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Working Paper 8712 IMPLICIT CONTRACTS, ON-THE-JOB SEARCH AND INVOLUNTARY UNEMPLOYMENT by Charles T. Carlstrom Charles T. Carlstrom is an economist at the Federal Reserve Bank of Cleveland 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 1987 Abstract This paper extends t h e i m p l i c i t c o n t r a c t s framework t o a l l o w f o r on - the - job search. I t i s shown t h a t i n v o l u n t a r y unemployment can a r i s e i n such a framework w i t h o u t p l a c i n g any a p r i o r i r e s t r i c t i o n s on e i t h e r wages o r severance payments. The model a l s o i m p l i e s t h a t firms w i l l p r a c t i c e a t w o - t i e r system o f a d j u s t i n g t h e i r l a b o r f o r c e . o u t s i d e j o b o f f e r s leave t h e f i r m . I n t h e f i r s t stage, workers who r e c e i v e The second stage c o n s i s t s o f f i r m s h i r i n g a d d i t i o n a l workers d u r i n g good s t a t e s o f n a t u r e , and l a y i n g o f f workers d u r i n g bad s t a t e s o f n a t u r e . Furthermore, d u r i n g "bad enough" s t a t e s o f n a t u r e , f i r m s w i l l o f f e r a severance payment o r bonus f o r those who want t o v o l u n t a r i l y leave, and then l a y o f f workers w i t h o u t o f f e r i n g a l a r g e enough severance payment t o compensate them f o r b e i n g unemployed. INTRODUCTION Traditional models of equilibrium unemployment have failed to explain why some unemployment might be involuntary. For example, sequential search models, such as Lucas and Prescott's (1974) paper, imply that workers wi 1 1 become unemployed when their expected present discounted value of future utility is greater when they are unemployed than employed. Another objection to the search model's explanation of unemployment is the assumption that unemployed search is more productive than employed search. This assumption has been frequently questioned and recent evidence suggests the opposite might be true. ' The purpose of this paper is to provide a consistent story of involuntary unemployment without placing any a priori restrictions on either wages or severance payments. While the existence of involuntary unemployment is by no means universally accepted, most economists accept it as a stylized fact of the labor market.' It therefore warrants an explanation within the traditional framework of equilibrium economics. This paper imbeds a simple model of on-the-job search in an implicit contracts framework. Implicit contracts provided one of the first equilibrium attempts to explain involuntary unemployment. In Azariadis' seminal work, involuntary unemployment results from three assumptions: 1) Workers are risk averse while firms are risk neutral. 2) Working is a 0 or 1 decision, that is, hours worked per worker is not a choice variable. 3 ) Firms cannot make severance payments to unemployed workers. Given these assumptions, involuntary unemployment results. Ex ante the optimal contract calls for workers t o become unemployed during certain states o f nature and t o consume the value of their leisure, thus truncating bad states of nature. Since workers are risk averse, however, and desire a constant consumption stream, it is not optimal to lower the wages of employed workers in order to induce them to leave. Similarly, by assumption, firms cannot make severance payments in order to induce workers to voluntarily leave. Another characteristic of Azariadis' model is that there is overemployment. That is, even though there is involuntary unemployment in the sense that laid-off workers are worse off than their employed counterparts, there is over-employment because there is more employment and less unemployment than would occur in a pure Walrasian market. Workers remain employed even though their marginal productivity of labor is less than their reservation wage. Both involuntary unemployment and overemployment result from the assumption that firms cannot make severance payments to laid-off workers. This inability to pay severance payments implies that firms will partially insure workers against the risk of being laid-off by remaining employed longer than they would in a pure Walrasian market. Once severance payments are allowed, unemployment becomes purely voluntary and there is production efficiency. The goal of this paper is to integrate a simple model of on-the-job search in an implicit contracts framework. This paper investigates the conditions under which involuntary unemployment will occur without placing any a priori restrictions on severance payments. Like Azariadis' model, an explanation of involuntary unemployment will necessitate their seeing overemployment. This is in contrast to Grossman and Hart who attempted to explain underemployment. That is, Grossman and Hart attempt to explain the ex post regret on the part of firms in the sense that they are laying off workers who ex post they would want to remain employed. However, all unemployment was voluntary. A recent paper by Oswald provides the first attempt to explain both involuntary unemployment and underemployment, but to do so he exogenously assumed that severance payments were zero. On the other hand, this paper attempts to explain involuntary unemployment, i.e. the ex post rqgret of workers in the sense that ex post they would rather remain employed with the firm given the prevai 1 i ng wage rate. In order to explain involuntary unemployment, it is promising to follow the lines of Kahn (1985). He showed that complete insurance is not possible (or that wages will not be independent of the state of the world) when a firm cannot monitor a worker's alternative wage offer. Arvan (1986) extended Kahn's analysis and suggested this might explain why involuntary layoffs occur. In Arvan's model, firms cannot insure against layoffs because of the need to promote on-the-job search. However, Arvan implicitly