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Tilburg University Rubinstein auctions Chatterjee, K.; Dutta, B. Publication date: 1994 Link to publication in Tilburg University Research Portal Citation for published version (APA): Chatterjee, K., & Dutta, B. (1994). Rubinstein auctions: On competition for bargaining partners. (CentER Discussion Paper; Vol. 1994-57). CentER. General rights Copyright and moral rights for the publications made accessible in the public portal are retained by the authors and/or other copyright owners and it is a condition of accessing publications that users recognise and abide by the legal requirements associated with these rights. • Users may download and print one copy of any publication from the public portal for the purpose of private study or research. • You may not further distribute the material or use it for any profit-making activity or commercial gain • You may freely distribute the URL identifying the publication in the public portal Take down policy If you believe that this document breaches copyright please contact us providing details, and we will remove access to the work immediately and investigate your claim. Download date: 03. Sep. 2021

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Page 1: Tilburg University Rubinstein auctions Chatterjee, K.; Dutta, B. · Bhaskar Dutta Indian Statistical Institute, Dclhi Centre 7, S.J.S. Sansanwal Marg New Delhi, 110 016 India May

Tilburg University

Rubinstein auctions

Chatterjee, K.; Dutta, B.

Publication date:1994

Link to publication in Tilburg University Research Portal

Citation for published version (APA):Chatterjee, K., & Dutta, B. (1994). Rubinstein auctions: On competition for bargaining partners. (CentERDiscussion Paper; Vol. 1994-57). CentER.

General rightsCopyright and moral rights for the publications made accessible in the public portal are retained by the authors and/or other copyright ownersand it is a condition of accessing publications that users recognise and abide by the legal requirements associated with these rights.

• Users may download and print one copy of any publication from the public portal for the purpose of private study or research. • You may not further distribute the material or use it for any profit-making activity or commercial gain • You may freely distribute the URL identifying the publication in the public portal

Take down policyIf you believe that this document breaches copyright please contact us providing details, and we will remove access to the work immediatelyand investigate your claim.

Download date: 03. Sep. 2021

Page 2: Tilburg University Rubinstein auctions Chatterjee, K.; Dutta, B. · Bhaskar Dutta Indian Statistical Institute, Dclhi Centre 7, S.J.S. Sansanwal Marg New Delhi, 110 016 India May

~~~Z Discussion8414 for a er1994 iomic ResearchNR.

IIIIIIIIIIAI~INIIINNII~I N~I~ilullpl

Page 3: Tilburg University Rubinstein auctions Chatterjee, K.; Dutta, B. · Bhaskar Dutta Indian Statistical Institute, Dclhi Centre 7, S.J.S. Sansanwal Marg New Delhi, 110 016 India May

Centerfor

Economic Research

Óklyr J ~~'. .,

No. 9457

RUBINSTEIN AUCTIONS: ONCOMPETITION FOR BARGAINING

PARTNERS

by Kalyan Chatterjeeand Bhaskar Dutta

August 1994

G~,i~t C E-~ ~~ ~t S!~.~ ~~Ct ~ ~a ,, ,; ~

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ISSN 0924-7815

Page 4: Tilburg University Rubinstein auctions Chatterjee, K.; Dutta, B. · Bhaskar Dutta Indian Statistical Institute, Dclhi Centre 7, S.J.S. Sansanwal Marg New Delhi, 110 016 India May

RUBINSTEIN AUCTIONS: ON

COMPETITION FOR BARGAINING

PARNERS~`

ICalyan Chatterjeet

The Pennsylvania State University

University Park, PA 16802, USA

and

Bhaskar Dutta

Indian Statistical Institute, Dclhi Centre

7, S.J.S. Sansanwal Marg

New Delhi, 110 016 India

May 1994

'We wiah to thank the Penn State Center for Fieaearch in Conflict and Negotiation, the Center Cor

Economic Reaearch at Tilburg, the lndian Statiatical Inatitute and St. John's College, Cambridge, for

hoapitality during different phasea of the work on thie paper. We are also grateful to tlelmut Beeter for

useful commenta.

tTo whom correapondence ahould be addreased.

Page 5: Tilburg University Rubinstein auctions Chatterjee, K.; Dutta, B. · Bhaskar Dutta Indian Statistical Institute, Dclhi Centre 7, S.J.S. Sansanwal Marg New Delhi, 110 016 India May

1

1 Introduction

In this paper, we investigate the propertiea of some trading processea (extensive forms)

in a small market with competition on both sides. We focus on a simple model which

consists of two identical sellera, each with one unit of an indivisible good, and two buyers

with dijjerent valuations for the item. We consider three variants of an extensive form

where agents on one side of the market, say buyers, make offers aimultaneously, while

sellers respond simultaneously by either accepting or rejecting offera. Each offeror is

allowed only one offer per period, while a responder can accept at most one offer. An

acceptance means that the matched pair leaves the market. Unmatched pair(s) move

on to the next period and interchange roles of offeror and responder, payoffs being

discounted by a common discount factor. The three varianta differe in terms of the

nature of the offer and in the stnrcture of information. Details are deacribed in the next

section.

Our procedures have the following advantages. First, a player chooses whom he or

she will be matched with, rather than going through a random matching procedure more

appropriate for large, anonymous markets (as, for example, in Gale (1986) and Rubin-

stein and Wolinsky (1985)). Second, there is a minimal amount of order dependence

since of[ers and responses are made simultaneously. Third, price offera either precede

matching or are part of the same move, so a match has no rlacking inn effect. Fourth,

the procedure becomes a Rubinstein (1982) bargaining model with one seller and one

buyer, and essentially an auction with one seller and two buyers. Our generalization

therefore has some of the characteristics of both bidding and bargaining, as most real

rnarkets do.

We use this model to examine issues that have some point of contact with the lit-

eratures on bilateral bargaining with outside options, with matching and with general

coalitional bargaining. The main issue is the effect of competition for bargaining part-

ners on the price (or prices) that prevail in "thin~ markets, as well as how the matches

themselves are simultaneously determined. The matching literature (see Roth and So-

tomayor (1990) and Shubik (1982), the latter for the „assignment gamer that describes

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2

a situation very similar to ours) has concentrated primarily on co-operative notions of

stability like the core, without discussing how the matches get made non-rooperatively.

We investigate this question, albeit in a simple version of the game. The extensive work

on outside options or on bargaining in market contexts (see Binmore (1985), Hendon

and Tranaes (1991), Rubinstein and Wolinsky (1990), Shaked (1987) and the references

in Osborne and Rubinstein (1990)) has either looked at exogenous random matching of

agents or exogenously given outside options or extensive forms that impose an order of

proposers or responders. Many of these papers have dealt with one seller and two buyers,

though not in the auction-like setting of this paper.

The work of Ilendon and Tranaes (1991), for example, considers the case of a single

seller of valuation zero and two buyers B~ and BZ with valuations, v-~ 1 1 vz 1 z.

( We also make this assumption on the valuations.) In their paper, the seller is randomly

matched with one of the buyers, and, given the match, a random proposer is selected.

Rejection of a proposal leads back to another random match. Hendon and Tranaes

sl~ow that a stationary pure strategy equilibrium does not exist and that there is delay

(no immediate agreement) if the seller is matched initially with the low value buyer.

