178,872 research outputs found
Coalition formation in simple Games. the semistrict core
No full textDimitrov D, Haake C-J. Coalition formation in simple Games. the semistrict core. Working Papers. Institute of Mathematical Economics. Vol 378. Bielefeld: Universität Bielefeld; 2006.We consider the class of proper monotonic simple games and study coalition formation when an exogenous share vector and a solution concept are combined to guide the distribution of coalitional worth. Using a multiplicative composite solution, we induce players' preferences over coalitions in a hedonic game, and present conditions under which the semistrict core of the game is nonempty
Dividing by Demanding: Object Division through Market Procedures
No full textHaake C-J. Dividing by Demanding: Object Division through Market Procedures. Working Papers. Institute of Mathematical Economics. Vol 359. Bielefeld: Universität Bielefeld; 2004.We discuss a model, in which two agents may distribute finitely many objects among themselves. The conflict is resolved by means of a market procedure. Depending on the specifications, this procedure serves to implement bargaining solutions such as the discrete Raiffa solution, the Kalai-Smorodinsky solution and the Perles-Maschler solution. The latter is axiomatized using the superadditivity axiom, which in the present context is readily interpreted as resolving a specific source of conflict potential
Two support results for the Kalai-Smorodinsky solution in small object division markets
No full textHaake C-J. Two support results for the Kalai-Smorodinsky solution in small object division markets. Working Papers. Institute of Mathematical Economics. Vol 366. Bielefeld: Universität Bielefeld; 2005.We discuss two support results for the Kalai-Smorodinsky bargaining solution in the context of an object division problem involving two agents. Allocations of objects resulting from strategic interaction are obtained as a demand vector in a specific market. For the first support result games in strategic form are derived that exhibit a unique Nash equilibrium. The second result uses subgame perfect equlibria of a game in extensive form. Although there may be multiple equilibria, coordination problems can be removed
Stability and Nash implementation in matching markets with couples
No full textHaake C-J, Klaus B. Stability and Nash implementation in matching markets with couples. Working Papers. Institute of Mathematical Economics. Vol 399. Bielefeld: Universität Bielefeld; 2008.We consider two-sided matching markets with couples. First, we extend a result by Klaus and Klijn (2005, Theorem 3.3) and show that for any weakly responsive couples market there always exists a "double stable" matching, i.e., a matching that is stable for the couples market and for any associated singles market. Second, we show that for weakly responsive couples markets the associated stable correspondence is (Maskin) monotonic and Nash implementable. In contrast, the correspondence that assigns all double stable matchings is neither monotonic nor Nash implementable
Appropriate Similarity Measures for Author Cocitation Analysis
No full textWe provide a number of new insights into the methodological discussion about author cocitation analysis. We first argue that the use of the Pearson correlation for measuring the similarity between authors’ cocitation profiles is not very satisfactory. We then discuss what kind of similarity measures may be used as an alternative to the Pearson correlation. We consider three similarity measures in particular. One is the well-known cosine. The other two similarity measures have not been used before in the bibliometric literature. Finally, we show by means of an example that our findings have a high practical relevance.information science;Pearson correlation;cosine;similarity measure;author cocitation analysis
On Maskin monotonicity of solution based social choice rules
No full textHaake C-J, Trockel W. On Maskin monotonicity of solution based social choice rules. Working Papers. Institute of Mathematical Economics. Vol 393. Bielefeld: Universität Bielefeld; 2007.Howard (1992) argues that the Nash bargaining solution is not Nash implementable, as it does not satisfy Maskin monotonicity. His arguments can be extended to other bargaining solutions as well. However, by defining a social choice correspondence that is based on the solution rather than on its realizations, one can overcome this shortcoming. We even show that such correspondences satisfy a stronger version of monotonicity that is even sufficient for Nash implementability
Addressing Interoperability in Open Hypermedia: the Design of the Open Hypermedia Protocol
No full textComparison of standard and oversize tennis balls for normal impacts on a racket
No full textThe coefficient of restitution was determined for two different types of oversize tennis ball for normal impacts on a rigidly clamped racket. A standard ball was also tested as a control. It was found that an oversize ball with the same mass and type of rubber and internal pressure as a standard ball, rebound with a higher coefficient of restitution. However, an oversize ball with a lower internal pressure rebound with a lower coefficient of restitution, compared to the standard ball. The quasi-static hysteresis loss of balls, determined from compression tests, correlated with the coefficient of restitution results. It was found that an increase of 7% in the ball-racket contact area resulted in a decrease of 5% in maximum string extension, for an impact with the same peak force
'Feel' in relation to the dynamic characteristics of tennis balls
No full textThe quantification of 'feel' in any sport is a difficult objective to obtain because of the number of variables involved. Previous researchers have considered vibration, sound frequency, visual information and force. This paper attempts to define the feel of tennis balls using the coefficient of restitution and contact time on a hard surface. Six types of tennis balls impacted with a force platform at velocities between 2 and 30 ms-1 (5 and 67mph) and the impact and rebound speeds recorded using light gates. The coefficient of restitution decreased with velocity for all balls and the removal of internal air pressure for a pressurised tennis ball reduced the coefficient of restitution by approximately 20% at typical ball racket velocities. The duration of impact was also found to decrease with impact velocity and the removal of internal air pressure caused the contact time to lengthen by 15%. An objective method of measuring the 'feel' of tennis balls was suggested as a combined plot of the 'dynamic' stiffness versus the coefficient of restitution. In comparison to a standard pressured ball, 'better feel' was defined as a ball with a higher dynamic stiffness and with a higher coefficient of restitution. It was found that a punctured ball had much worse 'feel' and only one ball had a better 'feel' than the pressurised ball. It was concluded that this method gave intuitively correct results which need verifying through player testing
"Closing the R&D Gap, Evaluating the Sources of R&D Spending"
No full textBoth spending and tax policies have been implemented in the United States with the goal of stimulating private sector research and development (R&D). Karier questions whether current R&D policy, especially the research and experimentation tax credit, can contribute to closing the gap between nondefense expenditures on R&D in the United States and such expenditures in other countries, such as Japan and Germany. He also explores possible changes to our current R&D policy to make it more effective.
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