生物统计学(第3版)杜荣骞课后习题答案单因素方差分析

第八章单因素方差分析

8.1黄花蒿中所含的青蒿素是当前抗疟首选药物，研究不同播期对黄花蒿种子产量的影响，试验采用完全随机化设计，得到以下结果(kg/小区)[47]：

重复2月19日3月9

3月28日4月13日

日

1 0.26 0.14 0.1

2 0.03

2 0.49 0.24 0.11 0.02

3 0.36 0.21 0.15 0.04

对上述结果做方差分析。

答：所用程序及结果如下：

options linesize=76 nodate;

data mugwort;

do date=1 to 4;

do repetit=1 to 3;

input yield @@;

output;

end;

end;

cards;

0.26 0.49 0.36

0.14 0.24 0.21

0.12 0.11 0.15

0.03 0.02 0.04

;

run;

proc anova;

class date;

model yield=date;

means date/duncan;

run;

One-Way ANOVA

Analysis of Variance Procedure

Class Level Information

Class Levels Values

DATE 4 1 2 3 4

Number of observations in data set = 12

One-Way ANOVA

Analysis of Variance Procedure

Dependent Variable: YIELD

Sum of Mean

Source DF Squares Square F Value Pr > F Model 3 0. 0.06171944 14.99 0.0012

Error 8 0.03293333 0.00411667

Corrected Total 11 0.

1

R-Square C.V. Root MSE YIELD Mean

0.848993 35.48088 0.06416 0.18083

Source DF Anova SS Mean Square F Value Pr > F DATE 3 0. 0.06171944 14.99 0.0012

One-Way ANOVA

Analysis of Variance Procedure

Duncan's Multiple Range Test for variable: YIELD

NOTE: This test controls the type I comparisonwise error rate, not the experimentwise error rate

Alpha= 0.05 df= 8 MSE= 0.004117

Number of Means 2 3 4

Critical Range .1208 .1259 .1287

Means with the same letter are not significantly different.

Duncan Grouping Mean N DATE

A 0.37000 3 1

B 0.19667 3 2

B

C B 0.12667 3 3

C

C 0.03000 3 4

对于方差分析表中各项内容的含义，在“SAS程序及释义”部分已经做了详细解释，这里不再重复。如果有不明白的地方，请复习“SAS程序及释义”的相关内容。

SAS分析结果指出，不同播种期其产量差异极显著。多重比较表明，2和3间差异不显著，3和4间差异不显著，1和其他各组间差异都显著。以上结果可以归纳成下表。

变差来源平方和自由度均方 F P

播期间0.185 158 33 3 0.061 719 44 14.99 0.001 2

重复间0.032 933 33 8 0.004 116 67

总和0.218 091 67 11

多重比较：

1 2 3 4

8.2下表是6种溶液及对照组的雌激素活度鉴定，指标是小鼠子宫重。对表中的数据做方差分析，若差异是显著的，则需做多重比较。

鼠号

溶液种类

Ⅰ(ck)ⅡⅢⅣⅤⅥⅦ

1 89.9 84.4 64.4 75.

2 88.4 56.4 65.6

2 93.8 116.0 79.8 62.4 90.2 83.2 79.4

3 88.

4 84.0 88.0 62.4 73.2 90.4 65.6

4 112.6 68.6 69.4 73.8 87.8 85.6 70.2 答：所用程序及结果如下：

options linesize=76 nodate;

data uterus;

infile 'e:\data\exr8-2e.dat';

do solution=1 to 7;

do repetit=1 to 4;

input weight @@;

output;

end;

end;

run;

proc anova;

class solution;

model weight=solution;

means solution/duncan;

run;

The SAS System

Analysis of Variance Procedure

Class Level Information

Class Levels Values

SOLUTION 7 1 2 3 4 5 6 7

Number of observations in data set = 28

The SAS System

Analysis of Variance Procedure

Dependent Variable: WEIGHT

Sum of Mean

Source DF Squares Square F Value Pr > F Model 6 2419.10500 403.18417 2.77 0.0385 Error 21 3061.30750 145.77655

Corrected Total 27 5480.41250

R-Square C.V. Root MSE WEIGHT Mean 0.441409 15.03118 12.0738 80.3250 Source DF Anova SS Mean Square F Value Pr > F SOLUTION 6 2419.10500 403.18417 2.77 0.0385 The SAS System

Analysis of Variance Procedure

Duncan's Multiple Range Test for variable: WEIGHT

NOTE: This test controls the type I comparisonwise error rate, not the experimentwise error rate

Alpha= 0.05 df= 21 MSE= 145.7765

Number of Means 2 3 4 5 6 7

Critical Range 17.75 18.64 19.20 19.60 19.89 20.12

Means with the same letter are not significantly different.

Duncan Grouping Mean N SOLUTION

A 96.175 4 1

A

3