This occurs because there is a positive probability of ineeting the high value buyer in

the next period. However, if we consider our extensive [orm with one seller and two

buyers, these results do not appear. The seller offers E31 a price v~(1 - ó) } ëv2 (where

ó is the discount factor) and this is accepted. If the buyers make offers, both offer v~

and the seller accepts the high value buyer's offer. The possible delay in Hendon and

Tranaes is a function of their random matching process. With two identical sellers and

two heterogenous buyers, however, delay arises in our model without random matching.

Thus our model is qualitatively different from models like Hendon and Tranaes.

There have recently been several papers on non-cooperative theories of coalitional

bargaining. In Chatterjee, Dutta, Ray and Sengupta (1993), a sequential offer-extensive

(orm is analyzed and examples given of equilibira thaL fail to be in the core (as well

as conditions under which a specific allocation in the core will result). Bennett and

van Damme (1991) and Perry and Reny (1994) have pointed out that competition for

partners or undercutting of offers is ruled out in the sequential offers structure. This

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s

paper, by looking at simultaneous offers, allows undercutting, though we do (unlike Perry

and Reny) have a time zero at which the game begins. (Roth (1984) offers empirical

evidence for the assumption of a starting data in a matching market.) This model

therefore addresses issues relating to order dependence, undercutting and the core. '

'I'he results we obtain are somewhat surprising. In all the variants that we consider

here, either there is no purc strategy subgame perfect equilibrium or such equilibria

exhibit delay in reaching agroement ~, thua ensuring that an efficient outcome is not

obtained. It is worth emphasizing that typically simultaneous move games are charac-

terized by "lots" of equilibria, and that the "delay" result is not due to any imperïect

information.

The intuition behind these results is as follows. If both agrcements take place in the

same period, there is a tension between two forces on the price. The fact that a single

rejection will generate a"Rubinstein barganing subgame" leads to pressure on the prices

to diverge towards the two bargaining solutions. However, the simultaneity of offers

leads to competition and, therefore, undercutting or overbidding. This tends to push

prices towards a value that is irnmune to undercutting. This tension cannot be resolved

if two agreemeuts are to occur in the same period.

We also characterize the unique mixed strategy equilibrium that satisfies the property

that a response decision depends only on the offer received by the particular responder.

This equilibrium turns out to be intuitively more appealing.

In Section 2, we describe the trading processes in greater detail. Sections 3-5 contain

the main results.

2 Three 1ï~ading Processes

The situation we model is the following. Two identical sellers Sl and Sz each own 1

unit of an indivisible good. For simplicity, we assume that both sellers have the same

reservation value of zero for the good. There are also two buyers B~ and Bz, both of

~See also Moldavanu and Winter (1992).

~This is not quite accurate. See Propoeition 2 and Remark 1.

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4

whom demand 1 unit each of the commodity. The buyers' valuations are v~ and vz

respectively, with v~ 7 v~ ~ ~~ 0. Valuations are common knowledge.

The price(s) at which the good is exchanged if trade takes place is determined by

bargaining amongst the agents. In this paper, we describe three alternative bargaining

procedures. We call the first two the puólic offers, and targetted offers models, while the

third is the "telephone bargaining" model of Binmore ( 1984).

First, we describe the public offers model. In each period t E{0,1, 2, ...}, agents (say,

buyers) on one side of the market simultaneously announce a price p; at which they aze

willing to buy one unit. of the good. The two sellers then respond ( again simultaneously)

to the price offers. A response is either acceptance of one offer or rejection of both

offers. Ií both sellers accept B;'s offer of p;, then the two sellers are matched with equal

probability with B;. Both pairs are matched if the two sellers accept offers from different

buyers. Matched pair(s) leave the market with the good being exchanged at the agreed

price offer.

If some pair(s) remain unmatched at the end of period t, then in period ( t t 1), the

game is repeatcd with sellers making price offers and buyers responding to these offers,

agents on both sides of the market moving simultaneously as in period t. This procedure

is repeated so long as some pair remains in the market. All agents have a common

discount factor b E (0,1).

The tai~getted offers model is very similar. The only difference is that unlike in the

public offers model, an o,(íer consists of a price p and an agent on the other side of the

market. Thus, when buyers make offers, B; names a price p; along with a seller S~ with

whom B; wants to trade. And only seller S~ can accept or reject the offer of price p;

from B;. Also, even if two offers are received by a particular agent, the agent can accept

at most one offer. As in the public offers model, matched pair(s) leave the market, while

unmatchecl pair(s) continue the bargaining process with buyers and sellers interchanging

roles of offerors and responders.

In the targetted offers model, all offers are T heard" by both responders. Thus, even

if (say) B; makes an ofI'er to S; and B~ makes an offer to S„ S; and S~ are aware of both

offers. So, in principle, S;'s response decision can also depend on the ofíer received by

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5

S~. The telephone bargaining model is a variant of the targetted offers model in which

ofícrs are "transmitted" through telephone calls. In other words, if B; makes an offer

to S; and B~ to S„ then S; is unaware of the offer received by S~ and conversely. This

implies that response decisions can only depend on the offer(s) received by oneself.

Clearly, the bargaining processes described above can all be viewed as natural gener-

alizations of the alternating offers model of Rubinstein ( 1982). Our purpose is to analyse

the subgame perfect eyuilibria of these processes for "highT discount factors. In Section

3 and 4, we focus on pure strntegy equilibria of the public offers and targetted offers

modcls respectively. We show that there cannot be any pure strategy equilibrium in

the public offers model when buyers make offers. In the targetted offers model, all pure

strategy eyuilibria must involve delay, that is, in any period t, only one pair is matched

in equilibrium. Moreover, the pure strategy equilibria o( the targetted offers model can

ouly be sustained by rc~sponse decisions which depend on the offer received by the other

agent. This implies that there is no pure strategy equilibrium in the telephone bargaining

model. This prompts us to look at mixed-strategy equilibria in the telephone bargaining

model. In Section 6, we show that there is a unique mixed-strategy equilibrium in the

model.

In the remainder of this section, we will prove some preliminary results which will be

useful in the analysis of pure strategy equilibria in both the public offers and targetted

offers models.

Henceforth, we will denote by S-games ( B-games) the (sub)games in which sellers

(respectively buyers) make offers. Payoffs will be represented by R(B;), R(S~), etc. Thus,

ií one unit of the good is exchanged in period t between B; and S~ at price p, then

R(B;) - ó`(v; - p) and R(S~) - b`p.

First, we note that equilibrium cannot entail bargaining forever. For, if it did, an

o(Feror, B; say, could offer a price p which if accepted by either seller would give positive

payoffs to both B; and a seller. So, B;'s offer must be rejected by both sellers in the

public of['ers model and by a particular seller, say S„ in the targetted offers model. In

the former case, both sellers must have positive continuation payoffs in order to sustain

rejection of B;'s offer. But, this in turn is possible only if B; also has positive payoff,

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6

and hence B; is better off deviating from an offer that leads to bargaining forever (with

a zero payo(f). In the targetted offers model, if S~ rejects p from B;, it is because S~

has an agreement with B~ (say) that gives S~ a larger positive payoff. But, once one

agrc.jement occurs, B; and S; are in a Rubinstein game with positie payoffs. Again, B; ia

better o(f deviating from the offer leading to bargaining forever.

If an equilibrium exists therefore, it must consist of two agreements, either both in

period t or in periods (t,t t 1). Also, note that if only one pair reachea agreement

in pcriod t, then the remaining pair will be engaged in a Rubinstein alternating offers

subgame.