constrains the severance payment to laid-off workers to equal the severance payment offered those who voluntarily quit their jobs. It is this assumption that is crucial to explaining involuntary unemployment in his model. This paper is similar to both Kahn's and Arvan's in that it integrates the original implicit contract model with a simple model of on-the-job search. The structure of the model differs from theirs by assuming that on-the-job search may or may not result in a job offer, and by assuming that searching does not affect the resulting wage offer. If a worker receives a job offer, the present paper assumes the offer is exogenously given. These assumptions are not necessary and are meant to simp1 ify the analysis. To explain involuntary unemployment, no a priori restrictions wi 1 1 be placed on the structure of severance payments. The restrictions placed on severance payments result from the incentive compatibility constraints. However, the last section does assume that severance payments must be non-negative. The structure of the paper is as follows: Section one considers the symmetric information case when a firm can observe both a worker's search intensity and whether or not the worker receives a job offer. The optimal contract in this case implies complete insurance. Section two drops the assumption that a firm can observe a worker's search intensity, but assumes the firm can observe which workers receive job offers by making severance payments conditional on the worker accepting an offer. The section shows that the inability of a firm to observe a worker's search efforts is not sufficient to explain involuntary unemployment. However, the model results in incomplete risk-sharing because firms trade off their desire to provide incentives for on-the-job search and to insure workers against future wage changes. The optimal contract is also characterized by production efficiency for laid-off workers. However, workers who receive job offers are shown to leave more often than would occur in a Walrasian world, implying that identical workers (in terms of productivity) will leave the firm and commence working for the firm simultaneously. The third section investigates the .conditions necessary t o explain involuntary unemployment. It shows that when firms cannot observe both a worker's search efforts and whether or not a worker receives a job offer, the incentive compatible contract implies that laid-off workers will be better off than their employed counterparts. However, this result assumes that firms can tax departing workers. If this assumption is dropped, the optimal contract results in involuntary unemployment. This occurs in order t o provide the proper incentive in "bad enough" states of nature for job finders t o truthfully reveal that they received an offer. The section also discusses how t h e preceding a n a l y s i s would change i f a worker c o u l d save o r borrow f o r h i m s e l f r a t h e r than f i r m s a l s o a c t i n g as a bank f o r workers. The l a s t s e c t i o n concludes and discusses p o s s i b l e extensions f o r f u t u r e r e s e a r c h . I. THE MODEL WITH SYMMETRIC INFORMATION Consider an economy t h a t l a s t s f o r two p e r i o d s indexed by t = 1 , 2. Labor i s h i r e d i n t h e f i r s t p e r i o d where p r o d u c t i o n takes p l a c e a c c o r d i n g t o a deterministic production function, f ( N ) . P r o d u c t i o n i n t h e second p e r i o d i s s u b j e c t t o a random shock, 8, where t h e range o f 8 i s t h e c l o s e d i n t e r v a l CO, 8"l, w i t h d i s t r i b u t i o n f u n c t i o n s g(8) and G(B>, r e s p e c t i v e l y . model may be i n t e r p r e t e d i n a s e c t o r a l s h i f t s framework. The Workers search f o r a l t e r n a t e work i n t h e f i r s t p e r i o d i n case t h e demand f o r t h e i n d u s t r y ' s o u t p u t f a l l s s u b s t a n t i a l l y i n t h e second p e r i o d o r , a l t e r n a t i v e l y , i f t h e r e i s a bad shock t o p r o d u c t i o n i n t h e second p e r i o d . I n t h e f i r s t p e r i o d , workers choose t h e i r search e f f o r t , A, where X r e p r e s e n t s t h e p r o b a b i l i t y t h a t a worker w i l l r e c e i v e a j o b o f f e r . A worker's search i n t e n s i t y i s chosen i n t h e f i r s t p e r i o d b e f o r e t h e r e a l i z a t i o n o f t h e random shock t o f i r m p r o d u c t i o n i s r e a l i z e d . a f f e c t t h e p r o d u c t i v i t y o f a worker. Searching i s assumed n o t t o For s i m p l i c i t y , i t i s a l s o assumed t h a t s e a r c h i n g does n o t r e q u i r e any monetary c o s t , b u t r e q u i r e s i n s t e a d a " p s y c h i c " c o s t c(A>, which i s assumed n o t t o a f f e c t a w o r k e r ' s marginal u t i l i t y o f income. The assumption t h a t search e f f o r t e n t e r s s e p a r a b l y i n t h e w o r k e r ' s u t i l i t y f u n c t i o n i s n o t c r u c i a l ; i t i s meant t o a i d comparison w i t h o t h e r i m p l i c i t c o n t r a c t models. I f a worker r e c e i v e s a j o b o f f e r , i t i s assumed t o be for an exogenous amount, w ' . Workers a r e assumed n o t t o be a b l e t o a f f e c t t h i s wage o f f e r through searching. I t i s t e m p o r a r i l y assumed t h a t t h e f i r m cannot h i r e a d d i t i o n a l l a b o r i n t h e second p e r i o d . T h i s assumption w i l l l a t e r be dropped so t h a t a d d i t i o n a l l a b o r can be h i r e d i n p e r i o d two a t t h e market wage r a t e , w'. Firms compete f o r workers i n the f i r s t p e r i o d by o f f e r i n g an employment contract. C o m p e t i t i o n among f i r m s f o r workers i m p l i i e s t h a t t h e e q u i l i b r i u m c o n t r a c t w i l l be chosen t o maximize t h e expected u t i l i t y o f a r e p r e s e n t a t i v e worker s u b j e c t t o a z e r o e x p e c t