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Working Paper 8101
THE WELFARE IMPLICATIONS
OF ALTERNATIVE UNEMPLOYMENT INSURANCE PLANS

b y Mark S. Sniderman

Working papers o f t h e Federal Reserve Bank o f
Cleveland a r e p r e l i m i n a r y m a t e r i a l s , c i r c u l a t e d t o
s t i m u l a t e d i s c u s s i o n and c r i t i c a l comment. The views
expressed h e r e i n a r e t h o s e o f t h e a u t h o r and n o t
n e c e s s a r i l y t h o s e o f t h e Federal Reserve Bank o f
Cleveland o r of t h e Board o f Governors o f t h e Federal
Reserve System.

A p r i l 1981
R e p r i n t e d September 1982
Federal Reserve Bank of Cleveland

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THE WELFARE IMPLICATIONS O F
ALTERNATIVE UNEMPLOYMENT INSURANCE PLANS
by !?lark S. Sniderman*
A recent survey of and extension t o research on the topic of

unemployment insurance (UI) by Tope1 and Welch (1980) focuses on the
issue of UI financin g .'

In particular, following Becker (1972), they

a r e interested in the influence of the experience-rating provisions
of the American UI system on a f i r m ' s layoff policy.

They suggest

t h a t a more complete model of both firms and workers would be a
f r u i t f u l endeavor, and two e f f o r t s of t h i s type have been made by
Azariadis (1979) and Brown (1980).'

This paper investigates a pe-

numbral issue in the UI financing l i t e r a t u r e :

the relationship

between experience rating, public and private UI systems, and
individual welfare.

A public insurance system can never be perfectly

experience-rated i f the government desires people w i t h different
layoff probabilities to hold identical insurance policies.

A

corollary proposition i s t h a t a private insurance system, i f information i s perfect, would always feature fully- rated plans, b u t the
characteristics of these plans may f r u s t r a t e other public policy
transfer or maintenance).
l y a l l previous research points out the moral
he UI system, there has been l i t t l e attention
uced by government
introduces t h i s issue
irm i s tantamount to
the firm t o the vagaries of the business cycle.
*Mark Sniderman i s an economic advisor, Federal Reserve Bank of
Cleveland. The author wishes to thank Douglas Hough for helpful
comments.

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Firms may be willing t o bear t h i s exposure when UI i s part of an
impliclt labor contract with i t s employees, and employees likewise
may be willing to pay f o r the risk shifting through wage adjustments
(Azariadis (1975), Baily (1977a), (1977b). However, for some firms,
the degree of exposure necessary t o insure a l l workers legally may
contribute to insolvency.

Incomplete experience rating i s one

method of achieving risk-pooling among firms
posure of high-turnover firms.

and limits the ex-

Incomplete experience rating i s a

form of market intervention by government for the benefit of high
risk firms and employees.

Incomplete experience rating i s contro-

versial where UI i s concerned,in part because of the adverse incentives i t provides firms and employees.

A great deal i s known

about the distribution of the turnover risk ex ante than i s the case
in many other insurance markets.

For example, Munts and Asher (1980)

show that construction, manufacturing, and agriculture a r e most
likely t o be subsidized and t h a t trade, finance, insurance, and
real estate are most often the subsidizing industries.
Part I .

Basic Model

The basic model follows the one developed f o r competitive insurance markets by Rothschild and S t i g l i t z (1976). An individual has
an income of W i f he i s f u l l y employed f o r some period, and an income of W-d i f he suffers a layoff.3 The individual can insure himself against t h i s layoff by paying a premium a,I t o an insurance
company, in return for which a net benefit of a3 i s paid in the event

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of layoff.

The vector a = ( a l , a 2 ) denotes the insurance contract.

Preferences f o r income in the two s t a t e s of nature a r e given by the
the expected u t i l i t y function:

where U(.) describes preferences f o r money income, W1 = W
( n e t income), W2 = W
probability.