In checking candidate equilibria in Sections 3 and 4, we will often nc~d to consider

the case where a deviation írom his or her equilibrium strategy by one proposer leads

to both responders rejecting the offers. For example, let (sl,sz) be an equilibrium seller

payoff vector in the B-garne, with sl J sz. Then, if B; has a profitable deviation to

s~ -} e, both sellers must reject to sustain the equilibrium. Therefore, there exists an

equilibrium payoff vector (sl,sz) such that sl G óksi and s2 G óksz, where k is a time

index.

Lemma 0 Referring to the notation above, iJ (s„sz) is a B-game equilibrium with

strictly positive payoffs, there must be an S-game equilibrium payoff vector that also

sustains (s~,sZ) in the sense aóove.

Proof: Suppose not. Then, there is no S-game equilibrium payoff for sellers such that

s; C óm; for i- 1,2. However, there exists (9~,9~) in the B-game (by assumption)

such that s; G ó~s,. The pair (si,s~) must be an equilibrium payoff vector, and must

tlierefore itself be sustainable in the subgame caused by a deviating proposer and two

rejections. Since by irypothesis no S-game equilibrium sustans this, there is a B-game

seller payoff vector (s~,s2) such that s; G êZS;' for i- 1,2. But, we can repeat this

reasoning indefinitely, leading to a contradiction since seller payoffs cannot exceed vr.

Therefore, the original hypothesis is false. ~

Of course, the buyers' cases will be analogous.

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7

3 The Public Ofiers Model

In this section, we focus attention on the public oífers model. The main result (Propo-

sition 1) ahows that therc is no pure strategy equilibrium in the B-game. There is,

however, an equilibrium in which both sellers charge the same price and both buyers

accept this price. This is in the core of the game. However, we point out later on that

ttiis equilibrium is not robust since even a small amount of seller heterogeneity destroys

this equilibrium. -

A couple of lemmas precede the main propositions.

Lemma 1 In the public offers model, the candidate equíliórium payoff vectors oj sellers

in the S-game are described by the jollowing:

Ía) (si,sx) ~ [(rá ' (~á~

rb~ (sr,sx) ~ [(~~'id'(it ) 1

ici (sr,sx) - [Pr, (ártá)~ , where Pr ~ ~r~~.

(d) (91,92) - [Px, (áájl , where Px ? liá .

Proof: Suppose both pairs are matched in the S-game. Then, B; can by rejecting the

offers precipitate a Rubinstein subgame. This gives B; a payoff of 1}6 in the next period.

Flence, R(B;) ? ~~b, so that P, C rtb. This establishes (a).

If both buyers accept an offer P írom the same seller S;, then Bx has (expected) payoff

R(Bx) - z[(vx - p) t~]. Rejection of both offers gives Bx a payoff of ~. Hence,

p G rs. Also, seller S~(j ~ i) is matched with either buyer with equal probability in a

Rubinstein subgame. This gives the seller a payofi of z a~~~~b~ . This proves (b).

Suppose now that B; rejects óoth offers while B~ accepts p~ from S~. Then,

R(B;) -~i-b, whereas acceptance of p~ would have given B; an expected payoff of

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8

z[(v; - p;) } t1s~. So, tá ? v; - P; to sustain rejection of p; as an equilibrium. Also,

the wuuatchcd seller S; gets 1}6. '1'hese yield (c) aud (d).

Lemma 2 !n ller publir o,(jers niodcl, lhe candidalc equilib~ium payolj vcclonc of buyers

in the B-garne are described 6y the jollowing.

(a~ (6,, ~) s [~,á, ~,~;1z

(bJ (b;, 6;) G[v; - P,, ttó ~ jor i,j- 1,2 where

a~(cJ (b;, 6;) -[v; - P;, lóá~] for i, j - 1,2 where P; C~ta.

Proof: 'I'he proof of (a) is analogous to that o[ Lemrna 1(a), with the upper bounds on

buycr payofCs followiug from the scllers' payolCs iu respcctive Rubinstcin subgames.

Suppose now that both selle~rs accept P, from B; in equilibrium. Then, each seller

has expected payoff of R(S;) - z[P; -~ 1á~1 . Rejection of both offers gives either seller

a payoff of ~~6~.Hence, p; L~~ó~. Also, B; is in a Rubinstein subgame with the seller

making the first offer. This establishes (b).

Case (c) corresponds to the case where one seller accepts P; from B;, while the other

seller rejects both offers. The details are omitted.

Proposition 1 There is no pune stmtegy equilibrium in the B-game oj the puólic offers

model.

Proof: The proposition is proved in several steps.

Step 1: f3oth sellers cannot accept Bz's offer. Ií both sellers do accept Pz from Bz, then

pz ~~ from Lemma 2. Let B~ deviate and offer Pz - Pz - e where e 7 0 and

b~ ~ vz - P~. Note tliat such Pz exists for b high enough.

To sustain original equilibrium, both sellers must reject óoth offers since acceptance of

P~ will give B.2 a payoff of ó~ ~ vz - PZ. But, if both sellers reject Pz, then there is a

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9

continuation payo(f ( st, sz) in the S-game such that b(sl, sz) c~ tt6, ttd~. From Lemma

l, it is easy to check that this is not true. Hence, Step 1 is proved.

Ste~i 'L: Both buyers cannot accept an offer from the same seller in the S-game.

Suppose Bt and Bz both accept p~ from S~. Now, if p; - p~ - p, then Bt will deviate

and accept p from S;. This will give Bt a payoff of (vl - P), whereas acceptance of P

from S~ gives z wl - P~- t,b~ G vt - p since p G ,}d . So, P, ~ P;.

Let S~ raise the offer "slightly" to P~ G P,. To sustain original equilibrium, both

buyers reject any such P~. Hence, there is a continuation payoff (61i bj) in the B-game

such that b(bt,b~) 7(vt -~, t}d ). Lemma 2 and Step 1 rule out this possibility.

SLep :3: In the S-game, if B; rejects both offers, then B~ musL also reject both offers.

Suppose first that BZ accepts an offer whereas Bt rejects both offers. Then,

( 3

R(B')Cv~-(1-~b)Gblvs-lfó ~b4~ (1)

where bz is the minimum payoff of BZ in the B-game. To check the last inequality3

in O, notice that if both buyers' offers are accepted in the B-game, then Pz G t~b.

For, suppose P~ ~ d,td. Let B~ rteduce the ofíer to P2 - d~ -f e. Since Pl ?~t6,

Bz's offer can be rejected only if there is an S-game continuation payoff (st, sz) such

that b(st.sz) 1~t~d, d~t~b ~. But, since there is no such payoff vector, P~ G dtrá. So,

6z ? vZ - d tlá, as was to be shown.

But, (2) establishes that ií B~ rejects both o(fers, then Bz must also reject both offers.

Suppose now that Bl accepts an offer of P~~, whereas Bz rejects both offers.

Letting S~ denote the unmatched seller, R(S~) - d~. Let Sz deviate and make an offer

if d~ f c, where e 1 0. Then, to sustain original equilibrium, both buycrs reject both

offers. But, this requires buyer continuation payotis of (vt - d~, vz - d~). But, no such

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Io

payoffs are possible,thereby proving Step 3.