e d - p r o f i t c o n d i t i o n f o r t h e f i r m . C o n t r a c t s c o n s i s t o f wages, severance payments, l a y - o f f p r o b a b i l i t i e s and search i n t e n s i t y . s 1 ( 8 ) , s,(8), A), That i s , a c o n t r a c t c o n s i s t s o f { w l , w,(e), where w l i s t h e f i r s t p e r i o d wage; w,(8> 1(8>, q(8), i s the second p e r i o d wage chosen a f t e r t h e r e a l i z a t i o n of 8; l ( 8 ) and q(8) a r e t h e r e s p e c t i v e s e p a r a t i o n p r o b a b i l i t i e s i n t h e second p e r i o d f o r workers who d i d n o t r e c e i v e a j o b o f f e r and d i d r e c e i v e a j o b o f f e r a f t e r t h e end o f t h e f i r s t p e r i o d ; s , (8) and s q ( 8 > a r e t h e severance payments ( o r t a x e s ) g i v e n t o ( o r a p p l i e d t o ) workers who d i d n o t r e c e i v e j o b o f f e r s and workers who d i d r e c e i v e j o b o f f e r s r e s p e c t i v e l y . For t h e f u l l i n f o r m a t i o n case considered below, one can t h i n k o f t h e f i r m as a l s o choosing t h e sear ch i n t e n s i t y o f workers, A. Assuming t h a t workers cannot save o r dissave ( t h i s assumption w i l l be dropped l a t e r ) , so t h a t t h e i r income i n every p e r i o d i s i d e n t i c a l t o t h e i r wage i n t h a t p e r i o d , t h e expected u t i 1i t y o f a r e p r e s e n t a t i v e worker e q u a l s : where B i s t h e r e s e r v a t i o n wage o f a worker, o r t h e income e q u i v a l e n t of a worker consuming h i s endowed l a b o r . I t i s a l s o assumed t h a t U " ( . > e q u i v a l e n t l y , t h a t workers a r e r i s k averse. < 0, -- o r The i n t u i t i o n behind t h e above equation i s as f o l l o w s : X ( l - q ( 8 > ) i s t h e p r o b a b i l i t y t h a t a worker r e c e i v e s a j o b o f f e r , b u t remain employed a t t h e f i r m e a r n i n g w,; Xq(9) i s t h e p r o b a b i l i t y t h a t a worker r e c e i v e s a j o b o f f e r and accepts i t , i n w h i c h case t h e worker earns w ' p l u s t h e severance payment s,; (l-X>(1-1(8)> is the p r o b a b i l i t y t h a t a worker does n o t f i n d o t h e r employment and i s n o t l a i d o f f , i n which case he earns w 2 ; (1-1) i s t h e p r o b a b i l i t y t h a t the worker does n o t r e c e i v e an o f f e r and i s subsequently l a i d o f f , i n which'case he e a r n s t h e v a l u e o f h i s l e i s u r e , B, and t h e severance payment s , ( 8 > . Assuming t h e f i r m i s r i s k n e u t r a l , i t has p r e f e r e n c e s g i v e n by The o p t i m a l employment- c o n t r a c t i s f o r t h e f i r m o r t h e p l a n n e r t o choose {wl, w2(8), s , ( 8 ) , s 1 ( 8 ) , q(8), 1(8), A, N) t o s o l v e : max E V ( w l , En(w w~(€J), s,(8), s l ( B ) , q(B), I ( @ ) , A) w 2 (81, s , ( 8 ) , s , (B), q(@), I(@), A , N) 2 0 The f i r s t - o r d e r c o n d i t i o n s f o r t h i s problem are: w ' when 8 > 8' va) 8f'([l-Xq(f3)1N) vb) 8f'([(l-l(8))(1-X)lN>=B = where 8 < 8 ' = > q(8)=1, when8<e1 0 < l ( 8 ) < 1 and 8 > 8' = > 1(8)=0, 0 < q(8) < 1 . where 1 (Ot)=O and q ( e t > = l and y are the Lagrangian associated w i t h t h e expected p r o f i t c o n s t r a i n t and y , = Ny. The s o l u t i o n t o t h i s problem i s s t r a i g h t f o r w a r d . Since there are no i n f o r m a t i o n a l asymmetries, the optimal c o n t r a c t i n v o l v e s both p e r f e c t r i s k sharing according t o Borch's r u l e and production e f f i c i e n c y . Workers a r e guaranteed the same income d u r i n g a l l s t a t e s o f the world, independent of both the s t a t e o f nature and whether o r n o t a worker receives a j o b o f f e r . Workers successful i n t h e i r j o b search subsidize those who were unsuccessful. Production e f f i c i e n c y i m p l i e s t h a t the f i r s t workers t o leave are those w i t h the b e s t o u t s i d e o p p o r t u n i t i e s , i . e . the workers who r e c e i v e o f f e r s . After a l l the workers who have found jobs leave, f i r m s must a d j u s t the l a b o r f o r c e by l a y i n g o f f workers. Firms l a y o f f workers u n t i l the marginal p r o d u c t i v i t y i s equal t o the r e s e r v a t i o n wage o f the marginal worker. Workers are assumed t o have non-market o p p o r t u n i t i e s t h a t g i v e the agent an income e q u i v a l e n t o f B. Firms then subsidize workers who a r e l a i d o f f by g i v i n g them a severance payment so t h a t the worker i s i n d i f f e r e n t between s t a y i n g w i t h the f i r m o r l e a v i n g the f i r m . Firms a l s o f o r c e workers t o supply the optimum amount o f search i n t e n s i t y g i v e n by v i i i ) . One can t h i n k o f wages being s e t equal t o z e r o when workers supply l e s s than the r e q u i r e d amount o f search e f f o r t . searching i s equal t o the marginal b e n e f i t o f searching. The marginal c o s t o f The marginal b e n e f i t o f searching i s the d i f f e r e n c e between what the worker w i l l earn i n an a l t e r n a t e job, w ' , and what he would produce i n the c u r r e n t job, 8 f 1 ( . ) . good s t a t e s o f nature (8 > 8 0 , t h i s d i f f e r e n c e i s zero from p r o d u c t i o n efficiency, w h i l e i n bad s t a t e s o f n a t u r e the d i f f e r e n c e i s w'-B. The In marginal b e n e f i t o f s e a r c h i n g i s t h u s t h e p r o b a b i l i t y t h a t workers a r e l a i d o f f , G ( B ' ) , m u l t i p l i e d by t h e v a l u e i n u t i l s o f e a r n i n g w ' versus B. Since the marginal cost o f searching i s i n u n i t s o f u t i l s t h i s q u a n t i t y i s m u l t i p l i e d by a w o r k e r ' s marginal u t i l i t y o f income. Not s u r p r i s i n g l y , t h e o p t i m a l c o n t r a c t w i t h f u l l i n f o r m a t i o n i m p l i e s complete insurance and, hence, w i t h asymmetric i n f o r m a t i o n i t would n o t p r o v i d e workers w i t h any i n c e n t i v e t o search. The n e x t s e c t i o n c o n s i d e r s t h e o p t i m a l c o n t r a c t when a f i r m cannot m o n i t o r a w o r k e r ' s search i n t e n s i t y and can choose t h e s e p a r a t i o n p r o b a b i l i t i e s o f workers, t h a t i s , t h e f i r m can t a x d e p a r t i n g workers. 