-

-

al,

d + a 2 ( n e t income), and p i s t h e layoff

All individuals a r e identical except f o r t h e i r layoff

p r o b a b i l i t i e s , and a l l a r e r i s k averse (U"

< 0).

Contracts a r e sold

by risk- neutral, expected-profit-maximizing insurance companies.
Mhen contract a i s sold t o an individual with layoff probability

p,

the contract i s worth:

t o the individual and,
(3

n(a,

P) =

(1 - p)al - P a2

t o the insurance company.
zero expected p r o f i t s .
insurance ( i.e.

,

Free entry and perfect competition require

In equilibrium, individuals have complete

they expect the same income whether l a i d off or

not) purchased a t a c t u a r i a l odds. 4

x
(1 -

Suppose a f r a c t i o n
firms and a fraction

of a l l individuals work f o r high turnover
A ) work f o r low-turnover firms.

If layoffs

w i t h i n firms o f each type a r e random, then individuals can be c l a s s i -

f i e d as high- and low-risk types purely on the basis of t h e i r employand low-, and average-risk probabilities
ment a f f i l i a t i ~ n . High-,
~

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a r e denoted by:
pH, pL ( p

H

> p

L

), and

d

= h p H +(1 - A )

p

L

.

Rothschild and S t i g l i t z (1976) demonstrate that in t h i s type of
market, with imperfect information, there cannot be an equilibrium
in which both groups of individuals purchase the same insurance
contract (pool ing equil i b r i urn) .6 They further establ i sh t h a t even
when high-and low-risk types purchase separate contracts, an equilibrium may not e x i s t (separating equilibrium). A diagram, which
will be used in various forms throughout the paper, c l a r i f i e s the
7
basic model (see Figure 1). The point E represents expected income
i n each of the two s t a t e s of the world. The EH l i n e has slope
H
(1 - p ) l o H ; i t represents a l l actuarially f a i r contracts f o r high-

risk individuals (or firms).

The EL l i n e has slope ( 1

and an analogous interpretation.

-

The slope of EF i s ( 1

p L )/p L

- pip).

Sol id 1ine indifference curves depict high-risk individuals and
dashed 1ine indifference curves depict low-risk individual s .
In contrast w i t h Rothschild and S t i g l i t z , I am interested in
examining an insurance market in which the accident (layoff) proba b i l i t i e s are known by customers, insurance companies, and the
government.

In the case of UI, t h i s point of view i s legitimate.

F i r s t , the moral hazard f o r the employee to extend his unemployment
spell i s not being considered here, so only the occurrence of a layoff i s important.

Furthermore, the employment and layoff policies

of f i r y s tend t o be related more t o industry type and size than t o

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other variables, and information of t h i s type i s easy t o obtain. 8
Fi nal l y, going concerns have a known track record regarding t u r n overs that result in UI benefits paid.

Future layoffs cannot be

perfectly predicted, of course, b u t relative layoff rates among firms
a r e likely to be f a i r l y constant over time.

Over short periods of

time, the actual layoff rates f o r high- and low-risk firms may d i f f e r
from p H and p L , b u t over more lengthy periods (such as several
years) the distributions of layoff rates are assumed t o have means
of p H and p L The variances of these firm layoff rates are important,

.

and they will be discussed more f u l l y in Part 11.
The two contracts a and 6 ( i n Figure 1 ) are the separating equilibrium contracts sold respectively to high- and low-risk firms by
private insurance companies.

Although both high- and low-risk

individuals are f u l l y insured, low-risk individuals pay less per
dollar of benefit received, and they receive larger benefits i n the
event of a layoff.

There i s evidence that private insurance companies,

i f they could have written unemployment insurance pol icies in the 1920s,
woul d
firm.

offered group plans with premiums varying by industry and
riables , pol i c i e s

r e also re

such as a and B could result.

Private insurers would not be confined

t o issuing only contracts a and B , b u t they would r e s t r i c t themselves
to policies on or "below" the EH and EL lines.

