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Working Paper 9118

RISK AVERSION, PERFORMANCE PAY,
AND THE PRINCIPAL-AGENT PROBLEM
by Joseph G. Haubrich

Joseph G. Haubrich is an economic advisor at
the Federal Reserve Bank of Cleveland. The
author thanks Linda Fuhr for typing
assistance.
Working papers of the Federal Reserve Bank of
Cleveland are preliminary materials circulated
to stimulate discussion and critical comment.
The views stated herein are those of the
author and not necessarily those of the
Federal Reserve Bank of Cleveland or of the
Board of Governors of the Federal Reserve
System.

December 1991

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ABSTRACT

This paper calculates numerical solutions to the principal-agent problem and
compares the results to the stylized facts of CEO compensation. The numerical
predictions come from parameterizing the models of Grossman and Hart and of
Holmstrom and Milgrom. While the correct incentives for a CEO can greatly
enhance a firm's performance, providing such incentives need not be expensive.
For many parameter values, CEO compensation need only increase by about $10
for every $1,000 of additional shareholder value; for some values, the amount
is 0.003 cents. The paper thus answers two challenges posed by Jensen: that
principal-agent theory does not yield quantitative predictions, and that CEO
compensation is insufficiently sensitive to firm performance.

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I. Introduction
The principal-agent paradigm lies at the center of corporate finance.
Its central problem of motivating a subordinate provides sharp insight into
issues surrounding debt, equity, dividends, executive pay, and regulators'
activities during the thrift debacle. Jensen and Murphy (1990) challenge this
paradigm, finding that the compensation of top executives increases a mere
$3.25 per $1,000 gain in shareholder wealth. This pay-performance sensitivity
of 0.003 is a far cry from the 1.0 predicted by the risk-neutral version of
principal-agent theory. Their estimate challenges broader versions of the
theory to predict anything quantitative at all.

In moving beyond risk

neutrality, "...theory says nothing about the magnitude of the pay/performance
relation" (Baker, Jensen, and Murphy [1988], p. 611).
Yet, as this paper shows, principal-agent theory

can yield

exact

quantitative predictions. Grossman and Hart (1983) provide such a solution
for a two-state,finite-action model. Once a few parameters are chosen,
quantitative results follow. Thus, it becomes possible to find what
principal-agent theory predicts for the cases Jensen and Murphy consider.
In the parameterized models, small amounts of risk aversion can result
in quite low values of pay sensitivity. The results in this paper thus
respond to both of the challenges issued by Jensen and Murphy: providing
quantitative predictions, and predicting low pay-performance sensitivity. The
results also confirm their intuition that incentives matter greatly for
executive performance and consequently for shareholder value.
One motive for pursuing the quantitative approach is the success it has

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found in related fields. Asset pricing has long benefited from a fruitful
interplay between empirical work and quantitative models.

So has public

finance, where authors from Mirrlees (1971) to Sheshinski (1989) have used
quantitative solutions to the "hidden type" (as opposed to the "hidden action"
type considered here) principal-agent problem to calculate the optimal income
tax.
The following section provides more detail on pay sensitivity. Section
I11 reviews the model and the needed analytical results, all of which follow
from Grossman and Hart. Section IV reports the numerical solutions, and
section V compares the results with similar calculations based on a model from
Holmstrom and Milgrom (1987).

Section VI concludes.

11. Performance Pay
The argument about pay sensitivity has both a descriptive and a
prescriptive component. In the descriptive part of their analysis, Jensen and
Murphy (1990) carefully gather data and assess the pay-performance sensitivity
for chief executive officers (CEOs) in the Forbes Executive Compensation
Survey, encompassing salary, bonus, stock options, insider stock holdings, and
dismissal probability. By the narrowest measure, salary plus bonus, which
excludes savings plans, thrift plans, other benefits, and stock holdings and
options, the pay-performance sensitivity is 0.0000135, or 1.35 cents per
$1,000 of shareholder value. By the broadest measure, which looks at changes
in CEO wealth and includes Forbes' "total compensation," stock options and
insider stock holdings, present value of changes in salary and bonus, and the
effects of dismissal, total pay-performance sensitivity is $3.25 per $1,000,
or 0.00325.