SLep 4: In view of Steps 2 and 3, the only possible eyuilibrium in the S-game is for both

seller offers to be accepted (Case (a) of Lemma I). In Step 1, we have already ruled out

both sellers accepting an offer from Bz. The other candidate equilibria in the B-game

are now shown to be impossible.

First, both buyers' offers of P, and P2 cannot be accepted. If both buyer offers aze

b' ( ó' ) then Bz can deviate andindeed accepted, then P~ C vz(I - ~tb). For, if PZ 1 v2 1- lta ,

offer P~ - vz(I - 1}6). Since P, ~ tlá, and since rejection of Pz implies rejection of Pl,

ó óTthis requires seller continuation payoffs (s,,s~) such that 6(s,,s2) ?~ltó,v2(1 - lfó)~.

So, PZ c vz(1 - i}6).

Let now S~ reject B~ and accept B,'s offer of p,. Then, R(SZ) ? z~i}ó }~~ ~

v~(1 - rtó ) for D suf~iciently close to 1. Hence, both buyer offers cannot be accepted.

Next, note that if one seller rejects both offers, while S; accepts B2's offer, then

' - e. For e sufficientlR( B, )- b,~d . B can deviate to a price offer of p- vl (1 - ltó ) Y

small, P 1 ~tb - ës, where s is the maximum continuation payoff in the S-game. So,

B,'s offer cannot be rejected.

The only other possibility is that B~'s offer is rejected in equilibrium. Then, R(B2) -

6~, and Bz can deviate to PZ - v2(1 - 1}b) - e. It is easy to check that a rejection of

P2 cannot be sustained.

This completes the prooí of the proposition. ~

Proposition 1 leaves open the possibility of an eyuilibrium in the S-game with óoth

pairs being matched. We now show that there is indeed a unique pure strategy equilib-

rium in the S-game where both are matched at a price of Pz -~~.

Proposition 2 The unique pui~e slrategy equilibrium oJ the S-game in the public offers

model involves both sellers offeréng a price p' -~, and both pairs are matched.

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11

Proof: We first show that this is indeed an equilibrium.

Let .S, aud 5'1 both u(Tcr p' -~ '~ta.

B; accepts o(Cer frorn S; for i- 1,2. Also, if for any vector (P;, P~) with f; - p' and

P~ 1 p', Bz rejects both offers, while Br accepts P;. (This is, of course, not a complete

description of buyers' responses.)

Then, it is trivial to check that these strategies constitute an equilibrium.

We now show why this is the only equilibrium in the S-game. Let (P,, Pz) be equi-

librium offers. From Lemma 1(a), P; G rtb. So, the only other possibility is that

P, ~ P~ G rtb, where P; is the price accepted by B;,i -],2. But, there the seller

o(Tering Pz will deviate and increase offer to Pz - P~- 1- c. Bl cannot reject this offer,

and so ( Pr, f'~) cannot be equilibrium offers.

Remark 1: [t is woreh pointing out that i[ the sellers are also heterogeneous, then there

will not be any pure strategy eyuilibrium in the S-game. Thus, in cases where agents

on both sides of the market are heterogeneous, ehere will not be any pure strategy

equilibrium in the public offers model.

4 The Targetted Oífers Model

In this section, we analyse the nature of pure strategy equilibria in the targetted offers

model. The principal result of this section shows that only one pair of agents can be

matched in the first period of any pure strategy equilibrium, the other pair of agents

being matched in the next period. This is true irrc~pective of whether buyers or sellers

rnake o(Cers. It is worth pointing out that the ine„(J~iciency arising out of delay in reaching

agrc.rment is not ehe result of "wrong" matchings arising from random matchings (as in

Ilcndon and Tranaes (1991)), or incomplete information.

Let b satisfy the following inequality.

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v2 ~ ó~ (2)v~ 1 fó-ó3

The results in this section hold for all ó?~. The next lemma is proved in the ap-

pendix. Let s denote the maximum seller payoff in the S-game of the targetted offers

model.

Lemma 3 If ê~ 6, then s G Ifá.

We also describe in Table 1 the candidate equilibrium configurations in the targetted

offers model.

Table 1:

Possible Equilibrium Configurations in the Targetted Offers Model

Cases 1-3 pertain to the S-game, Cases 4-6 to the B-game. We have assumed, w.l.o.g.,

that matches take place between B; and S;.

Case 1. Both seller offers accepted in equilibrium. Then, P; C ~~6; where P, for i- 1, 2 is

the price agreed by (B;, S;).

Case 2. S~ ofFers p~ to B~ who accepts. S~ and Bz do not have an agreement but agree in

the two-player game with Bz as proposer. Here

ë~vz óvZR(S~) - 1 f ó' B(B2) - 1 t ó.

Case 3. S2 offers pz to B~ who accepts. B~ and Si agree in the two-player subgame with

Bi as proposer.ó2v~ Áv~

R(S` )- 1 f ó, R( B~ )- 1} 6.

Case 4. Bot}i pairs reach agreement in the same period in the B-game. Then, P; ~

where p; is price agreed by (B;,S;) for i- 1,2.

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Case 5. Br o(fers pg to Sr, who accepts B~ and Sz agree in the two-player subgame with

Sz as proposer.ó~v~ áv~

R(Bz) - 1 t b, R(Ss) - I f ó'

Case 6. Bz offers pz to Sz who accepts. Br and Sr agree in the Sr-subgame.

ávl óvlR(Br) - 1 f a, R(sr )- 1 f b'

Proposition 3 If 6 1 á, every pure strategy equitibrium in the targetted ojjers modei

must exhibit delay. -

Proof: Thc proof is broken up into several steps.

Step 1: Case 6 cannot occur in equilibrium.

In view of Lemma 3, Sl cannot reject any offer higher than

and make an acceptable offer of ~r6 f e.

~ So, Br can deviaterfa~

Step 2: Case 2 cannot occur in equilibrium.

Note that from Cases 4 and 5, bz C rtá, where bz is the largest equilibrium payoff

of B2 in the B-game. Hence, Sz can deviate and make an offer of ~- e to Bz.

Since B~ must accept this offer, Case 5 cannot be an equilibrium.

Step 3: If both pairs are matched in equilibrium, then P, - l~av; in the B-game, and

P, - ,}d in the S-game.

Consider the B-game. We know that P; 1 rtbv;, since a rejection by one seller

induces the Rubinstein subgame. Suppose P, ~ rtbv;. Let B; deviate and offer S;

a price p' such that P, ~ p' ~~lá. S; can reject this offer only if S~ rejects P~.

This implies that there is a continuation seller payoff ( sr,sz) in the S-game such

that é(sr, s2) ~ (P', P~). This cannot happen in Cases 1 and 3, while Case 2 has

been ruled out in Step 2. So, P; - ltb.

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Thc proof that P; - ~tá in the S-game is analogous.

titc~p 4: PB ? ~.

I,et ,y deuote the miuimum seller payo(í in the .S-ga~ne. Since a selkr accrpts PH,

we must have

PB ? bsz

~ bmín(1f b' 1 {.

bv~' PB)

1 bmin(1} 6' pz)

(3)

sincc bz 1 ~.

Consieer Case 3 of Table 1. If S~ offers a price p- b}1át e to B~, then B~ must

accept unless Bz also rejects the o(fer from Sz. So, there is a continuation payoff

vector ( 6~, b2) such that b(6~, bz) 1(vl(1- ~}ó), vz-p'z). The only possibility is that

(6~, 6z) is obtained from Case 5, where R(Bz) - ó~. tfence, pá ? vz(1-lta) ? t;~~

From (3), PB ? ~-

Step 5: Both pairs cannot agree in equilibrium in the S-game.