Free entry presumably

would guarantee that a l l private policies actually appear on the EH
and EL l i n e s , and that in f a c t policies a and B result.

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Part 11.

Government Intervention

Suppose the government would require t h a t the benefit payments
of insurance companies must be identical among a l l policyholders
whose conditional income i s represented by E in Figure 2 , regardless
of t h e i r layoff probability.
policy

+

Some insurance companies might s e l l

t o a l l individuals and earn zero-expected p r o f i t s .

Hig

r i s k individuals would be b e t t e r
would become worse off.

Companies p

find t h a t another company, s e l l i n g u
t o low-risk individuals ( a 2 =
business.

ividuals and

T ~ ) ,

The 4 policy i s viable

and low-risk types in the proport
separating equilibrium S = ( a ,
This descripti
issues associated w

T)

of A and ( I

-

A).

The

dominates the pooling e q u i l i b r
uminates some
e United States.

Various i n t e r e s t groups were interested in different goals; some
wanted high benefits, others wanted limited l i a b i l i t y , others wanted
one national plan.

Disagreement over the form of UI insurance t o be

established by s t a t e governments in the 1920s could be construed as
disagreement over whether S or 4 was the b e t t e r social policy.
Policies of type S, i t was argued, encouraged employers t o reduce
layoffs ( i n e f f e c t , pivoting the EH l i n e u p toward the EL l i n e ) .
Other s t a t e s argued f o r pooling plans l i k e 4 on the grounds t h a t S
10
did n o t represent t r u e insurance.

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The debate over whether plans l i k e S represent t r u e insurance
and risk pooling r e l a t e s to the d i v e r s i f i a b i l i t y of the unemployment
risk.

The Rothschi ld-Stigl i t z model applies t o diversifiable r i s k s ,

a broader class than the class of independent r i s k s . l1 Tope1 and
Welch concede t h a t

"...the primary force militating against the

provision of firm-financed UI i s probably the high correlation in
the timing of unemployed spells f o r workers. "I2 To the extent t h a t
layoffs are correlated among covered workers, "insurance" plans
merely serve the purpose of transferring the lending and borrowing
a c t i v i t i e s of employees t o t h e i r employers.13 Tope1 and Welch provide evidence that in the United States the uninsurable portion of
total risk i s so large as t o " strain the solvency of private UI
programs. "I4 The covariance of firm-layoff r a t e s over time and
with other firms thus i s crucial t o

1) the s i z e and composition

of the pool of f i m s required of a diversifiable UI plan, and
2) whether such a UI plan i s true insurance (guarantees stipulated
benefits) o r i s a reserve fund t h a t pays out until i t i s depleted. 15
The equilibrium plans S and 4 i n Figure 2 a r e both true insurance plans i f the d i v e r s i f i a b i l i t y of the layoff risks i s
sufficient to guarantee solvency of the insurer.
neither one may be viable.

The policies a and

different insurance companies.

T

In actual practice,
may be marketed by

Since information i s perfect, s e l f -

B u t the market f o r one of these policies
16
may be too t h i n to guarantee solvency f o r the insuring company.

selection i s not an issue.

Similarly,

@

may not prove t o be a solvent policy ex post; a firm

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can s e l l Q in the ex ante c o r r e c t (zero-expected p r o f i t ) r a t i o
between the two risk c l a s s e s and s t i l l have a d e f i c i e n t number ,of
policyholders (and/or d e f i c i e n t c a p i t a l ) t o guarantee solvency.
The d i v e r s i f i a b i l i t y of the layoff r i s k s i s , of course, not
related t o the government requirement t h a t a l l UI plans pay identical
bevefits t o a l l policyholders.
unregulated markets.

This problem would e x i s t in completely

However, i t i s unlikely t h a t s t a t e governments

would permit undercapitalized underwriters t o operate within t h e i r
borders .I7 Private insurers may perceive the 1imi t s of d i v e r s i f i c a t i o n , even where reinsurance i s possible, as preventing t h e i r
participation i n any UI market, even i f benefit payments a r e very
low.