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The prescriptive part is emphasized more in Jensen's Harvard Business
Review article, "Eclipse of the Public Corporation" (1989).

He argues here

that publicly traded corporations do not resolve the conflict between
shareholders and managers as well as do leveraged buyout (LBO) associations.
In LBO associations, executive salaries are close to 20 times more sensitive
to performance than in public corporations. As Jensen states (p. 69), "It's
not hard to understand why an executive who receives $200 for every $1,000
increase in shareholder wealth will unlock more value than an executive who
receives $3.25."
In addition to suggesting that theory cannot explain the quantitative
fact, Jensen and Murphy also present qualitative evidence against a standard
principal-agent interpretation for executive pay.

They point out the superior

performance of LBO associations, the decline in equity holding among officers
over time, and the sparse use of additional information in compensation
schemes. The principal-agent model can potentially explain these results,
because parameter values can differ across firms and across time. This paper
generally avoids those issues, though section V briefly considers why
additional information may be ignored.

111. Model and Analytical Results
Though the principal-agent model is a natural one for executive
compensation, with shareholders as the principal and the CEO as the agent,
most versions have intractable solutions. Quantitative predictions do not
readily emerge from the implicit equations that define the sharing rules,
especially in models with a continuum of states. Grossman and Hart (1983,
sec. 4), however, provide a tractable solution to the two-state, finite-action

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case.

Choosing a few parameters and functional forms then results in a

quantitative prediction.
To appreciate both the scope and the limitations of the numerical
calculations, it helps to know the basic model structure and the theorems that
justify the later work.

Assumptions and Notation
The principal, or firm, has two gross profit levels, q1<q2.

The agent

can choose from a finite set A of actions, (al,az,
...a,,), which influences the
probability of good and bad profits.

These might be viewed as effort levels,

or different projects the CEO can approve. Formally, &(a)

denotes the

probability of state (profit level) i given action a.
The agent's utility depends on actions and on income, expressed as
U(a,I).

Solving the model requires some restrictions on U , expressed in

Assum~tionAl: U(a,I)=

G(a)+K(a)V(I),

where

i) V is real, continuous, strictly increasing, and concave on an open interval
(I,,

a);

ii)

LimI,,I,V(I)=-co;

iii) G and K are real, continuous on A and K>O;
iv)

For all a,b contained in A and all I,J contained in (I,,a),
G(a)+K(a)V(I)

LG(b)+K(b)V(I)

implies

This formulation makes preferences over income risk independent of
action (the converse is also true), and makes the agent risk averse.
The numerical calculations of section IV further specialize the utility

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function, setting either G=O or K=l. One useful function of this form is the
constant absolute risk aversion (CARA) type with
V (I)- -e-*I, ~(a)=e*a, so U(a,I)=

-e-*(l-a),

in which effort appears as negative income. The disutility of effort greatly
influences management compensation; treating effort as negative income makes
the resulting contract easier to interpret.
The agent also has a

c,derived from an alternative employment or

leisure-time activity he can turn to if he does not work for the principal. I
exclude actions so distasteful that the agent would never choose them, and to
keep the problem interesting I assume that some actions remain. This
particivation constraint is embodied in
Assumvtion A2:

For every action a contained in A, there is an I in (I,, Q)

such that G(a)+K(a)V(I)

1 c.

The final assumption puts some structure on the probability of profits.
Assumvtion A3:

For all a contained in A and i-1 ...n, &(a)

> 0.

This rules out the Mirrlees (1974) plan of imposing increasingly high
penalties with increasingly low probabilities as the agent takes actions

> 0 and A is finite, such a strategy

approaching the right one: Since &(a)
puts too much risk on the agent.

