Due to compliance and IT security requirements, company-wide identity and access management within organizations has gained significant importance in research and practice over the last years. Companies aim at standardizing user management policies in order to reduce administrative overhead and strengthen IT security. These policies provide the foundation for every identity and access managemen...

(DGAs) constitute an interesting approach to undertake the premature convergence problem in evolutionary optimization. This is done by spatial partitioning a huge panmitic population into several semi-isolated groups, called demes, each evolving in parallel by its own pace, and possibly exploring different regions of the search space. At the center of such approach lies the migratory process th...

Solving stochastic optimization problems under partial observability, where one needs to adaptively make decisions with uncertain outcomes, is a fundamental but notoriously difficult challenge. In this paper, we introduce the concept of adaptive submodularity, generalizing submodular set functions to adaptive policies. We prove that if a problem satisfies this property, a simple adaptive greedy...

In this paper, we propose a hierarchical architecture of server network for supporting a large-scale TV-Anytime system. We present and formulate various policies used for the effective mapping of videos in the runtime of the TV-Anytime system. A predictive assignment policy is presented to periodically determine the mapping of videos to the server network. Furthermore, we present an adaptive re...

Mobile computers typically spin down their hard disk after a fixed period of inactivity. If this threshold is too long, the disk wastes energy; if it is too short, the delay due to spinning the disk up again frushates the user. Usage patterns change over time, so a single fixed threshold may not be appropriate at all times. Also, different users may have varying priorities with respect to tradi...

Mitigating risk in decision-making has been a longstanding problem. Due to the mathematical challenge of its nonlinear nature, especially in adaptive decisionmaking problems, finding optimal policies is typically intractable. With a focus on efficient algorithms, we ask how well we can approximate the optimal policies for the difficult case of general utility models of risk. Little is known abo...

We study experiments of an overlapping generations model where inflation is determined by the monetary policy and by the amount of average saving within each period. We use a new experimental setup that allows us to observe more details of the process of expectation forming and separate this process from the actual saving process. In contrast to experimental findings by Lim, Prescott, Sunder; M...

Gossipping has demonstrate to be an efficient mechanism for spreading information among P2P networks. Within the context of P2P computing, we propose the so-called Evolvable Agent Model for distributed population-based algorithms which uses gossipping as communication policy, and represents every individual as a self-scheduled single thread. The model avoids obsolete nodes in the population by ...