However, governments could guarantee "thick" markets, f o r

example,by assigning a s u f f i c i e n t number of diverse policyholders
t o each insurer so t h a t the probability of inso!vency would be considerably reduced.

In the 1irni t , t h i s law-of-large-numbers approach

might iniuly a monopoly insurance system, public o r private.

A public

monoooly UI system provides governments with the opportunity t o s e t
Senef it 1eve1 s , tax r a t e s , and e l i gi bi 1i t y requi rements in accordance
w i t h other public goals.

the
-

compulsory UI system.

Governments may choose t o o f f e r S or

+

as

Theycould a l s o e l e c t t o earn negative-

expected p r o f i t s by t r a n s f e r r i n g income from general tax r e c e i p t s
t o UI r e c i p i e n t s .
The current UI program in the United States operates as a
t r a n s f e r system i n ways other than inter- industry t r a n s f e r s .

Covered

workers a r e subsidized by the general public when the UI system

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borrows from the U.S. Treasury.

Whether or not high-income workers

subsidize low-income workers i s not clear.18 Of course, any
deliberate transfer system of t h i s s o r t i s inconsistent with true
insurance principles ( i .e. , a perfectly experience-rated system). 19
I t i s possible t h a t high-and low-income individuals would be better
off under such an income-transfer program than i f there were no UI
a t all.
Consider the situation of two large groups of people, d i s t i n guished from one another by income class (see Figure 3 ) .

Assume

i n i t i a l l y that each income class has the same proportion of high- and
low-risk individuals.

The example shown in Figure 3 i s one in which

those i n the high-income group (E2 i n i t i a l point) have twice as
much income in each s t a t e of the world as those in the low-income
group ( E l i n i t i a l point).

Assume further t h a t the government s e t s

a UI benefit level equal to one-half of (W1
tracts m
shows that policies

ml

and

-

W2)

Then government-

e BIBl or B2B2.

m2,

Inspection

which meet the benefit criterion and

are pooling e q u i l i b r i a , benefit only the high-ri sk individuals of
each income clas

improve the welfare of a l l low-income in-

di vi dual s whi 1e

ing the benefit c r i t e r i o n , say through policy

T-,

being sold to both high- and low-risk, low-income individuals,
me individuals must subsidize the negative-expected-profit
20
forms.

Either a l l high-

r , on the B2Be l i n e , or they

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purchase a policy l i k e e , near the

line.

The

Y

policy respects

the proportional - benefit c r i t e r i o n b u t severely punishes the highincome, low-risk individuals.
lot

The

policy greatly improves t h e i r

8

b u t violates the proportional-benefit c r i t e r i o n .

policy, located in the area formed by Y,
s p i r i t of a compromise.

m2,

e , and

An intermediate

a2,

i s in the

The actual choice of a subsidy i s partly a

function of arithmetic (the number of high-income individuals in
the society) and partly of p o l i t i c s (which risk class among the highincome group i s rendered more worse o f f ) .

In the American UI system,

benefit replacement i s typically proportional to a ceiling income,
a t which point the benefit increases no further.

If the group of

high-income individuals contained a larger proportion of low-risk
individuals than the group of low-income individuals, i t might be
possible t o (1) s a t i s f y the proportional -benefi t rule f o r both income
groups and ( 2 ) subsidize expected losses of the low-income group
while not making anyone worse o f f .
the

p

This situation would a r i s e when

l i n e f o r high-income individuals in Figure 3 i s very close t o

the L2 line.

Then a policy l i k e

w

makes positive-expected p r o f i t s ,

i s on the B2B2 l i n e , and makes no high-income individuals worse off.
A

The expected u t i l i t y function ( V ) that underlies the argument
i l l u s t r a t e d in Figure 3 generates homothetic expansion paths ( i .e.,
the slopes of ULl a t El and UL2 a t Ep are equal).

