Summary. The first part is the study of several conditions which are sufficient for the coincidence of the prenucleolus concept and the egalitarian nonseparable contribution (ENSC-) method. The main sufficient condition for the coincidence involved requires that the maximal excesses at the ENSC-solution are determined by the (n-1)-person coalitions in the n-person game. The second part is the study of both a new type of games, the so-called kcoalitional n-person games, and the interrelationship between solutions on the class of those games. The main results state that the Shapley value of a k-coalitional nperson game can be written as a convex or affine combination of the ENSC-solution and the centre of the imputation set.Zusammenfassung. Im ersten Teil der Arbeit werden verschiedene hinreichende Bedingungen fiir die Koinzidenz des Prenukleolus-L6sungskonzepts und der ENSCRegel vorgestellt. Es wird dabei gezeigt, dab der Prenukleolus mit der ENSC-L6sung zusammenf~illt, falls die maximalen Exzesse der ENSC-L6sung durch die (n-1)-Personen Koalitionen des n-Personenspiels bestimmt werden. Im zweiten Teil der Arbeit untersuchen wir eine Klasse yon Spielen, die sogenannten k-Koalitions-n-Personenspiele und untersuchen die Zusammenh~inge zwischen den LSsungskonzepten ffir diesen speziellen Typ yon Spielen. Es stellt sich heraus, dab der Shapleywert eines k-Koalitions-n-Personenspiels beschrieben werden kann als eine Linearkombination der ENSC-L6sung und des Schwerpunktes der Auszahlungsmenge.

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ABSTRACT. A situation, in which a finite set of players can obtain certain payoffs by cooperation can be described by a cooperative game with transferable utility, or simply a TU-game. A (point-valued) solution for TU-games assigns a payoff distribution to every TU-game. In this article we discuss a class of equal surplus sharing solutions consisting of all convex combinations of the CIS-value, the ENSC-value and the equal division solution. We provide several characterizations of this class of solutions on variable and fixed player set. Specifications of several properties characterize specific solutions in this class.

One of the main issues in economic allocation problems is the trade-off between marginalism and egalitarianism. In the context of cooperative games this trade-off can be framed as one of choosing to allocate according to the Shapley value or the equal division solution. In this paper we provide three different characterizations of egalitarian Shapley values being convex combinations of the Shapley value and the equal division solution. First, from the perspective of a variable player set, we show that all these solutions satisfy the same reduced game consistency. Second, on a fixed player set, we characterize this class of solutions using monotonicity properties. Finally, towards a strategic foundation, we provide a non-cooperative implementation for these solutions which only differ in the probability of breakdown at a certain stage of the game. These characterizations discover fundamental differences as well as intriguing connections between marginalism and egalitarianism. R. van den Brink (B)

We experimentally investigate the effect of a central bank buying bonds for cash in a quantitative easing (QE) operation. In our experiment, the bonds are perfect substitute for cash, and have a constant fundamental value (FV) which is not affected by QE in the rational expectations equilibrium. We found that QE raised the bond prices beyond those in the benchmark treatment without QE and these differences became larger as subjects gained experience. While subjects in the benchmark treatment learned to trade the bonds at its FV, those in treatments with QE became more convinced that QE boosts bond prices.