Complete Information Environment Research Articles

Getting Dynamic Implementation to Work

We develop a new class of two-stage mechanisms, which fully implement any social choice function under initial rationalizability in complete information environments. We show theoretically that our simultaneous report (SR) mechanisms are robust to small amounts of incomplete information about the state of nature. We also highlight the robustness of the mechanisms to a wide variety of reasoning processes and behavioral assumptions. We show experimentally that an SR mechanism performs well in inducing truth telling in both complete and incomplete information environments and that it can induce efficient investment in a two-sided holdup problem with ex ante investment.

Level-k reasoning in school choice

Boston Mechanism (BM) and Deferred Acceptance (DA) are two competing algorithms in school choice. BM is manipulable whereas DA encourages truth-telling. Recognizing heterogeneous sophistication of students, we use the level-k model to analyze students' strategies under BM in a complete information environment with strict school priorities. Because students tend to manipulate first choice under BM, we characterize the first choice reported by students at all possible sophistication levels. In a general framework we show that BM is no less efficient than DA, and in two specific belief settings we further show that it is as if students run DA in their minds when they make level-k reasoning under BM. We compare the relation between sophistication and welfare under BM in the two belief settings to emphasize the role of high sophistication and correct belief. We also compare our results with Nash equilibrium analysis.

Robust virtual implementation with almost complete information

Artemov, Kunimoto, and Serrano (2013a,b, henceforth, AKS) study a mechanism design problem where arbitrary restrictions are placed on the set of first-order beliefs of agents. Calling these restrictions Δ, they adopt Δ-rationalizability (Battigalli and Siniscalchi, 2003) and show that Δ-incentivecompatibility and Δ-measurability are necessary and sufficient conditions for robust virtual implementation, which implies that virtual implementation is possible uniformly over all type spaces consistent with Δ-restrictions. By appropriately defining Δ in order to restrict attention to complete information environments and thereafter explicitly modelling the assumption of complete information in the language of type spaces, I re-establish the permissive implementation result of Abreu and Matsushima (1992a). However, AKS need to fix a complete information environment throughout their analysis and therefore does not enable us to ask if robust virtual implementation results are “robust” to the relaxation of the complete information environment. The main result of this paper shows that permissive robust virtual implementation results can be extended to nearby incomplete information environments. I also obtain a tight connection between the class of nearby incomplete information environments considered by this paper and that considered by Oury and Tercieux (2012).

An experimental study of the generalized second price auction

We experimentally investigate the Generalized Second Price (GSP) auction used to sell advertising positions in online search engines. Two contrasting click through rates (CTRs) are studied, under both static complete and dynamic incomplete information settings. Subjects consistently bid above the Vikrey–Clarke–Grove's (VCG) like equilibrium favored in the theoretical literature. However, bidding, at least qualitatively, satisfies the contrasting outcomes predicted under the two CTRs. For both CTRs, outcomes under the static complete information environment are similar to those in later rounds of the dynamic incomplete information environment. This supports the theoretical literature that uses the static complete information model as an approximation to the dynamic incomplete information under which advertising positions are allocated in field settings.

Full implementation in backward induction

In a complete-information environment with two or more players and a finite type space, we show that any truthfully implementable social choice function can be fully implemented in backward induction via a finite perfect-information stochastic mechanism with arbitrarily small transfers.

The Signaling Role of Subsidies

Abstract This paper investigates the effect of monopoly subsidies on entry deterrence. We consider a potential entrant who observes two signals: the subsidy set by the regulator and the output level produced by the incumbent firm. We show that not only a separating equilibrium can be supported, where information about the incumbent’s costs is conveyed to the entrant, but also a pooling equilibrium, where the actions of regulator and incumbent conceal the monopolist’s type, thus deterring entry. We demonstrate that the regulator strategically designs subsidies to facilitate, or hinder, entry deterrence, depending on which outcome yields the largest social welfare. Furthermore, we compare equilibrium welfare relative to two benchmarks: complete-information environments and standard entry-deterrence games where the regulator is absent.

Simple mechanisms and preferences for honesty

We consider full implementation in complete-information environments when agents have an arbitrarily small preference for honesty. We offer a condition called separable punishment and show that when it holds and there are at least two agents, any social choice function can be implemented by a simple mechanism in two rounds of iterated deletion of strictly dominated strategies.

Pricing decision research for TPL considering different logistics service level influencing the market demand

Purpose: With the rapid development of economy and the support of government policy, the development of the logistics industry has become a new economic growth engine. As we all know, the reasonable price of logistics service is the most critical factor for logistics enterprises to win market share and make profit. At the same time, the service level is one of the most important factors which will influence the size of the market share. Therefore, this paper constructs a pricing model considering a situation that the logistics service level affects the market demand. This model helps the enterprises to make scientific decisions. Methodology: To achieve this objective, this paper constructs the TPL service and the pricing decision models based on the game theory. Findings: The conclusion shows that under the situation of independent decision-making, the enterprise which has strong ability of logistics service does not necessarily have a competitive advantage, while pricing equilibrium under the situation of joint decision-making, not only make both sides get more income, but also be conducive to improve the level of service. Research limitations: In this research, there are some assumptions that might affect the accuracy the model such as there are only two TPL enterprises to participate in, and considerations are taken under the condition of complete information environment. These assumptions can be relaxed in the future work. Originality: In this research, logistics service level is taken account into the areas of logistics service pricing, which makes the models more practical and more perfect. And this paper constructs game models based on game theory to make up the limitations of traditional pricing theories in logistics service pricing.

