Title: Some instability puzzles in Kaleckian models of growth and distribution
1Some instability puzzles in Kaleckian models of
growth and distribution
- Eckhard Hein, Marc Lavoie and Till van Treeck
2The Kaleckian model
- Three essential equations
- A pricing function (income distribution)
- A saving function
- An investment function
- The actual rate of capacity utilization is
endogenous, determined by demand, even in the
long run, and so in general will not be equal to
the normal rate of capacity utilization - Consequences the paradox of thrift, and under
some specifications, the paradox of costs
3Justification
- The Kaleckian model of growth has become a
workhorse of heterodox economics since the early
1980s, proving to be highly flexible. - Some authors claim however that one may be
Kaleckian or Keynesian in the short run but
needs to be Classical in the long run (Duménil
and LĂ©vy 1999, Shaikh 2007). - Others argue that the current dominance of the
Kaleckian model () is unfortunate for
post-Keynesian and Structuralist macroeconomics
(Skott 2008). - The purpose of this paper is to show that
these opinions are premature.
4Consequences of the critique
- Somehow the actual rate of capacity utilization
must be brought back to its normal rate - Somehow Harrods warranted rate of growth must
constrain the economy, and the classical equation
must hold - gw s/v sprn
- The paradoxes of thrift and of costs dont hold
anymore
5Outline
- We distinguish Keynesian and Harrodian
instability - We look at the various mechanisms that have been
suggested to bring back the actual rate of
utilization to its normal rate - We question the need for such a mechanism
- We offer alternative mechanisms that retain
Kaleckian features
6Instability
- There have been two somewhat related kinds of
criticisms - Keynesian stability (the slope of the saving
function is steeper than that of the investment
function), as assumed in Kaleckian models, is
doubtful. - Harrodian instability (the investment function
shifts out if u gt un)), as assumed away by
Kaleckians, is likely. - Therefore, there must exist some other mechanism
that brings back the economy towards its normal
rate of capacity utilization (shifting back in
the investment function, or shifting the saving
function)
7Keynesian instability Short period
g
gi
gs
gi(ue)
g
u
u
uK
ue
8Harrodian instability
g
gs
C
g3
gi
?3
g2
?2
B
?0g0
A
u
u1
un
u2
u3
9Consequences
- Whether there is Keynesian or Harrodian
instability, the consequences are the same a
boost in effective demand leads to an ever-rising
rate of accumulation and rate of utilization. - In practice, the two kinds of instability may be
difficult to disentangle.
10Some classical mechanisms designed to bring
back utilization to its normal rate
- Mechanisms acting on the saving function
- The Cambridge price mechanism, acting on the
profit margin - The retention rate solution, acting on the
overall propensity to save
11The Cambridge price mechanism
- (Robinson 1956, Kaldor 1956 Harcourt/Kenyon
1977, Eichner 1976, Wood 1975, Marglin 1984,
Skott 1989) - The profit margin rises as long as u gt un, thus
rotating the saving function. - The paradox of thrift is only retained if
accumulation depends on the profit rate - The mechanism has been described either as an
ultra-short run mechanism, or as a long-run
mechanism. - The profit margin, hence real wages fall, when
employment rates and growth are high. Doubtful?
,
12The retention rate solution
- This is the Shaikh I solution (2007)
- This classical synthesis allows us to preserve
central Keynesian arguments such as the
dependence of savings on investment and the
regulation of investment on expected
profitability, without having to claim that
actual capacity utilization will persistently
differ from the rate desired by firms (Shaikh) - The retention ratio of firms rises as long as u gt
un, thus rotating the saving function - However, the paradoxes of saving and of costs
disappear, because g ?rrn - Doubtful?
13Shaikh I solution
g
gs
gi
g1
g2
g0
u
u1
un
14More classical mechanisms designed to bring
back utilization to its normal rate
- Mechanisms acting on the investment function
- Monetary authorities get scared of inflation and
raise real interest rates - Capitalists get scared of full employment and
reduce the rate of growth of output - Capitalists have perfect foresight and revise
their sales expectations
15Monetary authorities get scared of inflation, and
raise real interest rates, thus lowering
investment
- The Duménil and Lévy (1999) mechanism
- Similar to the New consensus mechanism
- Also has resemblance with Robinsons inflation
frontier - Both the paradoxes of thrift and of costs get
wiped out
16The Duménil and Lévy mechanism low saving rates
lead to high growth in the short run, but lower
growth in the long run
g
gs
gi
g1
g0
g2
u
u1
us
17Drawbacks of the Duménil and Lévy mechanism
- Higher rates of utilization may not mean higher
or accelerating inflation rates (horizontal
segments in the Phillips curve) - Higher rates of interest may not succeed in
slowing down demand (it may increase consumer
demand instead) - When demand needs to be pumped up, it may be
impossible to lower real interest rates
sufficiently (zero lower-bound problem) - Raising the interest rate is likely to lead to a
lower normal rate of utilization (a higher
NAIRU), as firms raise their target profit
margins, and there is no guarantee that the
actual rate will converge to this evolving normal
rate (Hein 2006, 2008).
