ch1Introduction(中级宏观经济学,香港中文大学)-文档资料

• A common measure of aggregate output is GNP.
• Gross National Product (GNP) measures the value of output produced by domestic factors of production, whether or not the production takes place inside the country’s borders.
Cooper & John)
Chapter 2 Measurement
Measuring Gross Domestic Product (GDP)
• National Income Accounting is a process of measuring the total quantity of goods and services produced for the market in a given country over a given period of time.
countries – the economic interactions among nations – the effects of fiscal and monetary policies
• Macroeconomics differs from microeconomics in that it deals with the overall effects on economics of the choices that all economic agents make, rather than on the choices of individual consumers or firms.
• Expenditure approach: GDP is the total spending on all final goods and services production in the economy
Total expenditure = C + I + G + NX
• Income approach: GDP can be computed by adding up all incomes received by economic agents contributing to production. Incomes include: – compensation of employees, proprietors’ income, rental income, corporate profits, net interest, indirect business taxes and depreciation.
– Product Approach – Expenditure Approach – Income Approach
• Product approach: GDP is the sum of value added to goods and services in production across all productive units in the economy.
Gross National Product, Economic Growth and Business Cycles
• The most basic set of facts in macroeconomics has to do with the behavior of aggregate economic activity over time.
• Coconut is both an intermediate good in the restaurant and a final consumption good.
• Current year production of coconuts = 10 million • Unit Price of coconut = $ 2.00
• Keynesian Sticky-Price Theory (Keynes, Hicks & Samuelson)
• Money Surprise Theory (Friedman & Lucas) • Real Business Cycle Theory (Prescott & Kydland) • Keynesian Coordination Failure Theory (Diamond,
Remarks: the value of intermediate goods used in production must be subtracted from the value of all goods produced in the economy, if not there would be doublecounting.
• Gross Domestic Product (GDP) is the dollar value of final output produced during a given period of time within a country.
• There are 3 distinct approaches to measure GDP:
• The trend in the log of real per capita GNP is shown as a colored line, while the log of actual real per capita GNP is the black one.
• The lower graph shows only the percentage deviations from trend in real per capita GNP.
– The consumers and firms in the economy, who are assumed to optimize
– The sets of goods that consumers wish to consume – Consumers’ preferences over goods – The technology available to firms for producing goods – The resources available • Competitive Equilibrium: all agents (consumers and firms) act as price-takers, and prices clear markets.
Disagreement in Macroeconomics
• There is little disagreement in macroeconomics concerning the general approaches to modeling growth.
• There is much controversy concerning business cycle theory and the role of the government policy in smoothing out cycles:
• One measure of aggregate economic activity is gross national product (GNP).
• The series of real GNP per capita for the U.S. over the period 19002002 is shown in the figure.
Macroeconomic Models
• Purpose: To capture the essential features of the world needed for analyzing a particular economic problem.
• To be useful then, a model must be simple. • Basic structure of a macroeconomic model:
Two Useful Transformation of Data
1) Taking natural logarithm of time series.
• The slope of the graph of the natural logarithm of a time series yt is a good approximation to the growth rate of yt when the growth rate is small.
• In particular, we want to make predictions on those effects that are consistent with individual decisions.
• To achieve this, we must work our way up from decision making at the micro-level, then aggregating these decisions to arrive at the macroeconomic effects of the policy change.
• Since if yt yt-1, we have
loygt loygt1ytyty1t1.
2) Detrending • the process of decomposing the
series into 2 components: the growth (or trend) component, and the business cycle component.
Chapter 1
Introduction
Fra Baidu bibliotek What is Macroeconomics ?
• Macroeconomics focuses on
– the aggregate behavior of consumers and firms – the behavior of government – the overall level of economic activity in individual
Microeconomic Principles
• Macroeconomic behavior is the aggregation of microeconomic decisions made by all the consumers and firms in the economy. Very often, we are interested in the macroeconomic effects of a policy change.
GNP = GDP + Net factor payments from abroad to domestic residents
Numerical Example 1
• Consider an economy consisting of a coconut producer, a restaurant, consumers and a government.
• Long-run growth refers to the increase in a nation’s productive capacity and average standard of living over a long period of time.
• Business cycles refer to the short-run ups and downs in aggregate economic activity.