why investment is constant in AD schedule Related: Point of aggregate...
Why Investment is Constant in AD Schedule?
The aggregate demand (AD) curve shows the relationship between the price level and the quantity of real GDP demanded by households, firms, and the government. One of the components of AD is investment, which is a function of interest rates and expected returns on investment. However, in the short run, investment is assumed to be constant, and this has important implications for the shape of the AD curve.
Investment Determinants
Investment is the purchase of new capital goods, such as machinery, equipment, and buildings, that are used to produce goods and services. The level of investment depends on several factors:
- Interest rates: Higher interest rates reduce the quantity of investment demanded because they increase the cost of borrowing.
- Expected returns on investment: If firms expect higher profits from investment, they will be more likely to invest.
- Business confidence: If firms are optimistic about the future, they may be more willing to invest.
- Technology: New technologies may create opportunities for investment.
- Government policy: Tax incentives or subsidies may encourage investment.
Short-Run Assumption
In the short run, it is assumed that investment is constant because it takes time for firms to adjust their investment plans in response to changes in interest rates or expected returns. In addition, some investment projects may be already underway or committed, and cannot be easily cancelled or postponed.
Implications for the AD Curve
If investment is assumed to be constant, then any change in the price level will not affect the quantity of investment demanded. Therefore, the AD curve will be relatively steep, because changes in the price level will have a large impact on the quantity of real GDP demanded.
However, in the long run, investment can adjust to changes in interest rates and expected returns, and the AD curve can become flatter. This is because changes in the price level will affect the quantity of money demanded, which in turn will affect interest rates, and therefore investment.
Therefore, the short-run assumption of constant investment helps to explain the steep slope of the AD curve in the short run, while the long-run adjustment of investment helps to explain the flatter slope of the AD curve in the long run.