scalec. the rank scaled. the interval scaleANS: D PTS: 1 TOP: Descriptive Statistics7. Temperature is an example of a variable that usesa. the ratio scaleb. the interval scalec. the ordinal scaled. either the ratio or the ordinal scaleANS: B PTS: 1 TOP: Descriptive Statistics8. The interval scale of measurement has the properties of thea. ratio and nominal scalesb. ratio and ordinal scalesc. ratio scaled. None of these alternatives is correct.ANS: D PTS: 1 TOP: Descriptive Statistics9. Arithmetic operations are inappropriate fora. the ratio scaleb. the interval scalec. both the ratio and interval scalesd. the nominal scaleANS: D PTS: 1 TOP: Descriptive Statistics10. Income is an example of a variable that uses thea. ratio scaleb. interval scalec. nominal scaled. ordinal scaleANS: A PTS: 1 TOP: Descriptive Statistics11. Data obtained from a nominal scalea. must be alphabeticb. can be either numeric or nonnumericc. must be numericd. must rank order the dataANS: B PTS: 1 TOP: Descriptive Statistics12. The scale of measurement that has an inherent zero value defined is thea. ratio scaleb. nominal scalec. ordinal scaled. interval scaleANS: A PTS: 1 TOP: Descriptive Statistics13. Arithmetic operations are appropriate fora. only the ratio scaleb. only the interval scalec. the nominal scaled. None of these alternatives is correct.ANS: D PTS: 1 TOP: Descriptive Statistics14. Quantitative data refers to data obtained with a(n)a. ordinal scaleb. nominal scalec. either interval or ratio scaled. only interval scaleANS: C PTS: 1 TOP: Descriptive Statistics15. Dataa. are always be numericb. are always nonnumericc. are the raw material of statisticsd. None of these alternatives is correct.ANS: C PTS: 1 TOP: Descriptive Statistics16. The entities on which data are collected area. elementsb. populationsc. samplesd. None of these alternatives is correct.ANS: A PTS: 1 TOP: Descriptive Statistics17. The set of measurements collected for a particular element is (are) calleda. variablesb. observationsc. samplesd. None of these alternatives is correct.ANS: B PTS: 1 TOP: Descriptive Statistics18. A characteristic of interest for the elements is called a(n)a. sampleb. data setc. variabled. None of these alternatives is correct.ANS: C PTS: 1 TOP: Descriptive Statistics19. All the data collected in a particular study are referred to as thea. inferenceb. variablec. data setd. None of these alternatives is correct.ANS: C PTS: 1 TOP: Descriptive Statistics20. Another name for "observations" isa. viewsb. variablesc. casesd. None of these alternatives is correct.ANS: C PTS: 1 TOP: Descriptive Statistics21. Quantitative dataa. are always nonnumericb. may be either numeric or nonnumericc. are always numericd. None of these alternatives is correct.ANS: C PTS: 1 TOP: Descriptive Statistics22. In a questionnaire, respondents are asked to mark their gender as male or female. Gender is an exampleof aa. qualitative variableb. quantitative variablec. qualitative or quantitative variable, depending on how the respondents answered thequestiond. None of these alternatives is correct.ANS: A PTS: 1 TOP: Descriptive Statistics23. The number of cases will always be the same as the number ofa. variablesb. elementsc. data setsd. dataANS: B PTS: 1 TOP: Descriptive Statistics24. Qualitative dataa. must be numericb. must be nonnumericc. cannot be numericd. may be either numeric or nonnumericANS: D PTS: 1 TOP: Descriptive Statistics25. Qualitative dataa. indicate either how much or how manyb. cannot be numericc. are labels used to identify attributes of elementsd. must be nonnumericANS: C PTS: 1 TOP: Descriptive Statistics26. Ordinary arithmetic operations are meaningfula. only with qualitative datab. only with quantitative datac. either with quantitative or qualitative datad. None of these alternatives is correct.ANS: B PTS: 1 TOP: Descriptive Statistics27. Social security numbers consist of numeric values. Therefore, social security is an example ofa. a quantitative variableb. either a quantitative or a qualitative variablec. an exchange variabled. a qualitative variableANS: D PTS: 1 TOP: Descriptive Statistics28. Temperature is an example ofa. a qualitative variableb. a quantitative variablec. either a quantitative or qualitative variabled. neither a quantitative nor qualitative variableANS: B PTS: 1 TOP: Descriptive Statistics29. For ease of data entry into a university database, 1 denotes that the student is an undergraduate and 2indicates that the student is a graduate student. In this case data area. qualitativeb. quantitativec. either qualitative or quantitatived. neither qualitative nor quantitativeANS: A PTS: 1 TOP: Descriptive Statistics30. Arithmetic operations are inappropriate fora. qualitative datab. quantitative datac. both qualitative and quantitative datad. large data setsANS: A PTS: 1 TOP: Descriptive Statistics31. Income is an example ofa. qualitative datab. either qualitative or quantitative datac. dollar datad. quantitative dataANS: D PTS: 1 TOP: Descriptive Statistics32. Data collected at the same, or approximately the same, point in time area. time series datab. approximate time series datac. crossectional datad. approximate dataANS: C PTS: 1 TOP: Descriptive Statistics33. Data collected over several time periods area. time series datab. time controlled datac. crossectional datad. time crossectional dataANS: A PTS: 1 TOP: Descriptive Statistics34. Statistical studies in which researchers do not control variables of interest area. experimental studiesb. uncontrolled experimental studiesc. not of any valued. observational studiesANS: D PTS: 1 TOP: Descriptive Statistics35. Statistical studies in which researchers control variables of interest area. experimental studiesb. control observational studiesc. non-experimental studiesd. observational studiesANS: A PTS: 1 TOP: Descriptive Statistics36. The summaries of data, which may be tabular, graphical, or numerical, are referred to asa. inferential statisticsb. descriptive statisticsc. statistical inferenced. report generationANS: B PTS: 1 TOP: Descriptive Statistics37. Statistical inferencea. refers to the process of drawing inferences about the sample based on the characteristics ofthe populationb. is the same as descriptive statisticsc. is the process of drawing inferences about the population based on the information takenfrom the sampled. is the same as a censusANS: C PTS: 1 TOP: Descriptive Statistics38. The collection of all elements of interest in a particular study isa. the populationb. the samplingc. statistical inferenced. descriptive statisticsANS: A PTS: 1 TOP: Descriptive Statistics39. A portion of the population selected to represent the population is calleda. statistical inferenceb. descriptive statisticsc. a censusd. a sampleANS: D PTS: 1 TOP: Statistical Inference40. In a sample of 800 students in a university, 240, or 30%, are Business majors. The 30% is an example ofa. a sampleb. a populationc. statistical inferenced. descriptive statisticsANS: D PTS: 1 TOP: Descriptive Statistics41.In a sample of 400 students in a university, 80, or 20%, are Business majors. Based on the aboveinformation, the school's paper reported that "20% of all the students at the university are Business majors." This report is an example ofa. a sampleb. a populationc. statistical inferenced. descriptive statisticsANS: C PTS: 1 TOP: Descriptive Statistics42. Five hundred residents of a city are polled to obtain information on voting intentions in an upcoming cityelection. The five hundred residents in this study is an example of a(n)a. censusb. samplec. observationd. populationANS: B PTS: 1 TOP: Descriptive Statistics43. A statistics professor asked students in a class their ages. On the basis of this information, the professorstates that the average age of all the students in the university is 24 years. This is an example ofa. a censusb. descriptive statisticsc. an experimentd. statistical inferenceANS: D PTS: 1 TOP: Statistical Inference44. The owner of a factory regularly requests a graphical summary of all employees' salaries. The graphicalsummary of salaries is an example ofa. a sampleb. descriptive statisticsc. statistical inferenced. an experimentANS: B PTS: 1 TOP: Descriptive Statistics45. The Department of Transportation of a city has noted that on the average there are 17 accidents per day.The average number of accidents is an example ofa. descriptive statisticsb. statistical inferencec. a sampled. a populationANS: A PTS: 1 TOP: Statistical Inference46. The process of analyzing sample data in order to draw conclusions about the characteristics of apopulation is calleda. descriptive statisticsb. statistical inferencec. data analysisd. data summarizationANS: B PTS: 1 TOP: Descriptive Statistics47. In a post office, the mailboxes are numbered from 1 to 4,500. These numbers representa. qualitative datab. quantitative datac. either qualitative or quantitative datad. since the numbers are sequential, the data is quantitativeANS: A PTS: 1 TOP: Descriptive Statistics48. The average age in a sample of 190 students at City College is 22. As a result of this sample, it can beconcluded that the average age of all the students at City Collegea. must be more than 22, since the population is always larger than the sampleb. must be less than 22, since the sample is only a part of the populationc. could not be 22d. could be larger, smaller, or equal to 22ANS: D PTS: 1 TOP: Descriptive Statistics49.Since a sample is a subset of the population, the sample meana. is always smaller than the mean of the populationb. is always larger than the mean of the populationc. must be equal to the mean of the populationd. can be larger, smaller, or equal to the mean of the populationANS: D PTS: 1 TOP: Descriptive Statistics50. The scale of measurement that is simply a label for the purpose of identifying the attribute of an elementis thea. ratio scaleb. nominal scalec. ordinal scaled. interval scaleANS: B PTS: 1 TOP: Descriptive Statistics51. In a data set, the number of elements will always be the same as the number ofa. independent variablesb. observationsc. data pointsd. dependent variablesANS: B PTS: 1 TOP: Descriptive Statistics52. Which of the following is not a scale of measurement?a. nominalb. ordinalc. intervald. primalANS: D PTS: 1 TOP: Descriptive Statistics53. Which of the following is a scale of measurement?a. ratiob. primalc. divisionald. remedialANS: A PTS: 1 TOP: Descriptive Statistics54. Which scale of measurement can be either numeric or nonnumeric?a. nominalb. ratioc. intervald. None of these alternatives is correct.ANS: A PTS: 1 TOP: Descriptive Statistics55. Which of the following variables use the ratio scale of measurement?a. social security numberb. temperaturec. genderd. incomeANS: D PTS: 1 TOP: Descriptive Statistics56. The weight of a candy bar in ounces is an example ofa. qualitative datab. either qualitative or quantitative datac. weight datad. quantitative dataANS: D PTS: 1 TOP: Descriptive Statistics57. The height of a building, measured in feet, is an example ofa. qualitative datab. either qualitative or quantitative datac. feet datad. quantitative dataANS: D PTS: 1 TOP: Descriptive Statistics58. An interviewer has made an error in recording the data. This type of error is known asa. an experimental errorb. a data acquisition errorc. a non-experimental errord. a conglomerate errorANS: B PTS: 1 TOP: Descriptive Statistics59. Census refers toa. an experimental study to collect data on the entire populationb. an experimental study to collect data on a samplec. a survey to collect data on a sampled. a survey to collect data on the entire populationANS: D PTS: 1 TOP: Descriptive Statistics60. In experimental studies, the variable of interesta. is not controlledb. is controlledc. must be numericald. cannot be numericalANS: B PTS: 1 TOP: Descriptive Statistics61. In observational studies, the variable of interesta. is not controlledb. is controlledc. must be numericald. cannot be numericalANS: A PTS: 1 TOP: Descriptive Statistics62. How many scales of measurement exist?a. 