Dynamic AD-AS Model: Fiscal Policy: Videos & Practice Problems

The dynamic Aggregate Demand and Aggregate Supply (ADAS) model provides a framework for understanding how fiscal policy can influence economic performance over time. In this model, it is essential to recognize that the economy generally experiences growth, leading to a rightward shift in long-run aggregate supply, short-run aggregate supply, and aggregate demand. This growth reflects the natural progression of the economy, where real GDP tends to increase year over year.

When the economy is in a recession, real GDP falls below its potential GDP, indicating underutilization of resources. In such scenarios, the government can implement expansionary fiscal policy to stimulate economic activity. This can be achieved through increased government spending or tax cuts. By boosting government expenditures, aggregate demand rises, as government purchases are a component of aggregate demand. Similarly, tax reductions enhance consumer spending, further elevating aggregate demand.

In the dynamic ADAS model, the initial equilibrium is characterized by a specific price level and real GDP. As the government enacts expansionary fiscal policy, the long-run aggregate supply shifts to the right, indicating an increase in potential GDP. However, during a recession, the increase in aggregate demand may not be sufficient to reach the new long-run equilibrium. This results in a short-run equilibrium where aggregate demand is still below potential GDP.

To visualize this, consider the initial equilibrium at point A, where the economy is not at full capacity. Following the implementation of expansionary fiscal policy, the short-run aggregate supply and aggregate demand curves shift rightward. If the government effectively stimulates demand, the economy can move towards a new equilibrium at point C, where all curves intersect, indicating that the economy has returned to its potential GDP.

Ultimately, the goal of fiscal policy in this context is to maintain economic stability by addressing recessions and inflationary pressures, ensuring that the economy operates at its full potential. Understanding these dynamics is crucial for analyzing the effectiveness of fiscal interventions in the economy.

In the context of a dynamic Aggregate Demand-Aggregate Supply (ADAS) model, rising inflation indicates that the economy is operating above its potential GDP. This situation arises when the short-run equilibrium exceeds the long-run equilibrium, leading to excessive GDP relative to potential GDP. To address this imbalance, contractionary fiscal policy is implemented, which involves reducing government spending and/or increasing taxes. These measures aim to lower aggregate demand, thereby helping to stabilize the economy and reduce inflation.

When aggregate demand is too high, it can lead to increased prices, necessitating a pullback to align with potential GDP. Initially, the economy may be at an equilibrium point (Point A) where the long-run aggregate supply (LRAS) and short-run aggregate supply (SRAS) intersect. As aggregate demand increases significantly, it shifts to a new level (Aggregate Demand 2), pushing the economy beyond its potential GDP (Point B). This results in higher price levels and inflation.

To counteract this, contractionary fiscal policy is employed, which effectively reduces aggregate demand. By decreasing government spending or increasing taxes, consumption is lowered, leading to a decrease in aggregate demand. This adjustment shifts the aggregate demand curve back towards equilibrium (Aggregate Demand 3), allowing the economy to stabilize at a new equilibrium point (Point C) that aligns with potential GDP.

At this new equilibrium, the price level is lower than it was at Point B, indicating a reduction in inflationary pressures. The relationship between expansionary and contractionary policies is fundamentally oppositional; while expansionary policies aim to stimulate demand, contractionary policies seek to rein it in to maintain economic stability.