One major advance of Grossman and Hart is to focus on the cost of
getting the agent to choose a particular action. In the "first best" case, in
which the principal observes the action, the cost is simply the agent's
reservation price for a, denoted
CFB(~)=~[(v-~(a))/~(a) ] , where h=~-'.
Of course, the whole point of the principal-agent problem is that the
5

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principal cannot observe the action. She can only make payment dependent on
the realized output state, the gross profit level. This incentive scheme, a
set of payments contingent on the state (11,12),gives the agent utility
levels
v1=V(I1)
vz=V(Iz)

.

Although the principal cannot observe the action, she can design an
incentive scheme that induces the agent to choose that action. This defines
the second-best cost of an action a*, C(a*).

x
2

(1)

Choose v,, v2 to minimize

IIi ( a * ) h

i =l

vi)

subject to
2

Di ( a * ) v i ] 2 G ( a )

G(a*) + K(a*) [
i=l
2

G(a*) + K(a*) [

x ni

+

K(a) [

IIi(a)viIva'arA
i=l

( a * ) vi] t

i

i=l
v i e Range ( V ) V i .

The first constraint is the incentive compatibility constraint, which
states that the agent takes action a* only if that action gives a higher
payoff than any other action. The second and third constraints are the
participation constraints, which state that the agent must get a certain
minimum utility, and that there exists an income level that produces the
desired utility.
Several incentive schemes (I or v sets) may induce the agent to choose
action a* (that is, implement a*).
(infinurn or in£) of

mi

Define C(a*)

as the greatest lower bound

h(vi) on the constraint set of equation (1).

For an

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empty constraint set, set C(a*)

to infinity. In that case, the principal

cannot induce action a*.
A little terminology about the principal completes the basic notation.
Because the risk-neutral principal gets the gross profits, her expected
benefit from an agent's action is
B(a)

=

mi(a)qi.

The ovtimal action (second-best) maximizes the expected net benefit to the
principal,
B(a)-C(a).

General Results
The simple solution used below depends on some general theorems due to
Grossman and Hart. At least a passing familiarity with these ideas is
necessary in order to understand the range and restrictions on the results.
From the general n-state case, I take two main results. Proposition 1
states that assuming Al, A2, and A3, there exists a second-best optimal action
and a second-best optimal incentive scheme. Proposition 6 states that for
finite A, the agent is indifferent between the action he takes and some less
costly actions under the optimal incentive scheme.
Three results for the two-state case make possible an explicit
calculation of the solution. First, a definition: Action a is efficient if
the probability of a good outcome can be increased only by incurring a greater
cost. Proposition 10 states that assuming Al, A2, A3, and V are strictly
concave, with two states every second-best action is efficient.
The next propositions also restrict possible solutions. Proposition 11
states that under the conditions of Proposition 10, the agent obtains his

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reservation utility. Proposition 12 states that assuming Al, A2, and two
states, adding new actions a', such that CFB(a')

2 CFB(a) for all a in A ,

cannot make the principal worse off. That is, adding distasteful actions
won't encourage the agent to shirk but might give the principal more
information.

Solution Techniques for the Two-State, Finite-Action Case
Grossman and Hart have a simple plan for solving the principal-agent
problem. First, compute the cost C(a) for each action a. Then optimize the
net benefit, B(a)-C(a),

over all actions a.

Several special results make this

unusually easy in the two-state, finite-action case.
Proposition 6 , that the agent is indifferent between the chosen action
and some less costly action, combines with Proposition 10, that the agent
chooses only efficient actions, to drastically simplify the cost and
probability structure. Without loss of generality, we can assume that
CFB(al)<CFB(a2)<.

. .<CFB(%)

and correspondingly I12(al) < I12(a2) <

. . .< 112(%)

.

Because there is no conflict in getting the agent to take the least costly
(minimum effort) action al, C (al)=CFB(al).

This ties down C(al)

.

For the other actions, I use Proposition 6 and Proposition 11 to compute
C(ak).

For each action aj for j<k, find the I,, 1, pair that makes the agent

indifferent between ak and aj and that also sets that common expected utility
to

t.

Finding v, and v2, the utility levels that satisfy those two

conditions, involves solving two simultaneous linear equations.