1b. 2c. 3d. 4ANS: D PTS: 1 TOP: Descriptive Statistics63. Which of the following can be classified as quantitative data?a. interval and ordinalb. ratio and ordinalc. nominal and ordinald. interval and ratioANS: D PTS: 1 TOP: Descriptive Statistics64. The sample sizea. can be larger than the population sizeb. is always smaller than the population sizec. can be larger or smaller than the population sized. is always equal to the size of the populationANS: B PTS: 1 TOP: Descriptive Statistics65. A population isa. the same as a sampleb. the selection of a random samplec. the collection of all items of interest in a particular studyd. always the same size as the sampleANS: C PTS: 1 TOP: Descriptive Statistics66. In a random sample of 200 items, 5 items were defective. An estimate of the percentage of defectiveitems in the population isa. 5.0%b. 2.5%c. 200d. 10.0%ANS: B PTS: 1 TOP: Descriptive Statistics67. On a street, the houses are numbered from 300 to 450. The house numbers are examples ofa. qualitative datab. quantitative datac. both quantitative and qualitative datad. neither quantitative nor qualitative dataANS: A PTS: 1 TOP: Descriptive Statistics68. A survey to collect data on the entire population isa. a censusb. a samplec. a populationd. an inferenceANS: A PTS: 1 TOP: Descriptive Statistics69. In Excel, a worksheet that displays the data for the problem and shows the results of the analysis isa. a formula worksheetb. a value worksheetc. an absolute worksheetd. a descriptive worksheetANS: B PTS: 1 TOP: Descriptive Statistics70. In Excel, a worksheet that displays the formulas used to create the results is aa. results worksheetb. formula worksheetc. value worksheetd. sample worksheetANS: B PTS: 1 TOP: Descriptive StatisticsNARRBEGIN: Exhibit 1-1Exhibit 1-1In a recent study based upon an inspection of 200 homes in Daisy City, 80 were found to violate one or more city codes.NARREND71. Refer to Exhibit 1-1. The city manager released a statement that 40% of Daisy City's 2,000 homes are inviolation of city codes. The manager's statement is an example ofa. a censusb. an experimentc. descriptive statisticsd. statistical inferenceANS: D PTS: 1 TOP: Descriptive StatisticsNAR: Exhibit 1-172. Refer to Exhibit 1-1. The Daisy City study described above is an example of the use of aa. censusb. samplec. probabilityd. populationANS: B PTS: 1 TOP: Descriptive StatisticsNAR: Exhibit 1-173. Refer to Exhibit 1-1. The manager's statement that 40% of Daisy City's 2,000 homes are in violation ofcity codes isa. an exactly correct statementb. only an approximation, since it is based upon sample informationc. obviously wrong, since it is based upon a study of only 200 homesd. None of these alternatives is correct.ANS: B PTS: 1 TOP: Descriptive StatisticsNAR: Exhibit 1-1NARRBEGIN: Exhibit 1-2Exhibit 1-2In a sample of 1,600 registered voters, 912, or 57%, approve of the way the President is doing his job.NARREND74. Refer to Exhibit 1-2. The 57% approval is an example ofa. a sampleb. descriptive statisticsc. statistical inferenced. a populationANS: B PTS: 1 TOP: Descriptive StatisticsNAR: Exhibit 1-275. Refer to Exhibit 1-2. A political pollster states: "Fifty-seven percent of all voters approve of thePresident." This statement is an example ofa. a sampleb. descriptive statisticsc. statistical inferenced. a populationANS: C PTS: 1 TOP: Descriptive StatisticsNAR: Exhibit 1-2NARRBEGIN: Exhibit 1-3Exhibit 1-3Part of the data bank of a corporation is shown below.EmployeeNumber Gender DepartmentYears ofExperienceEmployee Rank(1 - 10)YearlySalary23450 Male Accounting 15 10 $ 52,443.00 34568 Female IT 24 7 $111,239.00 23123 Female Personnel 20 4 $ 84,473.00 23007 Male Finance 9 1 $ 47,519.00NARREND76. Refer to Exhibit 1-3. Employee Number is an example of ________ data.a. nominalb. ordinalc. intervald. ratioANS: A PTS: 1 TOP: Descriptive StatisticsNAR: Exhibit 1-377. Refer to Exhibit 1-3. Gender is an example of ________ data.a. nominalb. ordinalc. intervald. ratioANS: A PTS: 1 TOP: Descriptive StatisticsNAR: Exhibit 1-378. Refer to Exhibit 1-3. Years of Experience is an example of ________ data.a. nominalb. ordinalc. intervald. ratioANS: D PTS: 1 TOP: Descriptive StatisticsNAR: Exhibit 1-379. Refer to Exhibit 1-3. Employee Rank is an example of ________ data.a. nominalb. ordinalc. intervald. ratioANS: B PTS: 1 TOP: Descriptive StatisticsNAR: Exhibit 1-380. Refer to Exhibit 1-3. Yearly Salary is an example of ________ data.a. nominalb. ordinalc. intervald. ratioANS: D PTS: 1 TOP: Descriptive StatisticsNAR: Exhibit 1-3NARRBEGIN: Exhibit 1-4Exhibit 1-4In many universities, students evaluate their professors by means of answering a questionnaire. Assumea questionnaire is distributed to a class of 45 students. Students are asked to answer the following:1. Sex2. Race (Black, White, Other)3. Age4. Number of hours completed5. Grade point average6. My instructor is a very effective teacher1 2 3 4 5strongly agree moderately agree neutral moderately disagree strongly disagree NARREND81. Refer to Exhibit 1-4. How many elements are in the above data set?a. 5b. 6c. 3d. 45ANS: D PTS: 1 TOP: Descriptive StatisticsNAR: Exhibit 1-482. Refer to Exhibit 1-4. How many variables are in this data set?a. 3b. 4c. 5d. 6ANS: D PTS: 1 TOP: Descriptive StatisticsNAR: Exhibit 1-483. Refer to Exhibit 4-1. How many observations are in this data set?a. 5b. 6c. 3d. 45ANS: D PTS: 1 TOP: Descriptive StatisticsNAR: Exhibit 1-4PROBLEM1. After graduation ceremonies at a university, six graduates were asked whether they were in favor of(identified by 1) or against (identified by 0) abortion. Some information about these graduates is shown below.Graduate Sex Age Abortion Issue Class RankMarissa F 24 1 1Jason M 22 1 2Wendy F 41 0 3Edward M 38 0 20Jennifer F 25 1 4Tim M 19 0 8a. How many elements are in the data set?b. How many variables are in the data set?c. How many observations are in the data set?d. Which of the above variables (Sex, Age, Abortion Issue, Class rank) are qualitative and whichare quantitative