11. Both o f these assumptions a r e maintained u n t i 1 s e c t i o n 3. IMPERFECT MONITORING I n t h i s s e c t i o n , i t i s assumed t h a t a w o r k e r ' s search i n t e n s i t y i s p r i v a t e i n f o r m a t i o n t o t h e worker. However, f i r m s can observe which workers r e c e i v e j o b s i n t h e second p e r i o d i n t h e f o l l o w i n g manner: severance payments can be made c o n d i t i o n a l on t h e worker a c c e p t i n g a j o b o f f e r . With asymmetric i n f o r m a t i o n , f i r m s choose t h e o p t i m a l c o n t r a c t on t h e assumption t h a t workers w i l l t h e n choose X t o maximize t h e i r u t i l i t y g i v e n t h i s c o n t r a c t . g i v e n a c o n t r a c t {w, , w, ( 8 > , s, ( 8 ) , s , (€11, q ( 8 ) , 1(8), N) workers w i l l choose t h e i r d e s i r e d search i n t e n s i t y , X* such t h a t : A* = X argmax EV(wl, w,(8), E C0,lI s q ( 8 ) , s , (81, q(8), I(@), 1) That i s , Replacing the above condition with the first-order condition for an agent's search effort yields the reaction function for workers. It gives how agents will choose X in response to the employment contract. This incentive compatibility constraint is appended to the planner's (or the firm's) problem in the previous section, so that the optimal contract is to choose {wl(B>, w2(8), sq(8), sr(8), q(f3), max EV(w,, w2(8), 1(6), A , N) in order to solve the following problem: s,(8), s ,(8),q(8), I(@), The first-order conditions for this problem are X) va) 8f1(El-Xq(8)IN) - w' = {U(wl+sq> - U(w,> - U'(w1+sq>[(w'+s,> - w21)/U'(w1+s,> vb) 8f1(C(1-l(e))(l-X)IN) where vi) = B when 8 > 8 ' when 8 < 8' l ( 8 ' ) = 0 and q ( 8 ' ) = 1. f l ( N > = w, Using va) and vb) t o s i m p l i f y ii) y i e l d s : ii a > U1(w,(8>) = iib) U'(w,(8>>, = when 8 < 8 ' . y , (1-1) ( 1-A-y2 1 when 8 > 8 ' y l ( 1-Xq(8) C1-(X+y, )q(8)1 I n bad s t a t e s of n a t u r e when l a y o f f s occur, 8 < 8 ' , we have complete insurance f o r l a i d - o f f workers, i . e . B + sl = Wr. Workers who r e c e i v e j o b o f f e r s are subsidized and earn more than those who do n o t f i n d o t h e r employment, i . e . w ' + s, > w,. t h e o u t s i d e wage o f f e r w ' . w ' i s l a r g e i t may be a t a x . The s i g n o f sq depends on t h e magnitude o f I f w ' i s small, i t w i l l always be a subsidy, w h i l e i f I n good s t a t e s o f the w o r l d where 8 > 8 ' , no workers a r e l a i d o f f , and t h e workers r e c e i v i n g j o b o f f e r s earn more t h a n those who d i d n o t f i n d a1 t e r n a t e employment. smaller with better states o f nature. However, t h i s d i f f e r e n t i a l g e t s This i m p l i e s t h e paradoxical r e s u l t t h a t the marginal p r o d u c t i v i t y o f l a b o r decreases w i t h b e t t e r s t a t e s o f n a t u r e when 8 > 8 ' . I n t h e l i m i t , when q(8) = 0 , and thus when no workers l e a v e t h e f i r m , workers w i l l earn equal wages i n b o t h t h e f i r s t p e r i o d and t h e second p e r i o d . I t should be noted t h a t t h i s s o l u t i o n i m p l i c i t l y assumes t h a t f i r m s have t h e power t o e i t h e r s u b s i d i z e o r t a x workers who leave. That i s , even though workers who f i n d a l t e r n a t e employment m i g h t earn more a t t h e i r new jobs, w' > WE, f i r m s a r e assumed t o be a b l e t o t a x them ( o r sabotage t h e i r f u t u r e j o b p r o s p e c t s ) t o p r e v e n t them from l e a v i n g , thus r e g u l a t i n g t h e number o f workers who leave t h e f i r m . Since workers respond o p t i m a l l y t o changes i n t h e c o n t r a c t o f f e r e d t o them, e q u a t i o n v i i > . s t a t e s t h a t a w o r k e r ' s search i n t e n s i t y w i l l be chosen so t h a t t h e change i n t h e marginal c o s t t o workers f r o m i n c r e a s i n g t h e i r search e f f o r t i s equal t o t h e marginal b e n e f i t (expressed i n u n i t s o f u t i l i t y ) t o t h e f i r m r e s u l t i n g f r o m workers i n c r e a s i n g t h e i r search e f f o r t . The m a r g i n a l b e n e f i t f r o m i n c r e a s i n g a w o r k e r ' s search i n t e n s i t y i s t h e d i f f e r e n c e between what t h e worker is p a i d , w2 , and t h e sum o f what he produces, 8 f ' ( . > , and t h e severance payment g i v e n t o d e p a r t i n g workers, s,(B). This implies the f a m i l i a r r e s u l t : t h a t t h e o p t i m a l c o n t r a c t w i l l s p e c i f y l e s s search e f f o r t t h a n t h e f u l l i n f o r m a t i o n c o n t r a c t when y r > 0 . That i s , 1 i s chosen such t h a t t h e marginal b e n e f i t t o i n c r e a s i n g search e f f o r t i s s t r i c t l y positive. The p r o o f t h a t y z i s s t r i c t l y p o s i t i v e f o l l o w s f r o m t h e f i r s t - order conditions. effort. I f y~ < 0 then workers would .not s u p p l y any search A s u f f i c i e n t c o n d i t i o n for an i n t e r i o r s o l u t i o n t o o c c u r i s t h a t ~ ' ( 0 =) 0, ~ ' ( 1 )= and w ' > 8, i . e . i t i s c o s t l e s s t o e x e r t a l i t t l e search e f f o r t and t h e r e i s a p o s i t i v e b e n e f i t t o searching, w h i l e t h e m a r g i n a l c o s t o f searching, so t h a t a j o b o f f e r i s c e r t a i n , i s s u f f i c i e n t l y c o s t l y s o t h e p r o b a b i l i t y a worker w i l l r e c e i v e an o f f e r i s l e s s t h a n one. N o t i c e , t h e r e i s p r o d u c t i o n e f