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G ( a j ) + K ( a j ) [Dl( a j ) V1

+

n2 ( a j ) v21

=

-

U-

Solving for vl and v2 yields

The incentive scheme, or actual payments to the agent, comes from inverting
the utility function, setting I1=h(vl) and 12-h(v2)

.

This gives (k-1) different (vl,v2)pairs and hence (k-1) different
(11,12)pairs, one for each j<k.

Proposition 6 says that one of these pairs

must be the minimum cost-incentive scheme for ak; that will tell us C(ak).
Grossman and Hart show that incentive compatibility implies it is the pair
with the largest v2. With any other pair, the agent would prefer action aj to
action ak.
The (v1,v2)pair chosen for each action ak must then be checked against
the range of V.

For example, exponential or power utility functions are

always negative, but the above procedure sometimes demands strictly positive
utility. In that case, C(ak) is infinite: The principal cannot induce that
behavior from the agent. For the feasible vi's, cost is simply the expected
value of payments to the agent, or

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C(ak)

=

IIl(ak)vl + I12(ak)v2.

Once the second-best cost C(ak) is computed for each k, the problem
becomes straightforward. The principal chooses among a finite number of
actions to maximize B(a)-C(a).

IV. Numerical Solutions
Section I11 outlines a way to calculate exact quantitative solutions to
simple principal-agent models.

I now choose the parameters and perform the

calculations, applying the model to the executive compensation problems of
Jensen and Murphy.
The model has many free parameters.

These include the payoff, risk

aversion, disutility of effort, reservation utility, and outcome state
probabilities, as well as the effects of action on probabilities, number of
actions, and functional forms. Even those parameters previously estimated,
such as risk aversion, do not have standard, accepted values. Others, such as
the CEO's effect on share value, are conceivably measurable, but serious
practical problems prevent measurement.

Still others, such as the number of

actions, have no real empirical counterpart.
To overcome this, I present a variety of solutions for different
parameter values. When possible, I use the estimates of Jensen and Murphy,
such as the standard deviation of shareholder value and the average
compensation of CEOs. For parameters they do not estimate, such as disutility
of effort, I take values from their illustrative examples. For the remaining
parameters, such as risk aversion, I use a range of values. Thus, the model
predicts outcomes for the cases Jensen and Murphy discuss using parameter
values that are close to what most people would consider sensible.

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Basing the parameter values on the Jensen and Murphy examples represents
only a small subset of possible predictions.

Some later examples explore the

broader range of possibilities by using more extreme values.

Base Case

The first (base) case has two states and three actions. The standard
deviation of shareholder wealth in the Jensen and Murphy samples is $200
million (p. 244).
deviation is

(x-y).

d

For a two-point distribution with x > y, the standard

m

(x-y).

For p=1/2, this further simplifies to (

1

3)

Putting all monetary rewards in units of $1 million ($lo6), I choose

gross profit levels of 300 and 700.
Jensen and Murphy do not specify a reservation wage; I use the median
CEO compensation for their sample, $490,000. For later robustness checks, I
use $250,000, which is Business Week's estimate of Sanford Grossman's academic
salary (Byrne [1988]).

I use constant absolute risk aversion (CARA), or exponential utility.
This method has several advantages: It provides a simple interpretation of
effort as negative income, it is robust to differences in the wealth of the
agents, and it facilitates comparison with the recent consumption literature
(Caballero [1990]), which also uses CARA. Unfortunately, it makes comparisons
with the asset pricing literature, which uses constant relative risk aversion
(CRRA), more difficult. Given wealth levels, though, it is easy to calculate
relative risk aversion. As an additional check, I provide a few calculations
using CRRA.
More parameters come from recasting an example from Jensen and Murphy

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(p. 228). The CEO considers a project he privately values at $100,000, but
which costs the firm $10 million. This translates into the principal-agent
framework as follows: Let the set of acts be A=(0.001,0.1,0.2). To the
agent, taking action al is like paying $1,000, taking action az is like paying
$100,000, and taking action a3 is like paying $200,000. From the shareholder's
viewpoint, each action increases the probability of the good state, where
shareholder value is 700, by 0.025, so
I12(al)

=

IIz(az)

=

&(a3)

=

0.475
-0.5
0.525.

