Trusted Third Parties in the Electronic Marketplace: An Evolutionary Game Approach

Using an evolutionary game approach, this paper studies different equilibria in the electronic marketplace, and demonstrates that electronic transaction through a TTP is an evolutionarily stable strategy. According to the evolutionary game analysis, people will gradually adopt this strategy in the electronic marketplace

Skorohod's representation theorem for sets of probabilities

Dumav M, Stinchcombe MB. Skorohod's representation theorem for sets of probabilities. Center for Mathematical Economics Working Papers. Vol 481. Bielefeld: Center for Mathematical Economics; 2013

The von Neumann/Morgenstern approach to ambiguity

Dumav M, Stinchcombe MB. The von Neumann/Morgenstern approach to ambiguity. Center for Mathematical Economics Working Papers. Vol 480. Bielefeld: Center for Mathematical Economics; 2013.A choice problem is risky (respectively ambiguous) if the decision maker is choosing between probability distributions (respectively sets of probability distributions) over utility relevant consequences. We provide an axiomatic foundation for and a representation of continuous linear preferences over sets of probabilities on consequences. The representation theory delivers: first and second order dominance for ambiguous problems; a utility interval based dominance relation that distinguishes between sources of uncertainty; a complete theory of updating convex sets of priors; a Bayesian theory of the value of ambiguous information structures; complete separations of attitudes toward risk and ambiguity; and new classes of preferences that allow decreasing relative ambiguity aversion and thereby rationalize recent challenges to many of the extant multiple prior models of ambiguity aversion. We also characterize a property of sets of priors, descriptive completeness, that resolves several open problems and allows multiple prior models to model as large a class of problems as the continuous linear preferences presented here

Neural network representation and learning of mappings and their derivatives

Discussed here are recent theorems proving that artificial neural networks are capable of approximating an arbitrary mapping and its derivatives as accurately as desired. This fact forms the basis for further results establishing the learnability of the desired approximations, using results from non-parametric statistics. These results have potential applications in robotics, chaotic dynamics, control, and sensitivity analysis. An example involving learning the transfer function and its derivatives for a chaotic map is discussed

Torture in Counterterrorism: Agency Incentives and Slippery Slopes

Abstract We develop a model of counterterrorism to analyze the effects of allowing a government agency to torture terrorist suspects. We find that legalizing torture in high evidence cases has offsetting effects on agency incentives to counter terrorism by means other than torture. It increases these incentives because other efforts may increase the probability of having high enough evidence to warrant the use of torture if other efforts fail. However, it also lowers these incentives because the agency might come to rely on torture to avert attacks. If the latter effect dominates, legalizing torture in high evidence cases can reduce security and increase the probability of terrorist attack. Moreover, it can increase agency incentives to torture even in low evidence cases, leading to a "slippery slope." (JEL K4, D8, H1

Populist Mobilization: A New Theoretical Approach to Populism*

Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/112280/1/j.1467-9558.2011.01388.x.pd

University spin-off's performance: Capabilities and networks of founding teams at creation phase

The extant literature highlights that environmental conditions, during the creation phase, imprint on a start-up’s survival and growth. However, there are few studies that explore the composite nature of a founding team’s capabilities and networks, developed within this phase, and the contribution made to future performance. This paper uses the distinctive context of university spin-offs, where early stage ventures are fostered by institutional interventions, to analyse the influence that the capabilities and networks of a founding team, at incorporation, have upon the future performance of the spin-off. Based on data from 181 university spin-offs, this paper empirically demonstrates that the entrepreneurial capabilities of a founding team, augmented during the ‘creation’ phase, have a positive influence on the performance of a spin-off during the ‘growth’ phase, and that the networks of a founding team indirectly affect a spin-off’s performance through the enhancement of a team’s entrepreneurial capabilities

More on the multivariate Helly theorem

International audienceThis paper presents an alternative and more general proof of Helly's selection theorem than that presented in [2]. The proof and the ensuing discussion make clear the role of local compactness in determining the crucial properties of the topology of vague convergence