Proof: Suppose (S;, B;) are matched for i- 1, 2. Then, we must have P; - ~}ó from

Step 3.

Let Sz deviate and offer p- ~ tE where e is a small, positive number. Then B~ must

reject p. Hence, there is an equilibrium payoff 61 in the B-game such that bb~ 1 vi -~.

But, since pB ? i~á, and P~ -~td if both pairs are matched in the B-game, there is no

such eyuilibrium payoff for Bi.

Hence, both pairs cannot be matched in equilibrium.

Step 6: Both pairs cannot be matched in equilibrium in the B-game. If they are matched,

then p; - t,ó. Let B~ deviate and offer a price arbitrarily smaller than 1}6 to

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S~. Sz must reject both offers. This implies that ës 1~}ó. But, since the only

candidate equilibrium in the S-game in Case 3, s G max(pz, 61t6 ). Since Bz accepta

pá, uz - pz 1 6~~, where ~ is the minimum equilibrium payoff of B~ in the B-game.

So b~ - 6~ (from Case 5), and pz C v~(1 - 1}6). For ó~ b, 6á1 vz(1 - rta),

and hence s G 1}6.

So, Sz cannot reject an of[er of (~}b - e).

't'his cornpletes the proof of Proposition 3.

Proposition 3 does not rule out the existence of pure strategy equilibria. Notice,

however, that in the process of proving Proposition 3, we have ruled out Cases 1, 2, 4

and 6. There[ore, the equilibria, if any, must be in Cases 3 and 5. In the S-game, Bz is

in the first agreement. In the B-game, B~ agrees first.

Let ó satisfy the following inequality.

v~ C ós

v~-lfó-ó~(4)

Note that b ~ ë.

Proposition 4 For ó 1 6, lhe Jollowing descrióes a pure slrategy equilíbrium configura-

tion in tlae targetted ojjers modrl.

S-game

Sz proposes pz - v~(1 -~~b) to Bz, who accepts, S~ asks for v~ from (or does not

make an offer to) B~, who rejects. A[ter SZ and Bz have left the market, B~ offers a

price of ~tó to Si, who accepts. -

B-gamc

B~ proposes pe - óv~(1 - ~~b to Sz, who accepts. 6z and Si do not agree until after

(B~, S~) have left the market, when S~ o[[ers ~ to Bz, who accepts.

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Proof: This is sustained by the following equilibrium strategies. (rAcceptanceT implies

acceptance of the best possible offer that satisfies the condition.)

(i) S~ propuscs yz to B~. S~ makes an irrclevanL ofCer, as explained above.

(ii) Bz accepts p G p'z irom Sz if S~ either makes no offer or a"non-serious" offer to

B,. If S, offers p C i}á to Br, Bz rejects pz but accepts p G p2.

(iii) B~ accepts p such that v~ - p 1 ó[vl - óvZ(1 - Ita)].

(iv) In the B-game, Br proposes pB to Szi where pB - óv2(1 - ~~a).

B2 proposes 0.

(v) S2 accepts offers p? pe unless B2 proposes a price p? ~}b, when SZ rejects offers

p G pB.

(vi) S~ accepts the highest price above a6.

These constitute our equilibrium provided Á ~ ó. Note that in (iii) B~ must reject

the offer o[ i}6 if Sl deviates and offers this. Given that B2 also rejects SZ's offer, B~'s

payoff is then ê( vr -óvz(1 - rta)) ~,ta if ë~ ë.

In (vi), St must reject an offer of v2(1 -~ta) from B2 in order to sustain the-equilib-

rium. This requires that v2(1 - ~~a) C rta, and explains the value of ó.

It is straightforward to check that the above strategies constitute an equilibrium.

5 Private Oífers Model

It is clear from the description o[ the equilibrium strategies in Propositon 4 that any

equilibrium (for high ó) in the targetted ofíers model must have the feature that off the

equilibrium path, a player may reject the same offer that he should accept in equilibrium

because the offer to the other responder has changed. This is not a particularly "intu-

itive" feature of equilibrium. In the equilibrium described above, it does not even result

from a change in this player's expectation of future payoff. One might consider looking

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for equilibria in the private offers model, where a player's response must depend only

on the offers he or she receives. Clearly, the results in the previous section indicate that

there cannot be any pure strategy equilibria in the private offera model. We, therefore,

turn to a consideration of mixed strategy equilibria in this model. The principal result

of this section is to show that there is a unique mixed strategy equilibrium.

In the S-game, seller S;'s strategy consists of the 4-tuple [F;,, F;2, a;, l - a;]. Here,

F;~ is the cumulative distribution function of ptices offered to B„j- 1, 2. rr; is the

aggregate probability of an offer being made to B,, while ( 1 -~r;) is the probability of

an offer being made to B2.

In the B-game, buyer B;'s strategy consists of a 4-tuple [G;,,G-,z,a;, 1- a;]. These

have an obvious interpretation.

Lemma 5 Fork- 1, 2, F,k and Fzk must have common support if offers to Bk are made

wilh posilive probability by óoth sellers.

Proof: Suppose F,~ has support [~i,,p,], while Fzk has support [~,pz] with [~,pl] ~

[Pz, Pz].

Let p, G pz. Let p E(pi,pz). When Bk dces not receive an offer írom Szi an offer of

p must be accepted. Otherwise Sz's payoff is á~ since Bk will become proposer in the

Rubinstein game with S~ in the next period. Since all pure strategies in the support of

~2k must give Sz the same payoff, S2's expected payoff is á~, while Bk's payoff is }ió

whenever S, does not make an offer. But, Sz can deviate from Fzk and offer Bkitá.

Ilence, any p E pi , pz is accepted. But then take prices p, p' such that ~ G p C p' G pz.

Sz's expected payoff from offers p, p' cannot be equal. Ilence, ~, -~.

Suppose p, ~ pz. Then there cannot be any offers by S, in (p~,p~), since an offer at

p, will be accepted by Bk when it is the only offer (an offer between (px, p, ) is accepted

only ií it is the only offer), and p, is better than everything lower for S,.

But then Sz can deviate from pz, offer p~ - e and obtain a higher payoff than from

the p2 offer.

Lemma 6 In the S-game, it cannot be an equilibrium for any óuyer to receive two

degenerate price ofjers.

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Proof: Supposc Bk recciv~s offer p~ and p~ from S~,Sz with probabilities ~r~, a2 respec-

tively. In view of Lemma 4, pi - p2. But, then either seller has an incentive to lower

the price offer slightly.

Proposition 5!n lhe S-game oj the private offers model, the unique mized stmtegy

equilibrium is described by the jollowing equations.

(1~-ó)x-vz~,F,i(x) - Fx,(x) - (1 t ó)x - b2v2

with support ~~, ~].

á(1 f b) - v2

~' - x(1 f ó) - ó~vz

az-1

(5)

(6)

(7)

S~ offers B~ a price of 1} ó with probability ( 1 - a~) (8)

v2The expected payoff to each seller is

1 f ó (9)

Proof: Let F~~, F,2, nl, 1 - pi~], [Fzl, F22, nz, l- a2] be any pair of equilibrium strategies

in the S-game. Let E;~(x) be the expected payoff to S; when a price of x is offered to

B~ .

