A post-Keynesian alternative to the New consensus on monetary policy Marc Lavoie University of Ottawa.

A post-Keynesian alternative to the New consensus on monetary policy

Marc Lavoie

University of Ottawa

What is the New consensus?

• New Keynesian “consensus-type model”, where policy reaction functions are “an essential part of the macroeconomic system”.

• Also called, the New Keynesian Synthesis

• J.B. Taylor, Blinder, D. Romer, Woodford, Meyer.

How is the New consensus linked to post-Keynesian theory?

• Positively

• “The main change is that it replaces the assumption that the central bank targets the money supply with an assumption that it follows a simple interest rate rule” (Romer 2000: 154).

• Negatively• The New consensus

reproduces accepted dogma among neoclassical economists, la pensée unique as the French say.

How is the New consensus linked to post-Keynesian theory ?

(2) About the reaction function

• Post-Keynesians• There is an interest

rate reaction function because it cannot be otherwise. Money supply targeting is impossible in principle and in practice.

• New Consensus• There is an interest

rate reaction function because interest rate targeting is more successful to dampen shocks to money demand than money supply targeting.

La pensée unique

• Expansionary fiscal policy only leads to higher inflation rates and higher real interest rates in the long run;

• More restrictive monetary policy only leads to lower inflation rates in the long run.

The new consensus: summary

• The new consensus is simply a variant of monetarism;

• but without any causal role for money.

• It is monetarism without money.

New consensus model

• IS function:

• g = g0 r + 1

• Vertical Phillips curve

• d/dt = (g gn) + 2

• Central bank reaction function:

• r = r0 + 1( T) + 2(g gne)

New consensus model:An alternative version (Setterfield)

• IS function:

• g = g0 r + 1

• Vertical Phillips curve

• d/dt = (g gn) + 2

• Central bank reaction function:

• dr = 1( T) + 2(g gne)

Implicit tothe New Keynesian model

• A natural real interest rate

• r0 = rn = (g0 gn)/

• which implies (g gn) = (r – rn)

• A natural growth rate, given by supply-side factors

• gn = a constant

Figure 5: The hidden consensus equation

0

gn

gn

2000 survey of AEA economists

• Question: Real GDP eventually returns automatically to potential real GDP?– Agree: 63 %– Disagree: 37 %

– Journal of Economic Education, Fall 2003

2000 survey of AEA economists

• Question: There is a natural rate of unemployment to which the economy tends in the long run ?– Agree: 68 %– Disagree: 32 %

Figure 1: The graphical new consensus with r = r0 + 1( T)

IS

AD

rr

g

g

RF

MP

gnStart with the historically given rate of inflation

Figure 2: New consensus with rising MP curve

IS

AD

rr

g

g

RF MP

gn

Figure 3A: Impact of a rise in effective demand:There is a lag in inflation

IS

AD

rr

g

g

RF

MP

gn

IA

g2

1

3

r3

r1

AB

A

B

Figure 3: Impact of a rise in effective demand

IS

AD

rr

g

g

RF

MP

g3=gn

IA

g2

1

3

r3

r1

A

B

C

A

BC

Figure 4A: Bringing back inflation to its target rate

IS1

AD2

r4r

g

g

RF1

MP

gn

IA

g2

T

3

r1

r3

AB

C

A

BC

g4

D

D

AD1 AD4

IS2

RF4

Figure 4: Bringing back inflation to its target rate

IS1

AD2

r4r

g

g

RF1

MP

gn

IA

g2

T

3

r1

r3

AB

C

A

BC

g4

D

D

AD1 AD4

IS2

RF4

D

Post-Keynesian alternatives

• (1): Reject the vertical Phillips curve and replace it with a long-run downward-sloping Phillips curve (Setterfield)

• Or,

• (2) Endogenize the natural rate of growth gn (Lavoie)

Similarity with PK critique of natural rate of unemployment

• Hargreaves-Heap (Economic Journal 1980)

• Cottrell (JPKE, 1984-85)

• dUn /dt = (U Un) + 3

Post-Keynesian views

• “Disequilibrium adjustment paths can affect equilibrium outcomes” (Colander, 1996: 60), leading to multiple equilibria and to path-dependent equilibria.

• “The natural rate of growth is ultimately endogenous to the demand-determined actual rate of growth” (Setterfield, 2002: 5)

Post-Keynesian views II• “Neoclassical growth economists on the one

hand, ... treat the rate of growth of the labour force and labour productivity as exogenous to the actual rate of growth....

• Economists in the Keynesian/post-Keynesian tradition, ... maintain that growth is primarily demand driven because labour force and productivity growth respond to demand growth” (León-Lesdema and Thirlwall, 2002).

2000 survey of AEA economists

• Question: Changes in aggregate demand affect real GDP in the short run but not in the long run ?– Agree: 62 % (potential growth is given)– Disagree: 38 % (potential growth is affected

by short-run effective demand)

The alternative PK model

g = g0 r + 1

d/dt = (g gn) + 2

r = r0 + 1( T) + 2(g gn)

r0 = rnT = (g0 gn)/

dgn /dt = (g gn) + 3

d d

d d

d dg t

g t

g

g

t

n n

/

/

( ) ( ) ( / )

1

1

1

1 12 1

2

2 1

2

3 2 1

2

3

PK model becomes a system of two differential equations

PK model becomes a system of two differential equations

• The dynamics of this system are pretty straightforward, because the determinant of this system is zero;

• and because its trace, is always negative.

• The amended new consensus model displays a continuum of equilibria. The model is said to contain a zero root.

• As the long-run equilibrium is not predetermined anymore, the steady-state rate of accumulation now depends on transitional dynamics, which cannot be ignored: short-run events have a qualitative impact on long-run equilibria. It is common to speak of ‘path-dependence’ for such a characteristic. It is possible to show that this kind of model displays hysteresis in the sense of a ‘permanent effect of a transitory shock’ (Olivier 1999).

An example of hysteresis

• For instance, a temporary increase in the rate of price inflation that would arise independently of excess demand pressure would have permanent effects on the natural rate of growth and the natural real rate of interest.

Another example

• Monetary policy now has real effects that go beyond its impact on the inflation rate.

• Zero-inflation or low-inflation targeting has a negative impact on the real economy, bringing in high real rates of interest and low real rates of growth.

Figure 6: Path-dependence, likely case

g

gndg = 0dgn = 0

gnE

gn

gAgnAgnBgB

A

A*B

B*

E

Figure 8A: Reducing the inflation target: PK model

IS

AD

rr

g

gnC

C

E

rB

rC

C

EB

E

gnE

B

rE

T

gB

C

rB*RF2

g

AD2

Figure 8: Reducing the inflation target: PK model

IS

AD

rr

g

RF3

gnB gnC

C

E

rB

rC

C

EB

E

B*

gnE

B

rE

T

gB

C

rB*

B*

RF2

g