K = inverse of constant form of money velocity (V)
Y = Quantity of Aggregate Output Demanded
- Price(P) and Output Demanded (Y) are inverse = an increase in
price leads to decrease in output demanded
Nominal money Supply (M) : INCREASE leads to a right shift in AD curve, DECREASE leads to a left shift in curve
Money Velocity (K or 1/V) :INCREASE leads to a right shift in AD curve,
DECREASE leads to a left shift in curve
Sticky Prices and AGGREGATE SUPPLY in SHORT RUN
Unlike LRAS where output is fixed, PRICE is FIXED for SRAS: HORIZONTAL LINE
STICKY PRICES
50% of firms don't change prices or only change once in a year
WHY: Co-ordination failure(waiting for other firms to change price), Nominal contracts(prices fixed by explicit contracts), Costs of changing prices (penalties for firms that change prices)
Money supply, velocity, and aggregate output only effect AD, SRAS is not changed
AGGREGATE SUPPLY LONG RUN
Aggregate Supply in long run = LRAS
LRAS depends on factors of production (Capital(K) and Labor(L)
Since both K and L are constant and output is determined by K(-),L(-) : Output is constant as well -> Y(-)
THEREFORE, LRAS is a vertical line
A change in money supply, velocity, price only affects AD doesn't effect LRAS line
ALSO: Output depends on technology
Aggregate Demand and Supply create DEMAND and SUPPLY SHOCKS
Shocks are EXOGENOUS changes in aggregate supply or demand
Supply Shock
Changes the cost of production, prices of G+S
UNFAVORABLE supply shocks
Increase cost of production, increase prices
EX) Drought, Environmental protection law, Increase in international cartel prices
FAVORABLE supply shocks:
Decrease cost of production(G+S), decrease prices
EX) Breakup of international cartel
Demand Shock
Positive demand shocks result in increase in AD, negative demand shocks Vice versa
Ex) Increase M = Increase AD (positive), Decrease V = Decrease AD (negative)
Exception: changing SUPPLY leads to a change in SRAS
EX) INCREASE in oil prices B/C of DECREASE in SUPPLY leads to INCREASING SRAS = Stagflation (Inflation + Recession)
Stabilization policies
Purpose: REDUCE the IMPACT of fluctuations in SHORT RUN
(Output returns to equilibrium)
2 Types of Policies
MONETARY POLICY
Works by changing the money supply
If output greater than equilibrium (Y > Y(-)),
INCREASE money supply (Expansionary Policy
If output less than equilibrium, DECREASE
money supply (Contractionary Policy)
FISCAL POLICY
Change in government spending levels, taxation
Y > Y(-), INCREASE G
Y < Y(-), DECREASE G
Easier to stabilize positive shocks than negative shocks
EX 1) INCREASE velocity = INCREASE in AD, to adjust: DECREASE money supply,
Price and Output at Equilibrium
EX 2) DECREASE velocity = DECREASE in AD, to adjust: INCREASE money supply
Output at Equilibrium, Price remains higher than equilibrium
Long Run = Prices are flexible and respond to changes to supply and
demand, output is constant
Short Run = Prices are fixed/STICKY at a predetermined level
Short Run Fluctuations are the business cycle
IF Y>Y(-) = LOW unemployment, HIGH demand, DECREASE in prices (Expansion)
If Y< Y(-) = HIGH unemployment, LOW demand, INCREASE prices (Recession)
Long Run: change is determined by movementalong the AD line
Short Run: change is determined by shifting the AD line