To calculate E~~(x), note that (1 - az f x~(1 -!~~(x)) is the probability that B~ will

accept an of[er of x from S~, while azFz~(x) is the probability that such an offer will be

rejected. In tlie latter case, S~ obtains b}~á from the Rubinstein game with Bz.

Hence,

ë'vZ (10)Fii(x) - x(1 - xs t xs(I - Fs,(x)) f nsFzi(x)1}ó- ~~i

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From (10),

We now calculate Elz(x).

Note that El,(x) - E,z(x) since all (pure) strategies must give Sl the same expected

payoff. So,

(1 f ó)(x - K,)~zFz,(x) - (1 f ó)x - ëzvz

sE,z(x) - x(~z i- (1 - ~,)(1 - Fzz(x)) f (1 - az)Fzz(x) ~-~b - lí, (12)

From (12), (1 - az)Fzz(x) - lta x-K,ln order for Fzz to be increasing in x, we

- (]tó)z-6 v,'

need li, 7 ót~b. So, x~ Kr ~ ót~á. But, then for all ó~~,vz - 6á C i~ó. This

implies that Bz should reject any offer of x whenever Bz rejects only one offer. Hence,

E,z(x) - x(1 - ~z)(1 - Fzz(x)) f ~z 1 f b } (1 - ~z)Fzz(x)1 } ó - lí,

or,

Fzz( )- K~- azób- x(1 - xz)

x(1 - ~z)b - x(1 - ~2)

(13)

(13) irnplies Lhat either Fzz is a decreasing function of x or Fzz(x) 1 1, which is impossi-

ble. IIence, rrz - I if 5', bids to Bz. Now, because Sz only bids to Bl, S, only uses a pure

strategy bid ~ to Bz. This implies that K, -~. Since F„ and Fz, have common

support, expected payoffs to both sellers must be ~.

Finally, note that by analogy, ~r,F„(x) - ~}b x-v, Setting F„(i) - 1, we get- (,ta)~-a ,,,.(,ta)i-uz

~~ - (,ta)r-a',n.

The value of i will be determined later.

This completes the proof of Propositíon 5.

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We now turn our attention to the buyers' game. For i- 1, 2, let [G;1, G;z, al, l- al]

d~~not~~ a pair of cquiliLríum strategiiw of [J;. Let I[;i(x) dettotc tlte expccted payofl' of

L~; when x is the price offered to s~ and L; be B;'s expected payoff. Then,

z

Btiíx) -(ut - x)asGzl(x) t [1 - az f az(1 - Czt(x))] 1 tb-L, . (14)

Hence,

~zGzl(x) -

6~ v,Ll - ]tb (15)

Alsu,

a~„vl-x- tib

j 2

i~12(.T) - (1~I - x)[( I - ~2)~,21(x)1 } l(1 - ~2)(~ - CZ2(x)) f 1~21 ~}~ - GI (ís)

í IlefefOfC,

a~,~,

(1 - ~rz)Gzz(x) - Ll - ~tb~„ " (17)~vl - x - ]tb

Similarly,

x V x~r c x 1- ~ ~r 1- Gll( )) a2vZ - ()az,( )-( z- )[ 1 1t( )~( t)]f t( x lfa-Lz 1g

Hence,

Lz-alá~-(í-~1)(vz-x)AlGll(x) - b~

Vy - 2 - 1}6

(19)

Lz - (1 - ]rl)b~ - ~t(vz - x) (20)(1 - ~t)GtzÍx) - a~V~-x- itb

Note that Bl has to be indifferent between offering to Sl or Sz when a, is positive.

Setting Gzl(il) - 1- Gzz(iz), we get from (15) and (17),

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zL' - 1 f ó(1 - Az) t( vr - ir)AZ (21)

z- ~}ó~z t ( vt - iz)(1 - ~z) ~ (22)

Sirnilarly, we can obtain

Lz -z

1 f ó~~ f (vz - ?r)(1 - ~r)z

lfó(1-u,)f(vz-rz)~rr

(23)

(24)

zLemma ? In equalions (21) to (2.{), xl - xz - r~, and ir - iz -~ ~}r}dá

Prooi: LeL [y~, y~] be the support of f31's offer to s~, and (tv~, w~] denote the support

of l3z's offars. Suppose y~,w~ 7~. An argumenL analogous to Lemma 4 shows that

y~ - w~ -~~. If Bz makes an o(Cer of ~„ it wins with positive probability only if Bl

rnakes an o(Cer to s;, i~ j. I3ut, if I1z faces no competit,ion, the optimal offer is ~~.

Therefore, in equilibrium, a~ -~ for j - 1,2. Thcrefore, ~r - xz.

We now show that i' - iz. Suppose ir ~ iz. Now, suppose Bz deviates and switches

some probability mass M from Sr to Sz. Then, he gains M(vz - iz). The loss is L,

where ~~ zL-~z {(vz - x)(2 f ZGrr(z)) t 2(1 - Gu(z)1 t

ó)}9sr(x)dx

G ~~~(uz - x)(2 f 2)9z,(x)dxz

G(vz - iz)M, where M - Gz~(xi) - Gzr(~z).

1'herefore, ï r - ïz - i. This also yields A; - z for i- 1,2.

To calculate i, substitute x- i~ in (23) and (24) to obtain Lz - z~-r~vz. We

substitute this in ( 19). Also, use rrr - 2 and calculate Lhe value i such that Grr(x) - 1.

'This yields i - ~ (r}~}bd~~~

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Proposition 6 In the B-game of the private offers model, the unique mized strategy

ryuilibriuna is described by the jollowing.

`lL~ - aita - ( v~ - x) (25)Gt~(x) - a~vz-x- ~ta

~O-6~ v,2(L~ - 1}6 ) (26)

't~ x - 6~(vi - x - ita

with comnaon supports

óv2 (1 f 2ë - óz)vs (27)~1fó~ 2(1 tó)

1ni-~x-2

1 L fê-~ó2 vz(1 ~-2b-b2)~L~ - 2~t'~ ( 1-} À)- 2 1 f ë

z

L~ - 2(1 f ó)v~

(2s)

(29)

(30)

bf Proof: Lemma 6 has established (27) and (28). Substitution of n~ - ~ in f 15) and

(17) gives (26), while a~ - z together with (19) and (20) establish (25). Substitution of

x and i from (27) into (21) and (23) yield (29) and (30).

In order to show uniyueness, we note the following:

(i) No pure strategy eyuilibrium exists.

(ii) If B; were to make offers only to S;, i- 1, 2, the offers would have to be pure

strategies, and hence would not be equilibria under (i).

(iii) Therefore, the only possibility is if B~ makes offers only to S~ say, and BZ makes

offers to both sellers. In this case, the upper bound of the support for the mixed

strategy to S~ would be ~. The mixed strategies then have mass points at x.

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(The details of the calculations are omitted.) But, then either B; could deviate

and s}~ift his or her mass point a small amount upwards increasing expected payoff.

So, this cannot be an equilibrium.

The case where Bi offers to both is analogous. In order to complete the check that

the strategies described above constitute an eyuilibrium, we also need to verify that

tl~e sellers in the S-game and buyers in B-game do not gain by making rejected

offers. The expected seller payoff in the S-game is ~, while the maximum seller

payoff in the B-game is ~z~~~vz. Hence, sellers are better off in the S-game.