The logarithmic

uti 1i t y function, which displays constant relative r i s k aversion of
unity, yields an expected u t i l i t y function w i t h a homothetic expansion path.

When the expansion paths are not homothetic, i t may

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be possible to improve the welfare of both high- and low-risk highincome individuals, while a t the same time subsidizing the low-income
individuals.

The situation i s i l l u s t r a t e d in Figure 4.

Low-income

individuals receive a policy l i k e II on the BIBl l i n e , while highincome individuals receive a policy l i k e

0,

which improves t h e i r

position relative to E2 (regardless of risk type).

Notice t h a t the

slope of UL1 a t El no longer equals the slope of UL2 a t E2.
Part 111.

Conclusion

A proper concern of s t a t e governments i s the solvency of UI

plans operating within s t a t e jurisdictions.

Perfectly experience-

rated private UI plans are likely t o structure premiums and indemn i t i e s differently than public UI plans, partly because public plans
are less concerned about solvency.

Public plans in principle can be

perfectly experience-rated, b u t such plans would entail different
costs per dollar of insurance f o r high- and low-risk individuals.
Though economically j u s t i f i a b l e , these differences may be d i f f i c u l t
to defend pol i t i c a l ly.

Yet, once governments attempt t o provide

"adequate" benef i t s , o r "proportional " benefits , perfect experience
rating must be replaced by some pooled-equilibria-contracting pattern.
A monopoly UI system based on pooling (imperfect experience rating)

forces some people t o purchase less than optimal insurance coverage,
while others may purchase more than i s optimal.

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FOOTNOTES:
1.

The authors a r e unconcerned with the relationship between UI
benefit payments and job search a c t i v i t y .

I ignore t h i s issue

as we1 1 .
2.

Azariadis (1970) provides an example of how a f u l l y experiencerated plan can support an employment level larger than i s
socially optimal ; f o r an unrated system, the benefit level can
be chosen t o yield the socially desirable employment level
(see pp. 18-22).

Brown's model shows t h a t severance pay and

labor mobility a r e important factors i n the f i r m ' s layoff
policy and the nature of the optimal contract.
In other words, layoff duration i s known with certainty.

The

employee moral hazard i s disregarded.
As a r e s u l t of equations 1 , 2 , and 3 , the following conditions
hold:

n(o,p) = 0

+

ap/ol = (1

-

p)/p

W2)

= slope of actuarial odds l i n e

PI =

(1 -

P)/P

when W1 = WE.

uals among firms causes no
problems as long a s X i s fixed.

6.

Equilibrium i s of the Cournot-Nash type:

no equilibrium contract

ected p r o f i t s , and there i s no non-equilibrium
contract t h a t earns a non-negative p r o f i t , i f offered.
7.

This diagram comes d i r e c t l y from Rothschild and S t i g l i t z (1976),
hough subsequent modifications do n o t .
i l i e n (1980) provides evidence that the range of average rehire
g manufacturing industries i s quite variable ( p . 28).

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FOOTNOTES (cont ' )
9.

James (1947) recounts the attempts of t h e Metropolitan Life
Insurance Co. t o obtain permission t o w r i t e UI p o l i c i e s from t h e
New York S t a t e Assembly.

In the Metropolitan plan benefits would

depend on wages, employment tenure, and unemployment duration.
See pp. 226-31.
10.

Under t h e Wisconsin plan, each employer's l i a b i l i t y was limited
t o the reserves s e t aside in a fund.
minimum b e n e f i t .
surance.

There was no guaranteed

This plan was decried a s not being t r u e in-

Some s t a t e s , such a s Ohio, believed t h a t minimum b e n e f i t s

could be guaranteed by pooling plans.

For a more general

description of t h e h i s t o r i c a l and l e g i s l a t i v e history of UI,
see Nelson (1969) and Haber and Murray (1966).
11.

Rothschild and S t i g l i t z (1976), p. 631, footnote 4.