variables?e. Are arithmetic operations appropriate for the variable "abortion issue"?ANS:a. 6b. 4c. 6d. Sex: qualitativeAge: quantitativeAbortion Issue: qualitativeClass Rank: qualitativee. NoPTS: 1 TOP: Descriptive Statistics2. A recent issue of Fortune Magazine reported that the following companies had the lowest sales peremployee among the Fortune 500 companies.Sales per Employee (In $1,000s) Sales RankCompanySeagate Technology 42.20 285SSMC 42.19 414Russel 41.99 480Maxxam 40.88 485Dibrell Brothers 22.56 470a. How many elements are in the above data set?b. How many variables are in the above data set?c. How many observations are in the above data set?d. Name the variables and indicate whether they are qualitative or quantitative.ANS:a. 5b. 2c. 5d. Sales per employee: quantitative; Sales rank: qualitativePTS: 1 TOP: Descriptive Statistics3. The following shows the temperatures (high, low) and weather conditions in a given Sunday for someselected world cities. For the weather conditions, the following notations are used: c = clear; cl = cloudy;sh = showers; pc = partly cloudy.City Hi Lo ConditionAcapulco 99 77 pcBangkok 92 78 pcMexico City 77 57 shMontreal 72 56 pcParis 77 58 cRome 88 68 clToronto 78 61 ca. How many elements are in this data set?b. How many variables are in this data set?c. How many observations are in this data set?d. Name the variables and indicate whether they are qualitative or quantitative.e. For which variables are arithmetic operations appropriate and for which are they notappropriate?ANS:a. 7b. 3c. 7d. Hi: quantitative, Lo: quantitative, Condition: qualitativee. Hi: appropriate, Lo: appropriate, Condition: not appropriatePTS: 1 TOP: Descriptive Statistics4. The following data shows the yearly income distribution of a sample of 200 employees at MNM, Inc.Yearly Income (In $1,000s)Number of Employees20 - 24 225 - 29 4830 - 34 6035 - 39 8040 - 44 10a. What percentage of employees has yearly incomes of $35,000 or more?b. Is the figure (percentage) that you computed in Part a an example of statistical inference? If no,what kind of statistics does it represent?c. Based on this sample, the president of the company said that "45% of all our employees' yearlyincomes are $35,000 or more." The president's statement represents what kind of statistics?d. With the statement made in Part c, can we be assured that more than 45% of all employees'yearly incomes are at least $35,000? Explain.e. What percentage of employees of the sample has yearly incomes of $29,000 or less?f. How many variables are presented in the above data set?g. The above data set represents the results of how many observations?ANS:a. 45%b. No, it is descriptive statistics.c. statistical inferenced. No, this is simply an inference and approximation based on the sample information.e. 25%f. 2g. 200PTS: 1 TOP: Descriptive Statistics5. A recent issue of a national magazine reported that in a national public opinion survey conducted among2,000 individuals, 56% were in favor of gun control, 40% opposed gun control, and 4% had no opinion on the subject.a. What is the sample in this survey?b. Based on the sample, what percentage of the population would you think is in favor of gun control?c. Based on the sample, what percentage of the population would you think have no opinion on thesubject?ANS:a. The 2000 individuals who were approachedb. 56%c. 4%PTS: 1 TOP: Descriptive Statistics6. The following table shows the starting salaries of a sample of recent business graduates.Income (In $1,000s) Number of Graduates15 - 19 4020 - 24 6025 - 29 8030 - 34 1835 - 39 2a. What percentage of graduates in the sample had starting salaries of at least $30,000?b. Of the graduates in the sample, what percentage had starting salaries of less than $25,000?c. Based on this sample, what percentage of all business graduates do you estimate to have startingsalaries of at least $20,000?ANS:a. 10%b. 50%c. 80%PTS: 1 TOP: Descriptive Statistics7. Michael, Inc., a manufacturer of electric guitars, is a small firm with 50 employees. The table belowshows the hourly wage distribution of the employees.Hourly Wages (In Dollars) Number of Employees10 - 13 814 - 17 1218 - 21 2022 - 25 10a. How many employees receive hourly wages of at least $18?b. What percentage of the employees has hourly wages of at least $18?c. What percentage of the employees has hourly wages of less than $14?ANS:a. 30b. 60%c. 16%PTS: 1 TOP: Descriptive Statistics8. The following information regarding the top eight Fortune 500 companies was presented in an issue ofFortune Magazine.Sales $ Millions SalesRankProfits$ MillionsProfitsRankCompanyGeneral Motors 161,315 1 2,956 30 Ford Motor 144,416 2 22,071 2 Wal-Mart Stores 139,208 3 4,430 14 Exxon 100,697 4 6,370 5 General Electric 100,469 5 9,269 3 Int'l Business Machines 81,667 6 6,328 6 Citigroup 76,431 7 5,807 8 Philip Morris 57,813 8 5,372 9 Boeing 56,154 9 1,120 82 AT&T 53,588 10 6,398 4a. How many elements are in the above data set?b. How many variables are in this data set?c. How many observations are in this data set?d. Which variables are qualitative and which are quantitative variables?e. What measurement scale is used for each variable?ANS:a. 10b. 4c. 10d. Sales and Profits are quantitativeSales Rank, and Profits Rank are qualitativee. Sales: ratioSales Rank: ordinalProfits: ratioProfits Rank: ordinalPTS: 1 TOP: Descriptive Statistics9. The following information regarding a sample of seven students is provided.Student Identificationnumber Grade PointAverageClassification Gender Rank inClassAdam 1234 2.89 Senior Male 15 Brandon 8978 2.01 Junior Male 25 Jason 6578 3.97 Freshman Male 3 Marissa 2345 3.98 Sophomore Female 2 Michelle 8901 2.67 Senior Female 18 Wendy 7789 4.00 Senior Female 1 Webster 6780 3.77 Freshman Male 4a. How many elements are in the above data set?b. How many variables are in this data set?c. How many observations are in this data set?d. Which variables are qualitative and which are quantitative variables?e. What measurement scale is used for each variable?。