Sirnilarly, both buyers are better ofï in the B-garne.

Note that i, the maximum price offered by scllers to B,, is irrelevant to the sellers'

expected payoffs so long as i~~. But, i must satisfy the restriction -

Áv~v~ - z 1 rnaa(óL,, I}á) (31)

(31) ensures that B, is willing to accept i in the S-game. For á sufficiently large,

L, ? }1á, so that i- v~ - êLi.

This completes the proof of Proposition 6.

Of course, the mixed strategy equilibrium involves coordination problems, usual in

simultaneous move models, that generate a probability of delay. However, we find

the mixed strategy equilibrium intuitively more plausible than the pure strategy

equilibria in the previous models. Here, when buyers make offers, prices essentially

converge to 2, the lower of the two ~Rubinstein~ prices. When sellers make offers,

sellers' expected payoffs also equal ~. Of course, uniform pricing is a necessary

condition for an allocation to be in the core. In this case, because of the positive

probability of delay, the allocation is inefficient.

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We remind the reader that ó satisfies (2).

Lemma 4 If b) b, then s C I}6.

P'rom Table 1 and Lemrna 0, we have

s C max(I }b,Pi~Pz)

But, for i - 1,2,p; G v; - b6 , where 6; is the minimum payoff of B; in the B-game.

Ilcnce,

vs G rnax ~ I } 6, vr - 66„ v2 - b62 (.2)

We consider only the possibilities that the maximum in (A.2) is attained at v;-db..

Suppose v, - b6, 1 vz - b62. Let b, be obtained írom either Case 4 or-Case 5.

Then,

sCv,-b6, Gv,-b(v,-bs)

The second inequality in (A.3) follows because no seller can reject an offer higher

than bs from B,. But (A.3) yields s G,tá. The other possibility is that b, is

obtained from Case 6, so that b, - b,tb. Hence, s c v,(1 - lta). But, thenz

ós G v2(1 - l~a). 50, B, can make a price offer arbitrarily close to v,(I - itó),

and this cannot be rejected by S,. This would rule out Case 6 as an equilibrium.

Suppose v2 - b62 1 v, - bb - 1. If 6i is obtained from Case 4 or Case 5, then in

exactly the same way as above, it will follow that s C,tó. If 6z is obtained from

ó' G~- since b 1 b.Case 5, then s C v2(1 -,}a -,ta

This completes the proof o[ Lemma 3.

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of Economics Discussion Paper.

M. Shubik (1982), Came Theory Jor the Socin( Sciences, MIT Press.

Page 31: Tilburg University Rubinstein auctions Chatterjee, K.; Dutta, B. · Bhaskar Dutta Indian Statistical Institute, Dclhi Centre 7, S.J.S. Sansanwal Marg New Delhi, 110 016 India May

Discussion Paper Series, CentER, Tilburg University, Thc Netherlands:

(For previous papers please consult previous discussion papers.)

No. Author(s)

9355 'l,. Yang

9356 L. van Uammc andS. Hurkens

9357 W. Guth and B. Peleg

9358 V. Bhaskar

9359 F. Vella and M. Verbeek

9360 W.B. van den Flout andJ.I'.C. Blanc

9361 R. I leuts and1 dc Klcin

9362 K.-E. Wárneryd

9363 P.J.-J. Herings

9364 P.J.-J. Herings

9365 F. van der Ploeg andA. L. Bovenberg

9366 M. Pradhan

9367 Ii.G. Bloemen andA. Kaptcyn

9368 M.R. Baye, D. Kovenockand C.G. de Vries

9369 T. van de Klundert andS. Smulders

9370 G.van der Laan andD. Talman

9371 S. Muto

9372 S. Muto

Titlc

A Simplicial Algorithm for Computing Robust Stationary Pointsof a Continuous Function on the Unit Simplex

Commitment Robust Equilibria and Endogenous Timing

On Ring Formation In Auctions

Neutral Stability In Asymmetric Evolutionary Games

Estimating and Testing Simultaneous Equation Panel DataModels with Censored Endogenous Variables

The Power-Series Algorithm Extended to the I3MAP~PH~1Qucue

An (s,q) Inventory Model with Stochastic and Intcrrelated Leadf i mcs

A Closer Look at Economic Psychology

On the Connectedness of the Set of Constrained Equilibria

A Note on "Macroeconomic Policy in a Two-Party System asa Repeated Game"

Direct Crowding Out, Optimal Taxation and PollutionAbatement

Sector Participation in Labour Supply Models: Preferences orRationing?

The Estimation of Utility Consistent Labor Supply Models byMcans of Simulatcd Scores

The Solution to the 'fullock Rent-Seeking Gamc When R ~ 2:Mixed-Strategy Equilibria and Mean Dissipation Rates

The Welfare Consequences of Different Regimes ofOligopolistic Competition in a Growing Economy with Firm-Specific Knowledge

Intersection Theorems on the Simplotope

Alternating-Move Preplays and vN - M Stable Sets in TwoPerson Strategic Form Games

Voters' Power in Indirect Voting Systems with Political Parties:the Square Root Effect

Page 32: Tilburg University Rubinstein auctions Chatterjee, K.; Dutta, B. · Bhaskar Dutta Indian Statistical Institute, Dclhi Centre 7, S.J.S. Sansanwal Marg New Delhi, 110 016 India May

No. Author(s)

9373 S. Smulders andR. Gradus

9374 C'. Fcmandcz,J. Osiewalski andM.F.J. Steel

9375 E. van Damme

9376 P.M. Kun

9377 A. L. Bovenbergand F. van der Ploeg

9378 F. l~huijsman, B. Pcleg,M. Amitai 8c A. Shmida

9379 A. Lejour and H. Verbon

9380 C. Fcrnandez,J. Osiewalski andM. Steel

9381 F. de Jong

9401 J.P.C. Kleijnen andR.Y. Rubinstein

9402 F.C. Drost andB.J.M. Werker

9403 A. Kaptcyn

9404 H.G Bloemen

9405 P.W.J. De Bijl

9406 A. Dc Waegenaere

9407 A. van dcn Nouwcland,P. Burm,W. van Golstein Brouwers,R. Groot Bruinderink,and S. Tijs

9408 A.L. Bovenberg andF. van der Ploeg

Title

Pollution Abatement and Long-term Growth

Marginal Equivalcncc in v-Sphcrical Modcls

Evolutionary Game Theory

Pollution Control and the Dynamics of thc Pirm: the Effects ofMarket Bascd Instrumcnts on Optimal Pirm Invcstments

Optimal Taxation, Public Goods and Environmental Policy withInvoluntary Unemployment

Automata, Matching and Foraging Behavior of Bees

Capital Mobility and Social Insurance in an Integrated Market

"fhe Continuous Multivariate Location-Scale Model Revisited:A Tale of Robustness

Speciftcation, Solution and Estimation of a Discrete TimeTarget Zone Model of EMS Exchange Rates

Monte Carlo Sampling and Variance Reduction Techniques

Closing the Garch Gap: Continuous Time Garch Modeling

The Measurement of Household Cost Functions: RevealedPreference Versus Subjective Measures