Taking action az instead of al thus results in (0.025)~(700-300), or a $10
million gain in expected shareholder value at a personal cost of $99,000. I
choose nine values for risk aversion, setting 7

=

0.125 to 1.125 by increments

of 0.125. Because 7 measures absolute risk aversion, it is not strictly
comparable to the more common measures of relative risk aversion, such as the
29 of Kandel and Stambaugh (1991) or the 2-3 of Friend and Blume (1977).
Using a wealth estimate from Jensen and Murphy (CEO-controlled company stock
holdings) of $8.8 million gives a relative risk aversion of 1.1 to 9.9.
Figure 1 presents the results for the base case, plotting the profit
share against risk aversion. Profit share is the increase in CEO compensation
divided by the increase in shareholder value between the good and the bad
state, or Wage(state2)-Wage(state1)/(700-300).

Table 1 reports the actual

numbers. The profit share fraction, when positive, varies from around 0.01 to
0.03, implying that CEOs get an extra $10 to $30 for a $1,000 increase in
shareholder value. Table 1 reports an overabundance of negative wages.
Realistically, negative compensation sometimes results, because stock holdings

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represent such a large share of total compensation. Requiring only positive
wages, while equally unrealistic, would dramatically alter the principal-agent
problem (Sappington [1983]).
For

-y

> 0.625, the profit share is zero, implying the agent takes the

easiest possible action. Income shows

no

response to shareholder value:

The

profit share fraction is 0. Everyone knew this held as y approached
infinity, but it is a definite surprise that a number less than 1 counts as
"close to infinity." For some plausible parameter values, the 0.00325 value
of Jensen and Murphy looks too sensitive. Perhaps the low profit share Jensen
and Murphy find in the data reflects an average including a few zeros.
The positive profit shares in table 1 underscore a related message of
Jensen, however. The response of executive pay to firm performance, though
slight, significantly increases the firm's value. A positive profit share
makes sense only if it induces the agent to work more, to choose a2 or a3
instead of al. In my example, this is a gain to shareholders of $10 million
or $20 million.

Because the principal must compensate the agent for the risk

involved, if the agent still takes the lowest action he gains nothing and the
principal loses. Furthermore, because the principal (shareholders) maximizes
net benefits, a less sensitive scheme (though cheaper) would induce the agent
to pick a lower action, at a substantial cost.
Do these results make sense? Is there any reason behind the particular
values shown in table l? One advantage of an explicit model is that we can
explore such questions and deepen our intuition about the problem.

In

general, the compensation contract represents a trade-off between insurance
and incentives. A risk-neutral agent would bear all of the risk and accept a
profit share of 1, but a risk-averse agent would naturally desire to shift

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some of the output risk to the risk-neutral principal. Using the model, we
can quantify both sides of the trade-off and understand what motivates the
principal and the agent.
The contracts in table 1 clearly share risk between the principal and
the agent. At a risk aversion of 0.125, wages in the good and bad state
differ by $4 million (four units in the table).

The agent would pay $365,000

to avoid this risk. To keep the agent at his reservation utility, the
principal must compensate him with a risk premium for accepting this
uncertainty. If the agent bore the full profit uncertainty (+$200 million),
he would demand a risk premium of $194 million. As Sappington ([1991], p. 49)
puts it, "To conserve on the risk premium she must award the agent for bearing
risk, the principal will choose to bear some risk herself."
Providing insurance to the agent creates its own problems, however. As
noted by Sappington (1991, pp. 49-50), "When he is effectively insured against
bad outcomes under the optimal contract, the agent will exert less effort to
avoid these bad outcomes." A closer look at the base-case contracts of table
1 shows that they do provide strong incentives to the agent despite relatively
low profit shares.
One reason behind the low profit share is the difference between
expected gains and realized gains. For a risk aversion of 0.125, the wage
difference of $4 million translates into a rather modest profit share 0.01, or
$10 per $1,000. But the CEO does not directly determine shareholder value; he
merely changes the odds.