商务统计试题及答案

商务统计试题及答案一、选择题（每题2分，共20分）1. 商务统计的主要目的是：A. 收集数据B. 分析数据C. 做出决策D. 预测未来2. 下列哪项不是描述性统计的内容？A. 均值B. 方差C. 相关性D. 抽样3. 正态分布的特点是：A. 所有数据都集中在中间B. 大部分数据分布在两端C. 数据分布是对称的D. 数据分布是不规则的4. 在商务统计中，相关系数的取值范围是：A. -1 到 1B. 0 到 1C. -∞ 到+∞D. 1 到 105. 以下哪个是假设检验的步骤？A. 确定显著性水平B. 收集数据C. 计算样本均值D. 所有选项都是二、简答题（每题10分，共30分）6. 简述商务统计中的抽样误差和非抽样误差的区别。

7. 解释什么是置信区间，并举例说明其在商务决策中的应用。

8. 描述回归分析在商务决策中的作用。

三、计算题（每题25分，共50分）9. 假设你是一家零售公司的分析师，你收集了以下数据，显示了过去10天的日销售额（单位：千元）：120, 130, 110, 140, 150, 160, 170, 180, 190, 200。

请计算：- 均值- 中位数- 方差- 标准差10. 假设你正在分析两个变量X和Y之间的关系，收集到以下数据点（X, Y）：(1, 2), (2, 3), (3, 5), (4, 7), (5, 9)。

请计算：- 线性回归方程- 相关系数- 预测当X=6时的Y值答案一、选择题1. C. 做出决策2. D. 抽样3. C. 数据分布是对称的4. A. -1 到 15. D. 所有选项都是二、简答题6. 抽样误差是由于从总体中抽取的样本不能完全代表总体而产生的误差。

非抽样误差可能由数据收集、处理或分析过程中的错误引起，与抽样过程无关。

7. 置信区间是指在一定置信水平下，总体参数可能取值的范围。

例如，在市场研究中，置信区间可以用来估计某个新产品的潜在市场份额。

8. 回归分析可以帮助预测一个变量（因变量）如何依赖于一个或多个其他变量（自变量）。

商务统计大题

P821.某车间100名工人日产零件数资料如表3.1所示：表3.1某车间100名工人日产零件数资料日产零件数/件工人数/人 65 10 70 25 75 40 80 18 85 7 合计 100 要求：计算该车间工人的平均日产零件数。

∑∑=fxf X 7184025107851880407525701065++++⨯+⨯+⨯+⨯+⨯=743574.35/100==（件人）2.某公司8月份职工工资资料如表3.2所示：工资/元人数比重/% 1600以下 101600-1800 25 1800-2000 35 2000-2200 20 2400以上 10 合计 100要求：计算该企业职工平均工资。

解：依题意得各组组中值为：1500,1700,1900,2100,2500（元/人）3.已知某企业某同类产品3种不同型号的有关资料如表3.3所示：表3.3某企业某同类产品3种不同型号的有关资料产品单位成本/（元/件-1） 2007年产量/件 2008年成本总额/元甲 25 1500 24500 乙 28 1020 28560 丙 32 980 48000 合计 --- 3500 101060 要求：分别计算企业该产品2007年，2008年的平均单位产品成本。

2007年：件）元/(83.273500974209801020150098032102028150025==++⨯+⨯+⨯=∑∑=-f xf x2008年：件）（元/87.28350001010603248000282856002524500480002856024500==++++=∑∑=-x m m x4. 对某鱼塘的鱼进行抽样调查。

从鱼塘的不同部位同时撒网捕到鱼150条，其中草鱼123条，草鱼平均每条重2千克，标准差0.75千克。

试按99.73%的保证程度(t=3)：(1) )对该鱼塘草鱼所占比重作区间估计。

(2)对该鱼塘草鱼平均每条重量作区间估计；解：（1）依题意得t=3 n=150 s=0.75（2）P13913.某保险公司自投保人中随机抽取36人，计算出此36人的平均年龄为39.5岁，已经投保人年龄分布近似正态分布，标准差为7.2岁，试求所有投保人平均年龄99%的置信区间解：已知，X ～N （μ，7.22），岁，n ＝36，1－α＝0.99，则当α＝0.01，有U α / 2 = U 0.01 / 2 = U 0.005 = 2.575，所以，即总体的置信区间为[36.41，42.59]。