f i c i e n c y when f i r m s l a y o f f workers. This i s n o t s u r p r i s i n g s i n c e t h e r e i s complete i n s u r a n c e f o r l a i d - o f f workers. When t h e marginal worker t o leave, however, i s a worker who has r e c e i v e d a j o b o f f e r , i . e . when no workers a r e l a i d o f f , t h e r e i s underemployment. who f i n d j o b s l e a v e more o f t e n t h a n i n a Walrasian market. Workers T h i s i s symmetric w i t h t h e r e s u l t i n A z a r i a d i s ' model t h a t t h e r e w i l l be overemployment when t h e r e i s i n v o l u n t a r y unemployment. The i n t u i t i o n behind t h e p r e s e n t r e s u l t i s t h a t on- the- margin f i r m s f i n d i t o p t i m a l t o p r o v i d e a d d i t i o n a l i n c e n t i v e f o r on- the- job search by a l l o w i n g workers t o earn more a f t e r t h e y f i n d a n o t h e r j o b , and a l s o b y a l l o w i n g them t o l e a v e more o f t e n than t h e y would i n t h e f u l l i n f o r m a t i o n case. From va), t h e amount p r o d u c t i o n d i f f e r s f r o m t h a t which would occur i n Walrasian market i s dependent on t h e c u r v a t u r e o f t h e u t i l i t y f u n c t i o n , o r how r i s k averse workers are. The more r i s k averse a r e workers, t h e g r e a t e r t h e need t o i n s u r e a w o r k e r ' s income. Because t h i s r e s u l t s i n l e s s search e f f o r t , t h e r e i s a g r e a t e r need t o p r o v i d e i n c e n t i v e s f o r on- the- job search by a l l o w i n g them t o leave more o f t e n than i n a w o r l d w i t h symmetric i n f o r m a t i o n . Given t h a t 8 f i ( . ) > w ' , t h e r e i s an i n c e n t i v e f o r workers who r e c e i v e job o f f e r s t o recontract with the f i r m . This i s n o t p o s s i b l e however, g i v e n t h e assumption t h a t f i r m s can o n l y observe which workers r e c e i v e d j o b o f f e r s a f t e r t h e o f f e r s were accepted. I n a d d i t i o n , t h e r e i s t h e i m p l i c i t assumption t h a t f i r m s cannot h i r e these workers back a f t e r t h e o f f e r has been accepted. T h i s i s meant t o i m p l y t h a t o f f e r s cannot be c o s t l e s s l y observed. If the f i r m c o u l d c o s t l e s s l y observe a w o r k e r ' s o f f e r , t h e r e would always be p r o d u c t i o n e f f i c i e n c y because f i r m s c o u l d b r i b e workers who f i n d j o b s t o c o n t i n u e employment b y o f f e r i n g them a h i g h e r wage r a t e , w ' . I f the marginal p r o d u c t i v i t y o f l a b o r i s g r e a t e r t h a n w ' , t h e n t h e f i r m has an i n c e n t i v e t o induce a worker who r e c e i v e d an o f f e r t o s t a y s i n c e t h e y can produce more a t t h e i r p r e s e n t j o b t h a n t h e y can a t an a l t e r n a t i v e j o b . Underemployment also results when 8 > 8' because firms, by assumption, cannot hire workers in the second period at the market wage rate, w ' . If additional labor can be hired, then an interesting result occurs. Workers will simultaneously leave the firm and accept employment with the firm. Since the marginal productivity of labor is greater than w ' , the firm will have an incentive to hire additional workers at w'. Although ex post this seems wasteful (although no mobility costs are built into the model), ex ante such behavior is necessary in order to provide workers with the proper incentives to search in the first period. To formalize this, assume that the firm can hire n(8) workers in the second period at a market wage rate of w ' . choose { w , (8), w2(8), s,(8), s , (B) , q(8), The optimal contract is then to 1(8), X , n(B), the following problem: max EV(w, , w,(8), s,(8), s ,(B), q(8), 1(8), A) s.t. E I I ( w , , ~,(8), sq(8), s.t. ~1(8),q(8), I(@), X , N) > 0 N) in order to solve The first-order conditions for this problem are vi) {U(w8+s,) - U(w2) - U'(w'+sq)[(wl+sq) - wZI}/U'(w'+sq) 8f1(C1-Xq(B)IN + n(8)) = w' for 8 > 8' vii) 8f1(C(1-l(B))(l-A)IN) = B for 8 < 8',where 1(8'>= for 8 > 8' 0 and q(8') Using v) and vi) to simplify i i ) yields: The results of this exercise are as follows: Workers who stay with the firm earn a wage rate, w,, which is independent of the state of the world. = 1. Workers who receive job offers receive a severance payment from the firms and will always accept outside job offers. When workers are laid off by the firm, 8 < 8', complete severance payments will be offered to them, thus there will be neither under nor overemployment, the marginal productivity of labor will be equal to B. No additional workers will be hired in these states of nature. When 8 > 8' ; however, so that no workers are being laid off, the firm will hire additional workers at a wage of w ' until production efficiency prevai 1 s. This contract implies a two-tier system for adjusting a firm's work force. Firms first offer a severance payment to workers who wish to voluntarily leave the firm. Every worker who has found another job will then accept this offer. In more complex models, one can think of the severance payment offered to departing workers as also consisting of possible early retirement benefits, etc.. After workers accept this offer, the firm then adjusts the labor force by laying off workers or hiring new workers until it reaches the desired level of employment. This sort of two-tier system does seem to have its counterpart in the world. The implication that workers, will be induced to quit while the firm hires new workers also seems to occur. Although the current analysis indicates that those who find jobs will always leave the firm, this result is because there are no adjustment costs incurred when hiring new workers. If there were adjustment costs (or firm specific human capital), not all of the workers who found jobs would leave the firm. It should be noted that since every worker who receives an outside