Choosing a2 over al increases expected shareholder

value by $10 million; choosing a3 adds another $10 million.

From this

perspective, his compensation more closely matches his contribution.
From another perspective, the agent's pay also matches his contribution.

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By taking an action that improves expected shareholder value, he increases his
own expected value of pay by 0.025 x $4,000,000,or $100,000, his disutility
of effort from taking that action.

Robustness Checks
The base case directly confronts the theoretical challenge posed by
Jensen and Murphy, but as a single example, its results might be special or
unrepresentative. The next few tables and figures report on variations of the
base case. Changes include risk aversion and the agent's effect on profit,
number of acts, and reservation utility.
The first set varies both risk aversion and the agent's effect on the
probability of the gross profit level. The relation between the agent's
effort and the probability of success is given by another new parameter,
APROB. As APROB gets bigger, good actions increase the expected probability of
the good state by an increasing amount. In the three-act case,
I12(a,)

=

0.5-APROB

I12(a2)

=

0.5

U2(a3)

- 0.5+APROB.

In the next two tables, APROB varies from 0.00625 to 0.05625 by increments of
0.00625. It thus provides a range around the base-case value of 0.025.
Table 2 and figure 2 report the results. For high APROB and low risk
aversion, table 2 shows CEOs getting between $4 and $5 per $1,000, moving a
step closer to the $3.25 finding of Jensen and Murphy.
Figure 3 presents the results with a reservation wage of 0.25
($250,000). The share results hardly change, as befits CARA. Wage levels are
correspondingly lower, but are not reported.

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Figure 4 and table 3 report the results for a calculation using 11 acts
instead of the three used above, with similar results.
To some people, the relative risk aversion ( 7 times wealth) in these
examples may seem too high.

The next two figures address that problem.

Figure 5 looks at absolute risk aversion between 0.0025 and 0.0225.

Figure 6

shows profit share for very low levels of risk aversion. Even a billionaire
would have relative risk aversion below 0.00000001 with these preferences.
Even so, the pay-performance ratio stays close to 0.01, or $10 for every
$1,000. Low performance pay does not require high risk aversion.
In addition, figures 5 and 6 together emphasize the nonlinearity and
nonmonotonic relationship between risk aversion and profit share. They show
both a local minimum and a more extreme nonmonotonicity.

Extreme Cases
The principal-agent model predicts a wider range of behavior than the
results so far suggest. The profit share can approach one quite closely. It
can also approach zero and still retain some pay-performance sensitivity.
Figure 7 shows the results of changing A to (0.01,10,20), APROB to
0.025, and the risk-aversion range to 1 x 10-l2to 9 x 10-12. The figure shows
nonlinearity and a profit share around 0.999, or $999 per $1,000.
Figure 8 and Table 4 report the results for the CRRA case. This
calculation holds risk aversion constant at 9 and varies APROB from 0.05 to
0.45, in increments of 0.05. This means &(a3)

varies from 0.55 to 0.95.

The act set is A=(1,10,15), and the disutility of effort function is (1/20)a2.
The reservation wage is 0.25. These parameters result in a low profit share
fraction, which ranges from 0.000000033 to 0.0000003. This implies that

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executive compensation should increase between 0.003 and 0.03 cents per $1,000
of shareholder wealth.

In some cases, then, it takes little to motivate a

CEO.

V. Com~arisonwith Holmstrom and Mil~romResults
Holmstrom and Milgrom (1987), by making stronger assumptions, simplify
the calculations even more.

They take a strategy diametrically opposed to

that behind the two-state, finite-action case. They start by complicating the
model.

Essentially, the agent has so much freedom that only simple linear

rules provide the correct incentives.
The agent controls the drift rate of a stochastic process z over a time
period of one unit.
dz=pdt +dB.

The process z evolves according to the equation

The agent has a CARA utility, with quadratic disutility of

effort. The cost to the agent of controlling the drift is c(p)=(k/2)02.
Holmstrom and Milgrom show that the optimal compensation rule takes the form
a z

+ /I,with

the optimal pay-performance ratio of

Under this incentive scheme, the agent chooses a constant value of p. In
that sense, the problem reduces to a static setting.