商务统计试题-精选版

《商务统计》试题选登一、单项选择题下列各题A）、B） C）、D）四个选项中，只有一个选项是正确的。

1．进行全国人口普查，普查总体中的个体是A）每个省的人口B）每个县的人口C）每个家庭的人口D）每个人2．根据人的性别特征将人口划分为男性和女性两类，所采用的测度计量尺度是A）名义尺度B）顺序尺度C）差距尺度D）比例尺度3．某市场调查公司为了对一家大型商场做顾客满意度调查，对不同性别和年龄的顾客按事先规定的人数随意进行了一些调查询问，这种调查属于A）任意调查B）立意调查C）配额抽样D）整群抽样4．利用拉丁方来安排试验观测，所需要考虑的因素只能为A）2个B）3个C）4个D）5个5.从0-1分布总体中进行不放回抽样，样本中具有1值的个体数服从A）两点分布B）二项分布C）超几何分布D）泊松分布6.测度随机变量分布中心最常用的指标是A）算术平均数B）中位数C）众数D）调和平均数7.变量x与y的相关系数的符号取决于A）变量x的标准差B）变最y的标准差C）变量x和y两标准差的乘积D）变量x和y的协方差8.有一个样本容量为10的样本，其均值为1300小时，方差为8175.56。

若按放回抽样计算，则样本均值的标准误是A）28.35 小时B）28.59 小时C）29.61 小时D）30.02 小时9.在关于总体参数的假设检验中，原假设必须是一个A）精确假设B）非精确假设C）复合假设D）备择假设10.如果原假设为H0：eze0,备则假设为乩.。

＜。

0,则进行假设检验时应采用A）侧检验B）左侧检验0双侧检验D）上侧检验11.在方差分析中，各次试验观测应A）相互关联B）互不相关C）计量逐步精确D）方法逐步改进12.相关关系是变量之间一种A）线性函数依存关系B）确定性的数量依存关系C）非线性函数依存关系D）非确定性的数量依存关系13.对于回归模型刀=九+8信+邛］=1,2,…，口），为了进行统计推断，通常假定'、u2、…、u n的数学期望J 。