job offer is allowed to accept the offer, the assumption that firms have the power to tax workers who leave is no longer necessary. Condition i i i ) assumes that the severance payment to workers who receive job offers might be negative. Dropping this assumption, however, would not change the nature of the results. The c o n d i t i o n f o r the optimum search i n t e n s i t y can be determined b y s u b s t i t u t i n g i i ) ,i v ) and v ) i n t o i x ) : Since YE, c l ' ( X ) , y, > 0 the optimal contract implies t h a t s1(8) > s , ( B > . The i n t u i t i o n behind t h i s r e s u l t i s s t r a i g h t f o r w a r d . c o n t r a c t when workers a r e r i s k n e u t r a l . Consider t h e o p t i m a l I n t h i s case, p r o d u c t i o n e f f i c i e n c y r e s u l t s and workers a r e p a i d t h e v a l u e o f t h e i r marginal p r o d u c t i v i t y i n e v e r y s t a t e o f the world. Assuming r i s k n e u t r a l i t y , workers would earn 0 , when 8 < e ' , and would earn w' when 8 > 8'. The f i r s t - p e r i o d wage would be chosen so t h a t f i r m s earn z e r o expected p r o f i t s . As workers become r i s k averse, f i r m s t r a d e o f f t h e i n c e n t i v e s o r p r o v i d i n g on- the- job search f o r i n s u r i n g workers a g a i n s t wage changes. F i r s t - p e r i o d wages would be reduced i n o r d e r t o reduce t h e d i s p e r s i o n i n second- period e a r n i n g s ; t h a t i s , s t ( @ ) > s, (8). Otherwise, i t would have been p r e f e r a b l e t o keep t h e c o n t r a c t t h a t r e s u l t e d when workers were r i s k n e u t r a l as i t a l s o p r o v i d e c t h e p r o p e r i n c e n t i v e s for on- the- job search. The above c o n t r a c t must be m o d i f i e d when t h e assumption t h a t f i r m s can observe which workers r e c e i v e j o b o f f e r s i s dropped, s i n c e t h e above c o n t r a c t w i l l n o t be i n c e n t i v e compatible. T h i s i s because t h e severance payment o f f e r e d t o workers who f i n d a l t e r n a t e employment i s l e s s t h a n t h e one o f f e r e d t o workers who a r e l a i d o f f (which j u s t compensates a worker f o r b e i n g unemployed); workers who d i d n o t r e c e i v e j o b o f f e r s w i l l never want t o p r e t e n d that they did receive a job offer. The opposite is not true, however, when a large fraction of the labor force is being laid off. Workers who found other jobs will wish to pretend they did not receive a job offer so they can be laid off and thereby collect the larger severance payment offered laid-off workers. The next section considers the optimal contract when the firm cannot observe a worker's search intensity, or whether or not a worker receives a job offer. 111. IMPERFECT MONITORING OF SEARCH EFFORTS The assumption that firms can hire additional labor in the second period will be maintained in this section, although this assumption is not necessary for the following results. If firms cannot monitor who receives job offers, then the optimal contract in the previous section is not incentive compatible. The incentive-compatible contract will be characterized by either involuntary unemployment or the opposite: involuntary employment, where unemployed workers are better off than their employed counterparts. The condition under which the first occurs, is if the firm cannot tax departing workers. The second result occurs if the firm has the power to tax departing workers, and thus the power to choose the separation rates for workers. T o solve for the optimal contract, when firms cannot observe which workers receive job offers, the following incentive compatibility constraint must be placed on the problem: The l e f t hand o f t h e above equation i s t h e expected u t i l i t y o f a worker if he admits he r e c e i v e d a j o b o f f e r , w h i l e t h e r i g h t - h a n d s i d e i s t h e expected u t i l i t y o f a worker i f he does n o t admit he r e c e i v e d a j o b o f f e r . case, when he i s n o t l a i d o f f he earns w, I n this < w ' , since t h e f i r m can r e s t r i c t his mobility. The o p t i m a l c o n t r a c t w i t h t h i s r e s t r i c t i o n w i l l choose {w, (8), w,(8), s,(8), max EV(w w2(8), s ( 8 ) , q ( 8 ) , I(@), A , N, n(8)) t o s o l v e : s,(8), s I (8), q(8), 1 ( 8 ) , 1) s. t. EII(w,, wZ(8), s q ( 8 ) , s l(B), q(8), 1 ( 8 ) , A, N) > 0 s.t. .f{l-q(8) )U(w2 ( 8 ) + q(8)U(w1+s, ( 8 ) ))g(8)d8 - J { ( 1 - - 1 ( 8 > > U ( ~ 2 ( 8 >- l(B)U(B+sl(B)))g(B)d8- ~'(1 =) 0 s.t. q(e)u(wl+s,(e)) 2 i ( e ) u ( w 8 + s 1 ( e ) ) + (l-I(e))u(w,(e)) s.t. n(8) 2 0 The f i r s t - o r d e r c o n d i t i o n s f o r t h i s problem are: vi) Ut(w2(8)){8f'(C(l-1(8)(1-X)1N)CU(B+sl(8)) - u(w~(8))l - y3(8)/(1-X-yl-y2)[U(B+~1(8)) B = U'(W'+S,(B))CB+S~(B)-W~(~)It - U(w1+s1(8))I where l ( 8 ' ) = 0, and q ( 8 ' ) = 1. Using va) and vb) t o s i m p l i f y ii) y i e l d s : The s o l u t i o n t o t h i s problem i s i d e n t i c a l t o t h a t g i v e n i n t h e p r e v i o u s s e c t i o n except f o r t h e i n c l u s i o n o f t h e c o s t a t e v a r i a b l e , y 3 ( 8 > , which becomes b i n d i n g i n "bad enough" s t a t e s o f n a t u r e . y3(8) > I t can be shown t h a t 0, i m p l y i n g t h a t i n s t a t e s o f n a t u r e where a l a r g e f r a c t i o n o f a g i v e n c o h o r t o f workers i s b e i n g l a i d o f f , t h e severance payment o f f e r e d t o d e p a r t i n g workers i n c r e a s e s , w h i l e t h e wage o f f e r e d t o t h e j o b s t a y e r s and t h e severance payment g i v e n t o l a i d - o f f workers decreases. s u f f i c i e n t t o e x p l a i n i n v o l u n t a r y unemployment. However, t h i s i s n o t I n f a c t , l a i d - o f f workers a r e b e t t e r o f f t h a n t h e i r employed c o u n t e r p a r t s . can t a x d e p a r t i n g w o r k e r s . T h i s o c c u r