I translate the Jensen and Murphy examples into this framework as
follows.

First, let the unit time period be one year. The controlled process

is shareholder wealth, whose standard deviation of 200 means a variance of
40,000. Assume a risk aversion y of one.

If a project worth $10,000,000 (10

units) to the shareholders decreases the utility of the agent by $100,000 (0.1

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units), this implies a k value of 0.018. Substituting these values into
equation (4), I obtain a pay-performance sensitivity of 0.00138, or $1.38 for
every $1,000.
More generally, the formula expressing profit share as a function of
risk aversion, keeping the disutility at 0.1 for 10, is 1/(1+800

7

e-7/1°).

Figure 9 plots profit share against risk aversion for 100 values of risk
aversion running from 0.025 to 2.5. Profit share runs from $47 per $1,000 of
shareholder value to 6 cents per $1,000.
The Holmstrom-Milgrom approach has less flexibility than that of
Grossman and Hart. It can neither use CRRA nor measure effort as negative
income, much less use the more general forms allowed by Al.

Controlling a

drift (but not variance) term is less general than changing outcome
probabilities. For these reasons, the Grossman-Hart approach seems the more
desirable one.
The Holmstrom-Milgrom approach, however, has an additional advantage
beyond computational simplicity. It can explain why the principal ignores
additional information about the agent's action. For example, shareholders
may have information about revenues and expenses, in addition to profits.
When the agent has some discretion over how to account for revenues and
expenses, this information should not influence his compensation. Note
further that even in the simplest case embodied in equation (4). a great deal
of information is ignored. Agent compensation depends only on a time
aggregate of total profits at year end, not on performance at each date.
At this level of analysis, there is no need to choose between the two
approaches. The two sets of results confirm each other. Both predict low
levels of pay-performance sensitivity, even for low levels of risk aversion.

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VI.

Conclusion
Owners and managers must decide how to share profits.

That decision

lies behind executive compensation, shareholding, the firm's debt-equity mix,
and even takeover policy.

Yet, the quantitative theoretical predictions about

that sharing are rare: a share of 1 for a risk-neutral agent, and a share of 0
for an infinitely risked agent. Where do real-world cases fit in?
This paper has used two methodologies, one due to Grossman and Hart and
one due to Holmstrom and Milgrom, to compute quantitative solutions. The
results should not be considered a test of principal-agent theory.
does not formally confront a specified hypothesis with data.

The paper

It should

rather be seen as an application of that theory.
A test is, in principle, possible with this methodology. Assuming a
distribution across parameters will produce a distribution across profit
shares and wages, and this distribution could be compared with estimated
values.

Empirically identifying the model requires restricting the joint

distribution of APROB, reservation utility, and risk aversion, about which I
have little intuition.

It seems better to leave explicit tests for future

work.
Still, I would like to claim that the results do provide information
about the correspondence between principal-agent theory and reality. Two
lessons emerge from the exercise:

(1) Low profit shares can occur with low

risk aversion, and (2) even low profit shares provide incentives and
substantially increase the value of the firm.

www.clevelandfed.org/research/workpaper/index.cfm

REFERENCES
Baker, George P., Michael C. Jensen, and Kevin J. Murphy. "Compensation and
Incentives: Practice vs. Theory," Journal of Finance, vol. 43, July 1988, pp.
593-613.
Byrne, John A. "It's So Hard to Keep Good Professors Nowadays," Business Week,
November 28, 1988, p. 92.
Caballero, Ricardo J. "Consumption Puzzles and Precautionary Savings," Journal of
Monetarv Economics, vol. 25, no. 1, January 1990, pp. 113-136.
Friend, Irwin, and Marshall E. Blume, "The Demand for Risky Assets," American
Economic Review, vol. 65, 1977, pp. 900-922.
Grossman, Sanford J., and Oliver D. Hart. "An Analysis of the Principal-Agent
Problem," Econometrica, vol. 51, no. 1, January 1983, pp. 7-45.
Holmstrom, Bengt, and Paul Milgrom. "Aggregation and Linearity in the Provision
of Intertemporal Incentives," Econometrica, vol. 55, no. 2, March 1987, pp. 303328.
Jensen, Michael C. "Eclipse of the Public Corporation," Harvard Business Review,
vol 67, September/October 1989, pp. 61-74.

