Encyclonomic WEB*pedia: INDUCED GOVERNMENT PURCHASES

INDUCED GOVERNMENT PURCHASES:
Government purchases that depend on income or production (especially national income and gross domestic product). That is, changes in income induce changes in government purchases. Induced government purchases reflect the observation that the government sector (especially state and local governments) is inclined to use tax revenue, which increases with income, for purchases. They are measured by the marginal propensity for government purchases (MPG) and are reflected by the positive slope of government purchases line. The alternative to induced government purchases is autonomous government purchases, which do not depend on income.
Induced government purchases are government purchases by the government sector that are based on the level of income or production. This is one of two basic classifications of government purchases. The other is autonomous government purchases, government purchases that are NOT based on the level income or production. In other words, government purchases can be divided into: (1) expenditures which are undertaken by the government sector regardless of the level of aggregate production and (2) an adjustment of expenditures (more or less) that results because aggregate production and income changes.
Government purchases are commonly assumed to be totally autonomous in the introductory analysis of Keynesian economics. That is, any induced government purchases that realistically exist are ignored. Doing so not only simplifies the analysis, but also places the focus on how and why autonomous government purchases changes, and how such changes affect the macroeconomy. More sophisticated, and realistic, analysis then includes induced government purchases.
Government purchases are induced because governments, especially state and local governments, are prone to use tax revenues generated by a growing, expending economy to finance government purchases. If the economy is growing and expanding, then income is greater and so too is tax revenue. Because most state and local governments face legal constraints that restrict spending to tax revenue, more revenue means more spending and less revenue means less spending. As such, government purchases are induced by the increase in aggregate income and production. While induced government purchases are not nearly as big or important as induced consumption, they do play a key role in Keynesian economics. They affect the determination of equilibrium and the magnitude of the multiplier',500,400)">multiplier process.
Induced government purchases are reflected by the slope of the government purchases line and the marginal propensity for government purchases (MPG). The MPG is important to the slope of the aggregate expenditures line which also affects the value of the expenditures multiplier.
Induced: An Equation
One way to illustrate induced government purchases is with a linear government purchases equation, such as the equation presented here:
G = g + hY
where: G is government purchases, Y is income (or aggregate production), g is the intercept, and h is the slope.
As with any linear equation, the two key parameters that characterize this government purchases equation are slope and intercept. Induced government purchases are indicated by the slope of the government purchases equation. Autonomous government purchases are indicated by the intercept.
An Induced Slope: The slope of the government purchases equation (h) measures the change in government purchases resulting from a change in income. If income changes by $1, then government purchases changes by $h. This slope is generally assumed and empirically documented to be greater than zero, but less than one (0 < h < 1). It is conceptually identified as induced government purchases and is measured as the marginal propensity for government purchases (MPG).

An Autonomous Intercept: The intercept of the government purchases equation (g) measures the amount of government purchases undertaken if income is zero. If income is zero, then government purchases are $g. The intercept is generally assumed and empirically documented to be positive (0 < g). It is conceptually identified as autonomous government purchases.
Induced: A Line
Government Purchases Line

Another common way to identify induced government purchases is with a government purchases line, such as the one presented in the exhibit to the right. The red line, labeled G in the exhibit, indicates government purchases that are completely autonomous. There are no induced government purchases indicated by this line. As such, the slope of the government purchases line is zero (h = 0). The intercept of this horizontal line indicates autonomous government purchases, which is $2 trillion in this exhibit.
However, government purchases are realistically induced by the level of income and production in the economy. An induced government purchases line has a positive slope. And because government purchases are only modestly induced by income and production, an induced government purchases line has a slight slope. A click of the [Induced A Little] button illustrates induced government purchases (with a comparison to the autonomous government purchases line).
The new red line, labeled G' in the exhibit, is the positively-sloped government purchases line for the equation: G = 2 + 0.05Y. This line indicates that greater levels of income generate greater government purchases by the government sector.
The two primary characteristics of this government purchases line--slope and intercept--indicate the difference between autonomous government purchases and induced government purchases.
An Induced Slope: The slope of this new government purchases line is positive, but less than one. In this case the slope is equal to 0.05, a $1 change in aggregate production induces a $0.05 change in government purchases. This positive slope indicates induced government purchases. Moreover, the slope of the line is also the marginal propensity for government purchases (MPG).

An Autonomous Intercept: This new government purchases line, like the original line, intersects the vertical axis at a positive value of $2 trillion. And once again this indicates autonomous government purchases.
Other Induced Expenditures
Investment is one of several induced expenditures. The other three aggregate expenditures--consumption expenditures, government purchases, and net exports--are also induced by income and production.
Consumption is unquestionably the most important induced expenditure. It is not only the largest of the four aggregate expenditures, but it is also the most induced of the four. It captures the fundamental psychological law and triggers the largest change in expenditures resulting from a change in income or production.

Investment is induced by income because an expanding economy generally boosts business profit, which is then used for investment expenditures on capital goods.

Net exports, the difference between exports and imports, are induced through imports, which are induced in the same fashion as government purchases. An increase in income is not just used to purchase domestic goods, but also imported goods.
Other components of the macroeconomy are also related to, or induced by, income and production. An important one is saving, which is the other side of consumer behavior. Consumption and saving are both induced by income. The psychological law states that an increase in income is used both for extra consumption and extra saving. A second induced part of the macroeconomy is taxes. In particular, sales and income taxes are directly related to income. More income invariably means more taxes. Another is the demand for money. Because expenditures use money, an increase in income not only induces expenditures, it also induces the demand for money.
Check Out These Related Terms...
     | autonomous government purchases | government purchases line | marginal propensity for government purchases | induced expenditures | induced consumption | induced investment | induced imports | slope, government purchases line | intercept, government purchases line | injections | leakages |
Or For A Little Background...
     | Keynesian economics | circular flow | aggregate expenditures | government purchases | government expenditures | government consumption expenditures and gross investment | macroeconomics | government sector | national income | gross domestic product | taxes | business cycles |
And For Further Study...
     | aggregate expenditures | aggregate expenditures line | government purchases determinants | Keynesian model | Keynesian equilibrium | injections-leakages model | aggregate demand | paradox of thrift | fiscal policy | multiplier |
Recommended Citation:
     INDUCED GOVERNMENT PURCHASES, AmosWEB Encyclonomic WEB*pedia, http://www.AmosWEB.com, AmosWEB LLC, 2000-2025. [Accessed: December 16, 2025].