18Capitalists get scared of full employment and
reduce the rate of growth of output
- This is the Skott mechanism (1989, 2007, 2008).
- In the mature economy, the rate of output
growth is a positive function of the profit share
and a negative function of the employment rate. - If the employment rate rises above its steady
state value, capitalists reduce output growth,
sales growth declines, the actual rate of
utilization falls, and the constant in the
investment function starts to shrink. - The cause firms have increasing problems to
recruit additional workers, workers and labour
unions are strengthened vis-Ă -vis management,
workers militancy increases, monitoring and
surveillance costs rise, and hence the overall
business climate deteriorates.
19Drawbacks of the Skott mechanism
- It is not clear why output growth should be a
positive function of the profit share this
excludes Kaleckian effects by assumption. - It is not clear why high employment rates,
accompanied by more powerful workers and labour
unions, should induce capitalists to reduce
output growth in the first place. - One would rather think that high employment rates
generate rising nominal wage growth. This should
cause either rising inflation or a falling profit
share, or both. - But the latter would intensify Harrodian
instability! - What about labour supply growth being driven by
labour demand growth?
20Capitalists have perfect foresight and revise
their sales expectations
- The Shaikh II (2007) mechanism
- Based on a special Hicksian stock-flow
investment adjustment function. - Investment depends on the rate of utilization and
the growth rate of sales that will be realized in
the current period - If so, it can be shown that the actual rate of
capacity utilization necessarily converges to its
normal rate.
21Shaikh II
Ă»
u
0
-
gs
g
gkal
gi gy ?u(u-un)
? gk0 gy0
gk2
gy2
gk3 gy3
u
u1
u2
ukal
un
22Drawbacks of the Shaikh II mechanism
- Firms must know the growth rate of their sales.
- But this rate depends on the investment
expenditures of all other firms. - Thus, each firm needs to know what all other
firms simultaneously decide. - The informational requirements are huge.
- The behaviour of managers is unlikely following
a period of rising rates of utilization, firms
need to believe that sales will grow more slowly. - If firms act in some adaptive way, Harrodian
instability reappears.
23Questioning the necessity of any adjustment of u
towards un
- Provisional equilibrium everything moves anyway
(Chick and Caserta 1997) - Other stock-flow norms in growth models are not
realized, even when agents try to achieve them
wealth/income targets (Godley) - There is a large range of acceptable desired or
normal rates of capacity utilization (Dutt
1990). - A firm may operate each running plant at optimal
capacity (cost-minimizing), while being unable to
to run all plants (idle capacity) (Caserta 1990).
24Acceptable range
- The stock adjustment principle, with its
particular desired level of stocks, is itself a
simplification. It would be more realistic to
suppose that there is a range or interval, within
which the level of stock is comfortable, so
that no special measures seem called for to
change it. Only if the actual level goes outside
that range will there be a reaction. (Hicks
1974, p. 19)
25Even Sraffians accept that firms usually have
idle capacity
- It is virtually impossible for the
investment-saving mechanism to result in an
optimal degree of capacity utilization. It is,
rather, expected, that the economy will generally
exhibit smaller or larger margins of unutilized
capacity over and above the difference between
full and optimal capacity. (Kurz 1994) - One must keep in mind that although each
entrepreneur might know the optimal degree of
capacity utilization, this is not enough to
insure that each of them will be able to realize
this optimal rate. (Kurz 1993)
26Still, we do not wish to sweep the problem under
the carpet
- There are mechanisms that can bring together the
actual and the normal rates of capacity
utilization, by making the normal rate endogenous
to the values taken by the actual rate (Lavoie
1992, 1996, 2003 Cassetti 2006, Commendatore
2006). - So normal rates adjust to the actual rates.
- With some specifications, these hysteresis models
safeguard both the paradoxes of thrift and of
costs. - A critique of these has been why would firms
modify the normal rate of utilization just
because it has not been achieved recently (Skott
2008)?
27A possible answer because firms have multiple
targets !
- This is the Dallery and van Treeck (2008) model,
partly based on Lavoie (2003). - Firms may set themselves target or normal
rates of utilization. - But they also may have other targets, such as
target rates of return (rsf), required for
financing growth or imposed or suggested by
shareholders. - In addition, workers may have a target real wage,
equivalent to some target rate of return (rw),
which stops the firms from achieving their target
rate of return. - Thus, to follow Skotts analogy, although I may
always be late arriving at work (u gt un) , I may
be unable to leave any earlier to arrive on time
(u un), because of other commitments (rw, rsf).
28The Dallery and van Treeck (2008) mechanisms
- Firms may raise their target rate of return when
the actual rate is above the target. - By doing this, running at an over-normal rate of
utilization, they may succeed in achieving the
target rate of return. - Firms may also decide to decrease their retention
ratio sf (thus distributing more dividends), as
long as the actual profit rate is below the
target. - This is similar to the Shaikh I mechanism. But
the utilization rate remains endogenous here.
29Conclusion- The Kaleckian model is more flexible
than the critics of the textbook version
supposeFurther developments - Financial
sector instability and real instability- Role
of labour supply (endogeneity channels)-
Integration of economic policies