, and Kevin J. Murphy. "Performance Pay and Top-Management Incentives,"
Journal of Political Economv, vol. 98, no. 2, April 1990, pp. 225-264.
Kandel, Shmuel, and Robert F. Stambaugh. "Asset Returns and Intertemporal
Preferences," Journal of Monetarv Economics, vol. 27, no. 1, February 1991, pp.
39-71.
Mirrlees, James. "An Exploration in the Theory of Optimum Income Taxation,"
Review of Economic Studies, vol. 38, 1971, pp. 171-208.

. "Notes on Welfare Economics, Information, and Uncertainty," in Essays
on Economic Behavior under Uncertaintv, ed. G. M. Balch, D. McFadden, and ShikYen Wu, North Holland, Amsterdam, 1974.
Sappington, David. "Limited Liability Contracts between Principal and Agent,"
Journal of Economic Theorv, vol. 29, 1983, pp. 1-21.

. "Incentives in Principal-AgentRelationships," Journal of Economic
Pers~ectives,vol. 5, no. 2, Spring 1991, pp. 45-66.
Sheshinski, Eytan. "Note on the Shape of the Optimum Income Tax Schedule,"
Journal of Public Economics, 1989, pp. 201-215.

www.clevelandfed.org/research/workpaper/index.cfm

Table 1
Wages and P r o f i t Shares

Risk
Aversion

Source:

-

Base Case

Waee
Bad State

Good State

Author's c a l c u l a t i o n s .

P r o f i t Share Fraction

N
N

Source:

Bad
State

Bad
State

Good
State

Good
State

Author's c a l c u l a t i o n s .

Probability
Gain

Risk Aversion

Probability
Gain

Risk Aversion

Bad
State

Bad
State

Good
State

Good
State

Panel A.

Good

Good

State
State
-

Bad

State
State
-

Bad

Wages

Wages and P r o f i t Shares

Table 2

Bad

Good

State
-

Bad

Good

State
-

State
State
-

Bad
State
-

Good
State
-

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o o o o o o m m w
0 0 0 0 0 0 m
3
. rml0h m

. . . . .

000000000
-00
n

.

.

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0 0 0 0 0 0 c n w w
0 0 0 0 0 .dl.,n
0 m m ~

. . . . .

000000000
-00
n

.

.

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Table 4
Wages and Profit Shares

-

CRRA Case

Wane
APROB

Source:

Bad State

Author's calculations.

Good State

Profit Share Fraction

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Figure 1
Profit Share vs. Risk Aversion-Base

Case

r i s k aversion
Source: Author's calculations.

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Figure 2
Profit Share vs. Agent Effect and Risk Aversion

Source: Author's calculations.

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Figure 3
Profit Share vs. Agent Effect and Risk Aversion-$250,000

Source: Author's calculations.

Reservation Wage

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Figure 4
Profit Share vs. Agent Effect and Risk Aversion-1 1-Act Case

Source: Author's calculations.

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Figure 5
Profit Share vs. Risk Aversion-Low

Risk Aversion

r i s k aversion
Source: Author's calculations.

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Figure 6
Profit Share vs. Risk Aversion-Extremely

2

3

4

Low Risk Aversion

5

6

risk aversion
Source: Author's calculations.

7

8
9
x 10-l2

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Figure 7
Profit Share vs. Risk Aversion-High

3

4

Profit Share

5

6

risk aversion
Source: Author's calculations.

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Figure 8
Profit Share vs. Agent Effect-CRRA

0.2

Case

0.3

gain in p r o b
Source: Author's calculations.

www.clevelandfed.org/research/workpaper/index.cfm

Fig~~re
9
Profit Sliare vs. Risk Aversion-Holmstrom-Milgrom

risk aversion
Source: Author's calculations.

Model