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Practice Test 1 Business Statistics:Multiple Choice: Each is worth two pointsIdentify the letter of the choice that best completes the statement or answers the question. **Skip 15-17,18,20 Ch10-12,13 Material____ 1. The sum of the relative frequencies for all classes will always equal a.the sample sizeb.the number of classesc.oned.any value larger than one____ 2. The interquartile range isa.the 50th percentileb.another name for the variancec . the difference between the largest and smallest valuesd . the difference between the third quartile and the first quartile____ 3. The standard deviation of a sample of 100 observations equals 64. The variance of the sample equalsa.8b.10c.6400d.4,096____ 4. The numerical value of the standard deviation can never bea.larger than the variance.cnegative.smaller than the varianced.____ 5. The set of all possible sample points (experimental outcomes) is called aa sample.an eventb.cthe sample space.a populationd.____ 6. A random variable that can assume only a finite number of values is referred to as a(n)infinite sequencea.bfinite sequence.discrete random variablec.discrete probability functiond.Exhibit 5-11A local bottling company has determined the number of machine breakdowns permonth and their respective probabilities as shown below:Number ofBreakdowns Probability0 0.121 0.382 0.253 0.184 0.07____ 7. Refer to Exhibit 5-11. The probability of at least 3 breakdowns in a month is a0.5b0.10.c0.30.d0.90.____ 8. A normal probability distributionis a continuous probability distributiona.bis a discrete probability distribution.can be either continuous or discretec.dmust have a standard deviation of 1.Exhibit 6-6The starting salaries of individuals with an MBA degree are normally distributedwith a mean of $40,000 and a standard deviation of $5,000.____ 9. Refer to Exhibit 6-6. What percentage of MBA's will have starting salaries of $34,000 to $46,000?a38.49%.38.59%b.50%c.76.98%d.____10. Given that Z is a standard normal random variable, what is the value of Z if the area between -Z and Z is 0.901?1.96a.-1.96b.0.4505c.d 1.65____11. Which of the following is not a measure of central location?amean.medianb.variancec.moded.____12. The descriptive measure of dispersion that is based on the concept of a deviation about the mean isthe rangea.the interquartile rangeb.the absolute value of the rangec.the standard deviationd.____13. Which of the following symbols represents the mean of the population?aσ2.bσ.cμ.d.____14. Which of the following symbols represents the size of the sampleaσ2.bσ.Nc.d n____15. If two events are independent, thenathey must be mutually exclusive.the sum of their probabilities must be equal to oneb.ctheir intersection must be zero.None of these alternatives is correct..d.____16. Which of the following statements is(are) always true?a-1 ≤ P(E i) ≤1.P(A) = 1 - P(A c)b.P(A) + P(B) = 1c.d∑P ≥ 1.____17. A measure of the average value of a random variable is called a(n)variancea.bstandard deviation.expected valuec.coefficient of variationd.____18. Four percent of the customers of a mortgage company default on their payments. A sample of five customers is selected. What is the probability that exactly twocustomers in the sample will default on their payments?0.2592a.0.0142b..0.7408d.____19. The expected value of a discrete random variablea. is the most likely or highest probability value for the randomvariableb. will always be one of the values x can take on, although it maynot be the highest probability value for the random variablec. is the average value for the random variable over many repeats ofthe experimentd. None of these alternatives is correct.____20. Which of the following is not a property of a binomial experiment?a. the experiment consists of a sequence of n identical trialsb. each outcome can be referred to as a success or a failurec. the probabilities of the two outcomes can change from onetrial to the nextd. the trials are independentExhibit 5-9The probability distribution for the daily sales at Michael's Co. is given below.Daily Sales(In $1,000s) Probability40 0.150 0.460 0.370 0.2____21. Refer to Exhibit 5-9. The expected daily sales are$55,000a.$56,000b.$50,000c.$70,000d.azero.-0.5b.c0.5.oned.Exhibit 6-2The weight of football players is normally distributed with a mean of 200 poundsand a standard deviation of 25 pounds.____23. Refer to Exhibit 6-2. What percent of players weigh between 180 and 220 pounds?a. 28.81%b0.5762%.c. 0.281%57.62%d.Exhibit 6-6The starting salaries of individuals with an MBA degree are normally distributedwith a mean of $40,000 and a standard deviation of $5,000.____24. Refer to Exhibit 6-6. What is the probability that a randomly selected individual with an MBA degree will get a starting salary of at least $47,500?a. 0.4332b. 0.9332c. 0.0668d. 0.5000Short Answer/Problems1.The following data represent the daily demand (y in thousands of units) and the unit price (xin dollars) for a product.Daily Demand (y) Unit Price (x)47 139 335 544 334 620 815 16a. Compute and interpret the sample covariance for the above data.b. Compute and interpret the sample correlation coefficient.2.The daily dinner bills in a local restaurant are normally distributed with a mean of $28 and astandard deviation of $6.a. What is the probability that a randomly selected bill will be at least $39.10?b. What percentage of the bills will be less than $16.90?c. What are the minimum and maximum of the middle 95% of the bills?d. If twelve of one day's bills had a value of at least $43.06, how many bills didthe restaurant collect on that day?3.Below you are given a partial computer output based on a sample of 7 observations, relatingan independent variable (x) and a dependent variable (y).Predictor Coefficient StandardErrorConstant 24.112 8.376x -0.252 0.253Analysis of VarianceSOURCE SSRegression 196.893Error 94.822a. Develop the estimated regression line.b. If you are given that x = 50, find the estimate of y based on your regressionequation.c. Determine the coefficient of determination and interpret your answer. Solutions to MC1. C2. D3. D4. C5. C6. C7. D8. A9. D 10. D11. C 12. D 13. C 14. D 15. D 16. B 17. C 18. B19. C 20. C 21. B 22. C 23. D 24. C 25. C 26. A27. B 28. D 29. CSolutions to Short Answer1. ANS:a. -47 (rounded). Since the covariance is negative, it indicates a negativerelationship between x and y.b. -0.922. There is a strong negative relationship between x and y.2. ANS:a. 0.0322b. 0.0322d. 2,0003. ANS:a. = 24.112 + 0.816xb. If x = 50 then = 24.112 + 0.816x 24.1 + 0.82 ( 50 ) = 65.1c. 0.675 So there is a fairly strong positive relationship between x and y.Practice Test 2 Business Statistics:Multiple Choice: Each is worth two pointsIdentify the letter of the choice that best completes the statement or answers the question.____ 1. The sample statistic s is the point estimator ofa. μbσ.c.d.____ 2. A sample statistic is an unbiased estimator of the population parameter ifa. the expected value of the sample statistic is equal to zerob. the expected value of the sample statistic is equal to onec. the expected value of the sample statistic is equal to thepopulation parameterd. it is equal to zero____ 3. A property of a point estimator that occurs whenever larger sample sizes tend to provide point estimates closer to the population parameter is known asa. efficiencyb. unbiased samplingc. consistencyd. relative estimation____ 4. A random sample of 121 bottles of cologne showed an average content of 4 ounces.It is known that the standard deviation of the contents (i.e., of the population) is 0.22ounces. In this problem the 0.22 isa. a parameterb. a statisticd. the average content of colognes in the long run____ 5. A sample of 92 observations is taken from an infinite population. The sampling distribution of is approximatelya. normal because is always approximately normally distributedb. normal because the sample size is small in comparison to thepopulation sizec. normal because of the central limit theoremd. None of these alternatives is correct.