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This paper proposes a game-theoretic model to analyze the strategic behavior of inc-dec gaming in market-based congestion management (redispatch). We extend existing models by considering incomplete information about competitors' costs and a finite set of providers. We find that these extensions do not dissolve inc-dec gaming, which already occurs in our setup of two regions. We also benchmark market-based redispatch against grid investment, cost-based redispatch, and the Vickrey-Clarke-Groves mechanism. The comparison highlights a significant inefficiency of market-based redispatch and inflated redispatch payments. Finally, we study seven variations of our basic model to assess whether different market fundamentals or market design changes mitigate inc-dec gaming. None of these variations eliminate inc-dec gaming entirely.

Das Jahr 2021 hat in Deutschland neuen Schwung in die Bemühungen zum Klimaschutz gebracht. Die Novelle des Klimaschutzgesetzes schreibt eine Reduktion der Treibhausgasemissionen um 65 % bis zum Jahr 2030 gegenüber 1990 fest. Maßgeblich dazu beitragen soll ein massiver Ausbau der Stromerzeugung aus erneuerbaren Energien. Nach Verschärfung der Klimaschutzmaßnahmen stellt sich die Frage, ob das bisherige Strommarktdesign und die damit einhergehenden Vergütungsregeln für die Stromerzeugung auch bei einem von erneuerbaren Energien dominierten Strommarkt weiterhin geeignet sind, um die im Energiewirtschaftsgesetz festgeschriebenen Ziele der Versorgungssicherheit und Preisgünstigkeit bestmöglich zu erreichen. The year 2021 has brought new momentum to climate protection efforts in Germany. The amendment to the Climate Protection Act stipulates a 65 % reduction in greenhouse gas emissions by 2030 compared to 1990. A major contribution to this will come from a massive expansion of electricity generation from renewable energies. Following the tightening of the climate protection measures, the question arises as to whether the current electricity market design and the associated remuneration rules for electricity generation are still suitable for achieving the goals of security of supply and low prices stipulated in the Energy Industry Act, even with an electricity market dominated by renewable energies.

Herdenimmunität, oder zumindest eine hohe Durchimpfung, ist ein Ziel der Impfungen gegen COVID-19. Dieses soll möglichst schnell erreicht werden, um weitere Ansteckungswellen zu verhindern und auch die Ausbreitung stärker ansteckender Varianten zu bremsen. Bisher war die Impfstoffmenge ein limitierender Faktor, der aber zeitnah verschwinden wird, so dass das Impfangebot durch Mediziner und die Impfbereitschaft in der Bevölkerung relevant für die Zielerreichung wird. Die Impfbereitschaft in der Bevölkerung kann jedoch niedriger sein als es für Herdenimmunität notwendig ist. Neben einer generellen Ablehnung einer Impfung ist auch relevant, dass der individuelle Nutzen einer Impfung in der Anzahl der insgesamt Geimpften abnimmt. Insbesondere Menschen mit hohen Transaktionskosten beispielsweise durch unflexible Arbeitszeiten, Betreuungsbedarf für Kinder oder fehlende Transportmittel werden zunächst ungeimpft bleiben. Bisherige Diskussionen konzentrieren sich auf die Nachfrage nach Impfungen, d.h. die Schaffung von Anreizen für potentiell Impfwillige. Es sollte aber auch die Angebotsseite, d.h. die impfenden Mediziner nicht vernachlässigt werden. Aufklärung und Information durch impfende Mediziner ist ein entscheidender Faktor in der Erhöhung der Impfbereitschaft. Allerdings gilt: Je mehr Menschen geimpft sind, desto schwieriger wird es potentiell Impfwillige zu erreichen, aufzuklären und zu impfen. Dadurch steigen die Kosten im Verlauf der Impfkampagne. Impfende Mediziner benötigen eine flexible Kostenerstattung, die an den Aufwand angepasst ist. Ein bedarfsorientiertes Kostenerstattungsschema für Mediziner kann hier Abhilfe schaffen.

Auctions with endogenous rationing have been introduced to stimulate competition. Such (procurement) auctions reduce the volume put out to tender when competition is low. This paper finds a strong negative effect of endogenous rationing on participation when bid-preparation is costly, counteracting the aim to stimulate competition. For multiple auctioneer's objectives mentioned in directives, we derive optimal mechanisms, which differ due to different evaluation of the tradeoff between participation and bid-preparation costs. Thus, the auctioneer needs to decide on an objective. However, reducing bid-preparation costs improves the optimal values of multiple objective functions.

This paper derives Bayesian equilibria under general conditions for a broad family of sealed-bid combinatorial auction formats under incomplete information. Equilibria are constructed by linking an equilibrium of the combinatorial auction format to an equilibrium of its single-unit version, thereby providing a closed-form expression if the single-unit version has one. Auction formats that share the same single-unit version, like the Vickrey auction and all bidder-optimal core-selecting auctions, have common equilibria for any number of items and bidders. Furthermore, if an ex-post equilibrium exists in the single-unit version of an auction then the auction format has an ex-post equilibrium in the combinatorial auction. We characterize the ex-post equilibria for a subfamily of auctions.