s because f i r m s I f a worker r e c e i v e s a j o b o f f e r and p r e t e n d s t h a t he d i d n o t f i n d o t h e r employment, t h e n t h e w o r k e r w i l l e a r n w,(8) i s not l a i d off. when he To see t h e i m p o r t a n c e of t h i s assumption, c o n s i d e r t h e case when f i r m s c a n n o t t a x d e p a r t i n g w o r k e r s . I n t h i s case, t h e w o r k e r can q u i t and e a r n w ' i n s t e a d o f s t a y i n g and e a r n i n g w,(8). The e f f e c t o f t h e i n c e n t i v e c o m p a t i b i l i t y c o n s t r a i n t w i l l be t o r e d u c e ~ ~ ( and 8 ) increase s,(8>. The severance payment t o l a i d - o f f w o r k e r s w i l l t h e n be l e s s t h a n n e c e s s a r y t o compensate them f o r b e i n g l a i d o f f . To m o d i f y t h e p r o b l e m so t h a t f i r m s c a n n o t choose t h e s e p a r a t i o n r a t e s o f w o r k e r s , t h e i n c e n t i v e c o m p a t i b i l i t y g i v e n e a r l i e r must be m o d i f i e d : The o p t i m a l c o n t r a c t w i 11 t h e n be t o choose { w , ( 8 ) , w 2 ( 8 ) , sl(8), yl(8), y 2 ( 8 ) , I(@), X, n ( 8 ) , N) t o s o l v e : max EV(w,, ~ ~ ( 8 s1q,( 8 ) , s I (8), q ( 8 ) , I(@), X) s,(8), To solve this problem, I will assume that w' is large enough so that states of the world will exist such that w, < w'. Otherwise, the results will be identical to that given.above and thus will not explain involuntary unemployment. The first-order conditions for this problem are: vii) - B) U'(w2(8)){8f'(C(1-1(B))(1-X)1N) = U1(wz(B))[w,(0) + U'(w,(B)> - (B+s1(0))1 - U"(B+sl(B)> - CU(wz(0)) - U(B+S~(B))I where l(0') = 0 and q(8') = 1. Using v) and vi) to simplify i i ) yields: i ia) U1(w2(8)> = y ,(1-1) for all 8. (1-1-yz-ys(8)) When no workers are laid off, the model produces a result similar to that in the previous section; all the workers who receive job offers will be permitted to leave. When workers are laid off, however, there is production efficiency except in certain bad states of nature where there is overemployment. This occurs because comparing iia) and iv) indicates that when a large fraction of the labor force is being laid off, there will be involuntary unemployment. The reason is that in order to get the job finders to truthfully reveal that they have found jobs, the severance payment to laid-off workers needs to be constrained. This differs from the result given earlier in this section, because when firms cannot tax workers only severance payments need to be constrained, rather than both severance payments and second-period wages. Job finders will then truthfully reveal when they receive offers. The condition for involuntary unemployment to exist seems particularly strong, since it requires a large fraction of the firm's labor force to be laid off. However, the condition does not seem unreasonable if the condition is reinterpreted as a plant closing, or where a large fraction of a given cohort of workers is laid off. The latter might arise in more complex models with firm-specific human capital which have a lay-off rule based on seniority. The model predicts that severance payments to both quits and lay offs will be state independent except during downturns. During severe downturns, the severance payment o r bonus o f f e r e d i n t h e f i r s t phase o f t h e l a b o r f o r c e adjustment w i l l a c t u a l l y i n c r e a s e . t r u t h f u l l y reveal t h e i r job o f f e r s . T h i s i s so t h a t workers who f i n d j o b s w i l l I n a d d i t i o n , d u r i n g these downturns t h e severance payments t o l a i d - o f f workers w i l l decrease so t h a t t h e y a r e involuntarily laid off. Because o f t h e c o m p l e x i t y of n o t a t i o n , I have assumed t h a t s, > 0, o r t h a t t h e n o n - n e g a t i v i t y c o n s t r a i n t on t h e severance payment o f f e r e d t o those who f i n d o u t s i d e o f f e r s i s n o t b i n d i n g . A l l o w i n g t h i s c o n s t r a i n t t o be b i n d i n g does n o t a f f e c t t h e r e s u l t s . A c r i t i c i s m o f t h e c u r r e n t model i s t h a t w h i l e i t extends A z a r i a d i s ' model, i t s t i l l p r e d i c t s t h a t severance payments should be p a i d t o l a i d - o f f workers. This i s i n l i g h t o f r e c e n t evidence by Oswald, t h a t r e l a t i v e l y few i n d u s t r i e s a c t u a l l y o f f e r some f o r m of severance payments, a l t h o u g h o v e r 50 p e r c e n t o f manufacturing i n d u s t r i e s do o f f e r such payments. I f t h i s model i s extended, however, so t h a t workers can save, i n s t e a d o f a l l savings and d i s s a v i n g s b e i n g p r o v i d e d by t h e f i r m , t h e p r e s e n t model w i l l p r e d i c t t h a t severance payments m i g h t n o t be as p r e v a l e n t as e a r l i e r p r e d i c t e d . Once savings a r e p e r m i t t e d one would n o t n e c e s s a r i l y p r e d i c t f i r m s t o save f o r workers. I f savings a r e p e r m i t t e d b e f o r e t h e r e a l i z a t i o n o f t h e shock t o f i r m p r o d u c t i o n i n t h e second p e r i o d , then workers would save i n t h e f i r s t p e r i o d an amount equal t o t h e severance payment o f f e r e d t o q u i t s i n t h e previous analysis. That i s , savings would be s , ( 8 > f o r 8 > 8 ' where 8' i s d e f i n e d t o be t h e c u t o f f a t which s, increases and s , decreases. The r e s u l t would be severance payments o f f e r e d o n l y t o workers who want t o v o l u n t a r i l y leave t h e f i r m d u r i n g bad shocks t o i n d u s t r y demand. Casual e m p i r i c i s m suggests t h a t indeed d u r i n g downturns f i r m s do o f f e r bonuses t o those who want t o v o l u n t a r i l y leave t h e f i r m . be v e r i f i e d by f u t u r e e m p i r i c a l work. However, t h i s p r e d i c t i o n c o u l d The model w i