12.

Tope1 and Welch (1980), p. 355.

13.

This i s l i k e l y t o be desirable from the employees' viewpoint,
because t h e firm has comparative advantages i n these practices.
Furthermore, firms can d i v e r s i f y more completely than employees.

14.
15.

Tope1 and Welch (1980), 7 . 356.
Suppfemental unemployment benefit funds i n the automobile and
s t e e l i n d u s t r i e s a r e examples of such reserve funds.

16.

The s t a t e of Michigan recently considered revoking the s e l f insurance s t a t u s of Chrysler Corporation i n t h e s t a t e workmen's
compensation program, because of the f i r m ' s potential insolvency.
See "Chrysler Must Buy Workers' Insurance, Says S t a t e of Michigan,"
Wall S t r e e t Journal, December 26, 1980, p.3.

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FOOTNOTES (con ' t )
17.

Again, the experience of Metropolitan Life i s instructive.

The

New York State Senate Insurance Committee was concerned that
Metropolitan Life policyholders would be exposed t o too much
risk i f the company were permitted to offer UI.

See James (1947),

pp. 226-31.

18.

There i s not much evidence on t h i s point.

The range of

benefit maxima in s t a t e UI programs (50 to 79 percent of average wages)
suggests t h a t an intra-program transfer e x i s t s .

B u t taxes are

collected on only the f i r s t $6,000 of each employees1 earnings,
suggesting a higher tax incidence on low-income workers.

Of

course, the tax exemption of UI benefits means that high-income
beneficiaries require fewer before-tax dollars than low-income
beneficiaries t o be on equal footing a f t e r tax.

Feldstein (1974)

reports that the distribution of benefits i s similar to the
distribution of income for the general population.

On t h i s

basis, he argues t h a t the poor do not benefit much from UI.
My interest i s only in transfers among covered workers.
19.

Practical matters, however, apart from an income -transfer
motive, might lead to an insurance system with the ex post
characteristic of income transfer.

These practical considera-

tions include employer and employee moral hazards and imply
coinsurance f o r certain groups of people.
20.

Assuming, of course, that the entire UI program i s &sisned to be
ac tuarial l y sound.

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REFERENCES
Azariadi s , Costas. (1975).

" Impl i c i t Contracts and Underemployment

E q u i l i b r i a ,"Journal of P o l i t i c a l Economy, vol . 8 3 , pp. 1182-1202.
"Impl i c i t Contracts and Related Topics:

Azariadis, Costas. (1979).

A Survey." Processed. University of Pennsylvania, Department of
Economics, CARESS Working Paper No. 79-17.
Baily, Martin Neil. (1977a).

"Unemployment Insurance a s Insurance f o r

Workers," I n d u s t r i a l and Labor Relations Review, vol. 30, pp. 495-504.
Baily, Martin Neil . (1977b).

"On t h e Theory of Layoffs and Unemployment ,"

Econometrica, vol. 45, pp. 1043-63.
Becker, Joseph M. (1972).

Experience Rating i n Unemployment Insurance :

An Experiment i n Competitive Socialism.

Baltimore and London:

Johns Hopkins University Press.
Brown, James N . (1980).

"How Close t o an Auction I s t h e Labor Market?

Employee Risk Aversion, Income Uncertainty, and Optimal Labor
Contracts."

Processed.

National Bureau of Economic Research

Working Paper No. 603.
Fel d s t e i n , Martin. (1974).

"Unemployment Compensation :

Incentives and D i s t r i b u t i o n a l Anomalies."

Adverse

National Tax J o u r n a l ,

vol. 27, pp. 231-244.
Haber , W
i 11iam, and Merri 1 Murray. (1966).
t h e American Economy.
James, Marquis. (1947).
Growth.

New York:

Homewood, 111.:

Unemployment Insurance in
Richard D. Irwin Co.

The Metropolitan Life:
Viking Press.

A Study in Business

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REFERENCES c o n ' t
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