We investigate equilibrium bidding behavior of bidders with reference-dependent preferences and independent private values in single-unit English and Dutch clock auctions. Bidders' reference points are endogenous and determined by their strategy and their beliefs about the other bidders. In deriving their strategy, bidders anticipate changes in their reference point due to updated information about others' values (i.e., the own winning probability) during the course of the auction, and make optimal binary decisions at each price (approve or quit in the English auction and wait or bid in the Dutch auction). First, we solve for personal equilibrium profiles, i.e., profiles of bids that contain for each bidder a bidding strategy that is optimal given the others' bidding strategies and the reference point induced by the own and others' strategies. Second, we consider locally preferred personal equilibrium (LPPE) profiles, i.e., personal equilibrium profiles where no bidder can locally find a better personal equilibrium given the others' fixed strategies by varying his reference point via considering different own strategies. The expected revenue in the Dutch auction is higher than in the English auction in the respective unique LPPE profiles. The difference is mainly driven by the aversion to losing the item in the Dutch auction.

We find new equilibria of minimum-revenue core-selecting (MRCS) auctions that, in contrast to previously identified equilibria, involve overbidding - bidding more than one's true value for some packages of goods. With full information, every MRCS auction in every possible setting has equilibria with overbidding and these equilibria have different properties than the previously known equilibria with bid shading. Namely, they can lead to strictly higher revenues for the seller and larger price differences among bidders. Previous studies of MRCS games with incomplete information assumed restricted strategy spaces that prevented overbidding. In this paper, we allow bidders access to their complete strategy sets and show that, in some settings, overbidding occurs in all Bayesian equilibria in undominated strategies. In a simple setting with independent private values, equilibrium strategies of a particular set of MRCS auctions employ a mixture of bid shading and overbidding. These new equilibria improve expected effi ciency relative to equilibria with restricted strategy spaces and lead to higher expected revenues than those from the Vickrey package auction. A second incomplete-information setting demonstrates that equilibria with overbidding can be in some sense unique. In this setting, every Bayesian equilibrium in undominated strategies of every MRCS auction has at least one bidder who overbids and there is no bid shading on winning packages. Overbidding eliminates the threshold problem, leading to an effi cient assignment and payoffs that are in the core with respect to the true values.

We analyze a model of Internet auctions. Sellers each offer one item of a heterogeneous good to bidders who have unit-demand preferences. Items are sold in second-price proxy auctions. We derive a perfect Bayesian (epsilon-) equilibrium. Our experimental findings support the theoretical results. An analysis of sellers' revenues in the Vickrey-auction reveals that they are non-monotonic in bids for substitutes valuations. We combine these results to investigate incomplete bidder-seller networks.

Dissertation, RWTH Aachen University, 2018; Aachen 1 Online-Ressource (85 Seiten) : Illustrationen (2018). = Dissertation, RWTH Aachen University, 2018, The difference between the willingness-to-pay (WTP) and the willingness-to-accept (WTA) has been widely studied and established in the literature. A WTP-WTA disparity is particularly relevant when the agents do not know whether they will be the buyer or the seller of an object, because then they are forced to assess both their WTP and their WTA. This phenomenon occurs in mechanisms to dissolve a partnership, i.e., an indivisible object that is jointly owned by more than one agent. Agents do not know ex-ante whether they will be buying the shares of other agents or selling their own share. Dissolution mechanisms decide which agent is to be awarded the partnership and how the others are to be compensated. The first section of this dissertation identifies a necessary and sufficient condition for the existence of an efficient dissolution mechanism in an independent private values model. In our setup – in contrast to the standard case, where the WTP and the WTA coincide – the existence of such a mechanism cannot be guaranteed. The second section analyzes a dissolution mechanism that is used in practice and is known to be efficient if there is no difference between the WTP and the WTA: the k+1-price auction. We show that even for an arbitrarily small difference between the WTP and the WTA, the k+1-price auction is inefficient. In addition, if the difference exceeds a certain threshold, agents are not willing to participate in the auction. Because of that, we analyze variations of the k+1-price auction which guarantee voluntary participation. The last section provides an experimental analysis of the performance of (combinatorial) core-selecting and Vickrey auctions. It contributes to the literature by explicitly testing equilibrium predictions under the realistic assumption of incomplete information. In the experiment, the proportion of efficient assignments is high for all auctions. The core-selecting auction performs better than the combinatorial Vickrey auction in generating revenue and in selecting stable (core) allocations. Interestingly, in an independent private values setting, the core-selecting auction is predicted to select fewer (eponymous) core allocations than the Vickrey auction and the data point in the opposite direction. The core-selecting auction provides incentives for overbidding the own valuation and – under certain conditions – also for bid-shading, which can hamper performance. The participants react to these incentives, though less pronouncedly than predicted., Published by Aachen