Job Search, Search Intensity and Labour Market Transitions:An Empirical Exercise

Moral Hazard and Noisy Information Disclosure

Redistribution of Risk "fhrough Incomplcte Markets withTrading Constraints

A Game Theoretic Approach to Problems inI clccommunicution

Consequences of Environmental Tax Refortn for InvoluntaryUnemployment and Wclfare

Page 33: Tilburg University Rubinstein auctions Chatterjee, K.; Dutta, B. · Bhaskar Dutta Indian Statistical Institute, Dclhi Centre 7, S.J.S. Sansanwal Marg New Delhi, 110 016 India May

No. Author(s)

94119 P. timil

9d 10 J. l:ichberger andD. Kelsey

941 I N. Dagan, R. Serranoand O. Volij

9412 H. Bester andE. Petrakis

9413 G. Koop, J. Osiewalskiand M.I~.J. Steel

9414 C. Kilby

9415 H. Bcstcr

9416 J.L(;. I.cmmcn :mdS.C.W. Eijffinger

9417 J. de la Horra andC. Fernandez

9418 D. falman and Z. Yang

9419 H.J. Bierens

9420 G. van der Laan,D. Talman and Z. Yang

9421 R. van den Brink andR.P. Gilles

9422 A. v:u, Socst

9423 N. Dagan and O. Volij

9424 R. van den Brink andP. Borm

9425 P.ILM. Ruys andR.P. Gillcs

9426 l. C~allan andA. van Soest

9427 R.M.W.J. Beetsmaand F. van der Plceg

Title

Arnoldi 'IYpc Mclhuds lirr I~:igcnvaluc Calculaliun: '1'hwry and

Experiments

Non-additive Beliefs and Game 'fheory

A Non-cooperative View of Consistent Bankruptcy Rules

Coupons and Oligopolistic Price Discrimination

Bayesian Efficiency Analysis with a Flexible Ponn: "fhe AIMCost Punction

World Bank-Borrower Relations and Project Supervision

A Bargaining Model of Financial Intermediation

I~hc Price Approach to Pinancial Integration: DecomposingEuropean Money Marke[ Interest Rate Differentials

Sensitivity to Prior Independence via Farlie-Gumbel-Morgenstem Model

A Simplicial Algorithm for Computing Proper Nash Equilibriaof Finite Games

Nonparametric Cointegration Tests

Intersection Theorems on Polytopes

Ranking the Nodes in Directed and Weighted Directed Graphs

Youth Minimum Wage Rates: The Dutch F.xperience

13ilateral Comparisons and Consistent Fair Division Rules in theContext of Bankruptcy Problems

Digraph Competitions and Cooperative Games

The Interdependence between Productíon and Allocation

family Labour Supply and Taxes in Ireland

Macrceconomic Stabilisation and Intervention Policy under anExchange Rate Band

Page 34: Tilburg University Rubinstein auctions Chatterjee, K.; Dutta, B. · Bhaskar Dutta Indian Statistical Institute, Dclhi Centre 7, S.J.S. Sansanwal Marg New Delhi, 110 016 India May

No. Author(s) Titlc

9428 J.I'.C'. Kleijnen andW.van Groenendaal

9429 M. Pradhan andA. van Soest

9430 P.J.J. Hcrings

9431 H.A. Keuzenkamp andJ.R. Magnus

9432 C. Dang, U. 'falman andZ. Wang

9433 R. van den Brink

9434 C Veld

9435 V. Feltkamp, S. Tijs andS. Muto

9436 Q-J. Otten, P. Borm,B. Peleg and S. Tijs

9437 S. Hurkens

9438 .L-J. licrings, D. Talman,and Z. Yang

9439 li. Schaling and U. Smyth

9440 1. Arin and V. Feltkamp

9441 P.-J. Jost

9442

9443

J. liendor, D. Mooklterjce,und D. Ray

G. van der Laan,D. I~alman and Zaifu Yang

9444 G.J. Almekindcrs andS.C'.W. Eijffinger

9445 A. Ue Waegenaere

fwo-s[age versus Sequcntial Sample-size Determination inRegression Analysis of Simulation Experiments

Household Labour Supply in Urban Areas of a DevelopingCountry

Endogenously Determined Price Rigidities

On Tests and Significance in Econometrics

A Homotopy Approach to the Computation of EconomicEquilibria on the Unit Simplex

An Axiomatization of the Disjunctive Permission Value forGames with a Permission Structure

Warrant Pricing: A Review of Empirical Research

Bird's Tree Allocations Revisíted

The MC-value for Monotonic NTU-Games

Learning by Forgetful Players: From Primitive Formations to

Persistent Retracts

The Computation of a Continuum of Constrained Equilibria

I'hc Efïects of Inllation on Gruwlh and Flucluations inDynamic Macroeconomic Models

The Nucleolus and Kernel of Veto-rich l~ransferable UtilityGames

On the Role of Commitment in a Class of Signalling Problems

Aspirations, Adaptivc Lcarning and Cooperation in RepeatedGarnes

Modelling Cooperative Games in Permutational Structure

Accounting for Daily Bundesbank and Federal ReserveIntervention: A Friction Model with a GARCH Application

Equilibria in Incomplete Financial Markets with PortfolioConstraints and Transaction Costs

9446 f:. Schaling and D. Smyth The Effects of Inflation on Growth and Fluctuations in

Dynamic Macroeconomic Models

Page 35: Tilburg University Rubinstein auctions Chatterjee, K.; Dutta, B. · Bhaskar Dutta Indian Statistical Institute, Dclhi Centre 7, S.J.S. Sansanwal Marg New Delhi, 110 016 India May

No. Author(s)

9447 G. Koop, J. Osiewalskiand M.P.J. Stccl

944R I I. Il:micrs, .I, tiui.js,S. I i.j, nnd I'. Bonu

9449 ( i.-J. Otlcn, I I. I'clcrs,and O. Volij

9450 A.L. Bovenberg andS.A. Smulders

9451 F. Verboven

9-3~' P.J.-J. Herings

9453 D. Diamantaras,R.P. Gilles andS. Scotchmer

9454 1:. dc Jung, 'f. Nijmanand A. Riicll

9455 F. Vclla and M. Vcrbcck

9456 H.A. Keuzenkamp andM. McAleer

9457 K. Chatterjee andB. Dutta

Title

Hospital Efficiency Analysis Through Individual Effects: ABayesian Approach

I'hc Splil (' orc lix Scyucncing (iamcs

I wu ('haraUcriralions of Ihc Unifonn Rulc lix DivixionProblems with Singlc-Pcaked Preferences

fransitional Impacts of Environmental Policy in an EndogenousGrowth Model

International Price Uiscrimination in the European Car MarketAn Econometric Model of Oligopoly Behavior with ProductDilTèrenliation

A Globally and Universally Stable Price Adjustment Process

A Note on the Decentralization of Pareto Optima in Economieswith Public Projects and Nonessential Private Goods

Pricc Effects ofTrading and Components of lhe Bid-ask Spreadan thc Paris Boursc

I'wu-Stcp Estimation of Simultaneous tiyuation Pancl DataModels with Censored Endogenous Variables

Simplicity, Scientific Inference and Econometric Modelling

Rubinstein Auctions: On Competition for Bargaining Partners

Page 36: Tilburg University Rubinstein auctions Chatterjee, K.; Dutta, B. · Bhaskar Dutta Indian Statistical Institute, Dclhi Centre 7, S.J.S. Sansanwal Marg New Delhi, 110 016 India May

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