t h savings a l s o decreases t h e amount o f severance payments t h a t i s o f f e r e d t o l a i d - o f f workers. This m i g h t h e l p e x p l a i n t h e seeming l a c k o f severance payments t o workers i n most industries. Of course, a l l o w i n g workers t o save w i l l change t h e f i r s t o r d e r c o n d i t i o n s , since t h e r e would be another c o n s t r a i n t placed on t h e problem. However, t h i s c o n s t r a i n t would be independent o f 8 and thus would n o t a f f e c t t h e q u a l i t a t i v e r e s u l t s o f t h e paper. I V. CONCLUSIONS The goal o f t h i s paper was t o i n v e s t i g a t e t h e c o n d i t i o n s under which i n v o l u n t a r y unemployment can r e s u l t i n a standard i m p l i c i t c o n t r a c t s model t h a t i n c l u d e s t h e p o s s i b i l i t y o f on- the- job search. The r e s u l t s were encouraging; i t was shown t h a t under c e r t a i n c o n d i t i o n s i n v o l u n t a r y unemployment can e x i s t . The c o n d i t i o n s necessary t o achieve t h i s r e s u l t were: 1) Firms cannot observe a w o r k e r ' s search i n t e n s i t y , 2 ) Firms cannot m o n i t o r w h i c h workers r e c e i v e j o b o f f e r s , and 3 ) Firms cannot t a x d e p a r t i n g workers. The q u e s t i o n o f whether o r n o t t h e c o n d i t i o n s necessary t o e x p l a i n i n v o l u n t a r y unemployment occur o f t e n enough t o e x p l a i n t h e "observed" i n v o l u n t a r y unemployment cannot be answered. The paper a l s o showed t h a t f i r m s w i l l have a t w o - t i e r procedure f o r a d j u s t i n g i t s l a b o r f o r c e t o c u r r e n t economic conditions. I n t h e f i r s t round, a model w i t h savings i m p l i e s t h a t workers w i t h o u t s i d e o f f e r s would leave w i t h o u t t h e inducement of severance payments; i n t h e second round, t h e f i r m a d j u s t s i t s l a b o r f o r c e by e i t h e r l a y i n g o f f a d d i t i o n a l workers o r h i r i n g new workers. The model i m p l i e s t h a t workers w i l l leave t h e f i r m and new workers w i l l be h i r e d by t h e f i r m , a l t h o u g h a l l workers a r e assumed t o be e q u a l l y p r o d u c t i v e . This o c c u r s because, ex ante, f i r m s have t o o f f e r c o n t r a c t s , which g i v e s workers t h e necessary i n c e n t i v e s t o engage i n on- the- job search, which a l s o i m p l i e s s u b s i d i z i n g them when t h e y leave t h e f i r m . offers, However, ex p o s t , s i n c e f i r m s cannot observe who r e c e i v e s j o b they w i 11 f i n d i t p r o f i t a b l e t o h i r e new workers t o r e p l a c e those who quit. One frequent c r i t i c i s m o f t h e above a n a l y s i s i s t h a t i t i m p l i e s t h a t f i r m s a r e s u b s i d i z i n g workers t o engage i n more on- the- job search. Ex ante c o n t r a c t s w i l l be chosen so t h a t workers w i l l f i n d i t o p t i m a l t o engage i n such search a c t i v i t y , however, ex p o s t i t would n o t be s u r p r i s i n g t o t h i n k t h a t f i r m s a r e i n some sense a n t a g o n i s t i c t o such a c t i v i t y . Firms w i l l , of course, wish t h a t none o f t h e i r workers a r e s u c c e s s f u l i n t h e i r j o b search. S i m i l a r l y , another way o f t h i n k i n g about t h e problem i s t h a t f i r m s s i g n c o n t r a c t s t h a t reduce worker m o b i l i t y i n o r d e r t o p a r t i a l l y i n s u r e workers a g a i n s t income changes. T h i s paper showed why complete insurance t o l a i d - o f f workers would n o t be optimal, given the i n c e n t i v e c o m p a t i b i l i t y c o n s t r a i n t s . Additional empirical work i s necessary t o answer t h e q u e s t i o n o f whether t h e amount o f severance payments p r e d i c t e d by models, such as t h e p r e s e n t one, occurs i n the w o r l d . One reason t h e amount o f severance payments o f f e r e d by f i r m s m i g h t n o t be t h a t e x t e n s i v e , i s because o f state- mandated unemployment b e n e f i t s . Theory suggests t h a t t h e two a r e s u b s t i t u t e s ; thus, i n c r e a s e s i n s t a t e - p r o v i d e d unemployment i n s u r a n c e should decrease p r i v a t e severance payment programs. F u t u r e e m p i r i c a l work can be conducted t o see if p r i v a t e l y f i n a n c e d unemployment b e n e f i t s decrease w i t h increases i n s t a t e - p r o v i d e d unemployment insurance. Endnotes 1) For example, B l a u (1986) f i n d s t h a t f o r l e s s e f f o r t , employed s e a r c h e r s r e c e i v e more j o b o f f e r s t h a n unemployed j o b s e a r c h e r s . However, due t o unobserved d i f f e r e n c e s between employed and unemployed searchers, h i s d a t a remains p u r e l y s u g g e s t i v e . 2) For example, Lucas has argued: " I n v o l u n t a r y unemployment i s n o t a f a c t o r a phenomenon which i s t h e t a s k o f t h e o r i s t s t o e x p l a i n . I t i s , on t h e c o n t r a r y , a t h e o r e t i c a l c o n s t r u c t which Keynes i n t r o d u c e d i n t h e hopes i t would be h e l p f u l i n d i s c o v e r i n g an e x p l a n a t i o n f o r a genuine phenomenon: l a r g e - s c a l e f l u c t u a t i o n s i n t o t a l employment." 3) The problem i s a c t u a l l y t h e s o c i a l p l a n n e r ' s problem. The " d u a l " p r o b l e m where t h e f i r m maximizes i t s p r o f i t s s u b j e c t t o an i n d i v i d u a l r a t i o n a l i t y c o n s t r a i n t f o r t h e worker, does n o t a f f e c t t h e r e s u l t s . 4) To see t h i s , compare i i a ) w i t h i i i ) . Since U 1 ( w ' + s l ( B > > < U 1 ( B + s l ( B ) ) t h e n U 1 ( w 2 ) > U 1 ( B + s I ( B ) ) o r t h a t B + s l ( e ) > w,(B). References 1. 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