____ 6. As the number of degrees of freedom for a t distribution increases, the difference between the t distribution and the standard normal distributiona. becomes largerb. becomes smallerc. stays the samed. None of these alternatives is correct.____ 7. From a population of 200 elements, a sample of 49 elements is selected. It is determined that the sample mean is 56 and the sample standard deviation is 14. Thestandard error of the mean isa. 3b. 2c. greater than 2d. less than 2____ 8. Which of the following is(are) point estimator(s)?a. σb. μc. sd. α____ 9. A population characteristic, such as a population mean, is calleda. a statistica parameterb.c. a sampledthe mean deviation.____10. The sample statistic, such as , s, or , that provides the point estimate of the population parameter is known asa. a point estimatorb. a parameterc. a population parameterd. a population statistic____11. The fact that the sampling distribution of sample means can be approximated by a normal probability distribution whenever the sample size is large is based on thea. central limit theoremb. fact that we have tables of areas for the normal distributionc. assumption that the population has a normal distributiond. None of these alternatives is correct.____12. Random samples of size 17 are taken from a population that has 200 elements, a mean of 36, and a standard deviation of 8. The mean and the standard deviation ofthe sampling distribution of the sample means area. 8.7 and 1.94b. 36 and 1.94c. 36 and 1.86d. 36 and 8____13. When constructing a confidence interval for the population mean and a small sample is used, the degrees of freedom for the t distribution equalsa. n-1b. nc. 29d. 30_____ 14. The collection of all possible sample points in an experiment isa. the sample spaceb. a sample pointc.an experimentd. the population_____ 15. Of five letters (A, B, C, D, and E), two letters are to be selected at random. How many possible selections are there?a. 20b. 7c. 5!d. 10_____ 16. The “Top Three” at a racetrack consists of picking the correct order of the first three horses in a race. If there are 10 horses in a particular race, how many “Top Three”outcomes are there?a. 302,400b. 720c. 1,814,400d. 10_____ 17. Given that event E has a probability of 0.25, the probability of the complement of event Ea. cannot be determined with the above informationb. can have any value between zero and onec. must be 0.75d. is 0.25_____ 18. The symbol ⋃ shows thea.union of eventsb. intersection of eventsc.sum of the probabilities of eventsd.sample space_____ 19. If P(A) = 0.38, P(B) = 0.83, and P(A ⋂ B) = 0.57; then P(A ⋃ B) =a. 1.21b. 0.64c. 0.78d. 1.78_____ 20. If P(A) = 0.62, P(B) = 0.47, and P(A ⋃ B) = 0.88; then P(A ⋂ B) =a. 0.2914b. 1.9700c. 0.6700d.0.2100_____ 21. If P(A) = 0.85, P(A ⋃ B) = 0.72, and P(A ⋂ B) = 0.66, then P(B) =a. 0.15b. 0.53c. 0.28d. 0.15_____ 22. Two events are mutually exclusive ifa. the probability of their intersection is 1b. they have no sample points in commonc. the probability of their intersection is 0.5d. the probability of their intersection is 1 and they have no sample points in common_____ 23. If A and B are mutually exclusive events with P(A) = 0.3 and P(B) = 0.5, then P(A ⋂ B) =a. 0.30b. 0.15c. 0.00d. 0.20_____ 24. If A and B are mutually exclusive events with P(A) = 0.3 and P(B) = 0.5, then P(A ⋃ B) =a. 0.00b. 0.15c. 0.8d. 0.2_____ 25. A subset of a population selected to represent the population is aa.subsetb.samplec.small populationd. None of the alternative answers is correct._____ 26. A simple random sample of size n from an infinite population of size N is to be selected. Each possible sample should havea. the same probability of being selectedb. a probability of 1/n of being selectedc. a probability of 1/N of being selectedd. a probability of N/n of being selected_____ 27. A probability distribution for all possible values of a sample statistic is known as aa.sample statisticb.parameterc.simple random sampled.sampling distribution_____ 28. From a population of 200 elements, the standard deviation is known to be 14.A sample of 49 elements is selected. It is determined that the sample mean is 56. The standard error of the mean isa. 3b. 2c. greater than 2d. less than 2_____ 29. From a population of 500 elements, a sample of 225 elements is selected. It is known that the variance of the population is 900. The standard error of the mean is approximatelya. 1.1022b. 2c. 30d. 1.4847Short Answer/ProblemsDirections: Clearly designate your solution to each portion of the questions asked and show your entire work and method for arriving at the solution.1. The sales records of a real estate agency show the following sales over the past 200 days:b. Assign probabilities to the sample points and show their values.c. What is the probability that the agency will not sell any houses in a given day?d. What is the probability of selling at least 2 houses?e. What is the probability of selling 1 or 2 houses?f. What is the probability of selling less than 3 houses?2. Assume two events A and B are mutually exclusive and, furthermore, P(A) = 0.2 and P(B)= 0.4.a. Find P(A ⋂ B).b. Find P(A ⋃ B).c. Find P(A⎜B).3.You are given the following information on Events A, B, C, and D. P(A) = .4, P(B) = .2,P(C) = .1,P(A ⋃ D) = .6, P(A⎜B) = .3, P(A ⋂ C) = .04, P(A ⋂ D) = .03a. Compute P(D).b. Compute P(A ⋂ B).c. Compute P(A⎜C).d. Compute the probability of the complement of C.e. Are A and B mutually exclusive? Explain your answer.f. Are A and B independent? Explain your answer.g. Are A and C mutually exclusive? Explain your answer.h. Are A and C independent? Explain your answer.4. Consider a population of five weights identical in appearance but weighing 1, 3, 5, 7, and 9 ounces.a. Determine the mean and the variance of the population.b. Sampling without replacement from the above population with a sample sizeof 2 produces ten possible samples. Using the ten sample mean values, determinethe mean of the population and the variance of .c. Compute the standard error of the mean.5. A population of 1,000 students spends an average of $10.50 a day on dinner. The standard deviation of the expenditure is $3. A simple random sample of 64 students is taken.a. What are the expected value, standard deviation, and shape of the samplingdistribution of the sample mean?b. What is the probability that these 64 students will spend a combined total of morethan $715.21?c. What is the probability that these 64 students will spend a combined total between$703.59 and $728.45?Solutions to MC Problems1. B 2 C 3. C 4. A 5. C 6. B 7. D 8. C 9. B 10. A11. A 12. C 13. A 14. A 15. D 16. B 17. C 18. A19. B 20. D 21. B 22. B 23. C 24. C 25. B 26. A27. D 28. D 29. DShort Answer/ProblemsDirections: Clearly designate your solution to each portion of the questions asked and show your entire work and method for arriving at the solution.1. ANSWERS:2. ANSWERS:a. 0.0 b. 0.6 c. 0.03ANSWERS:a. 0.23b. 0.06c. 0.4d. 0.9e. No, P(A⎜B) ≠ 0f. No, P(A⎜B) ≠ P(A)g. No, P(A ⋂ C) ≠ 0h. Yes, P(A⎜C) = P(A)4. ANSWERS:a. 5 and 8b. 5 and 3c. 1.7325. ANSWERS:a. 10.5 0.363 normalb. 0.0314c. 0.0794。

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