Ex post renegotiation-proof mechanism design

We study what kind of equilibria of which mechanisms are ex post renegotiation-proof (EPRP), i.e., robust against the possibility of ex post renegotiation under a variety of renegotiation procedures, and which social choice functions are EPRP implementable. In complete information environments with two agents only budget balanced Groves allocations are EPRP implementable, while with three or more agents – all ex post efficient allocations are. In environments with independent private values essentially only the budget balanced “Groves in expectations” allocations are EPRP implementable, while with three or more agents and correlated beliefs – all ex post efficient allocations are.

The welfare effect of income tax deductions for losses as insurance: Insured- versus insurer-sided adverse selection

Kaplow (1992) shows in a complete-information environment that allowing income tax deductions for losses as partial insurance is undesirable in the presence of private insurance markets. This paper elaborates on Kaplow's finding by studying two extreme types of asymmetric information structures in private insurance markets: Either the insured or insurers possess superior information. It is shown that our derived result is consistent with Kaplow's if the insured have superior information; however, Kaplow's negative conclusion with respect to the income tax deduction will be overturned if insurers have superior information instead. A policy implication from our finding is that whether or not to allow an income tax deduction for losses needs to be more refined and, specifically, it should be tailored to the “adverse selection” information structures of private insurance.

The private provision of excludable public goods: An inefficiency result

Does voluntary contracting suffice for the efficient provision of excludable public goods? Even in a complete information environment, we find that the answer is negative. The reason is that some agents may profit from not participating at the provision stage, but instead negotiate access ex post.

Spite and Reciprocity in Auctions

The paper presents a complete information model of bidding in second price sealed-bid and ascending-bid (English) auctions, in which potential buyers know the unit valuation of other bidders and may spitefully prefer that their rivals earn a lower surplus. Bidders with spiteful preferences should overbid in equilibrium when they know their rival has a higher value than their own, and bidders with a higher value underbid to reciprocate the spiteful overbidding of the lower value bidders. The model also predicts different bidding behavior in second price as compared to ascending-bid auctions. The paper also presents experimental evidence broadly consistent with the model. In the complete information environment, lower value bidders overbid more than higher value bidders, and they overbid more frequently in the second price auction than in the ascending price auction. Overall, the lower value bidder submits bids that exceed value about half the time. These patterns are not found in the incomplete information environment, consistent with the model.

Efficient Repeated Implementation

This paper examines repeated implementation of a social choice function (SCF) with innitely-lived agents whose preferences are determined randomly in each period. An SCF is repeated-implementable in Nash equilibrium if there exists a sequence of (possibly history-dependent) mechanisms such that (i) its Nash equilibrium set is non-empty and (ii) every Nash equilibrium outcome corresponds to the desired social choice at every possible history of past play and realizations of uncertainty. We show, with minor qualications, that in the complete information environment an SCF is repeated-implementable in Nash equilibrium if and only if it is ecient. We also discuss several extensions of our analysis, including constructions employing only nite mechanisms.

Simple collusive agreements in one-shot first-price auctions

The paper demonstrates that collusion in a private value first price auction is likely to occur even in a one shot interaction. The strategies of the colluding parties must be mixed since agreeing to submit a bid equal to the reservation price of the seller provides the incentive for that bidder to cheat on the designated winner. We deal with a complete information environment with arbitrary number of bidders. We characterize the sensible equilibrium outcome where the two bidders with the highest valuations collude. We show that the equilibrium outcome is unique and that the probability of collusion exceeds 1/2.

Mechanism Design under Alternative Information Structures and Constrained Capacity

In applied models, the choice of a particular incomplete information structure appears to have been motivated primarily by technical convenience. The information structures used can be classified as either probabilistic or partitional. Information is probabilistic if no agent can rule out any type profile of the remaining agents and, for at least one type of one agent, the conditional and marginal probability distributions over the remaining agents' types are not equal. Information is partitional if the only information the agents have is that one or more agents (individually) can rule out type profiles of the remaining agents and, for at least one type of one agent, that agent has information about the remaining agents. Partitional information includes complete information as a special case. Existing results on complete information environments suggest that partitional information might simplify implementation problems. Within the context of an applied agency model in which capacity is constrained, we provide results that seem to challenge this intuition.Journal of Economic LiteratureClassification Numbers: C72, D82.

Exact Implementation

We study implementation of social choice functions when the planner can randomize and impose arbitrarily small fines on players. In complete information environments with three or more players, it is shown that any social choice function is exactly implementable in iteratively weakly undominated strategies. The mechanisms used are finite and robust to the order of removal of dominated strategies. Journal of Economic Literature Classification Numbers: C72, D78, D82.

Bayesian Monotonicity with Side Payments

We investigate Bayesian Nash implementation with side payments. It is familiar that Bayesian monotonicity, together with self selection is necessary and sufficient for full implementation. We introduce an easily verifiable condition, Condition 1, which is equivalent to Bayesian monotonicity under strict self selection. We also introduce an informational condition called the no-consistent-deception condition, which is sufficient for Condition 1. We then show that the no-consistent-deception condition is very weak and conclude that Bayesian monotonicity holds generically. This is in contrast to the well-known negative result for complete information environments. Moreover, we extend virtual implementation to Bayesian environments. Journal of Economic Literature Classification Numbers: 025, 026.

Monopoly Agenda Control and Asymmetric Information

This paper extends the Romer-Rosenthal [1978, 1979] model of monopoly agenda control to an environment where only the agenda setter knows with certainty the outcome associated with a failed proposal. The presence of this asymmetric information implies that any take-it-or-leave-it proposal may provide information crucial to the decision calculus of the voters, a fact which an optimal proposal strategy will incorporate. The equilibrium behavior of the agenda setter and voters is characterized and contrasted with that in the complete information environment, and a number of empirical predictions concerning the nature of elections with monopoly controlled agendas are derived.