Abstract-The classical approach to using utility functions suffers from the drawback of having to design and tweak the functions on a case by case basis. Inspired by examples from the animal kingdom, social sciences and games we propose empowerment, a rather universal function, defined as the information-theoretic capacity of an agent's actuation channel. The concept applies to any sensorimotor apparatus. Empowerment as a measure reflects the properties of the apparatus as long as they are observable due to the coupling of sensors and actuators via the environment. Using two simple experiments we also demonstrate how empowerment influences sensor-actuator evolution.

In the present study we investigated humanrobot and robot-human approach distances. We found that subjects' personality profiles influence personal spatial zones in human-robot interaction experiments. We tested two hypotheses: First, we predicted that approach distances preferred by humans when interacting with a robot would be comparable to those preferred when humans interact socially with each other. Our experiments involving humans interacting with a mobile robot confirm this hypothesis. However, surprisingly, a large minority of subjects in the experiments took up positions which were significantly closer, suggesting that they were not treating the robot as a 'social entity'. We then tested the hypothesis that common personality factors exist which could be used to predict subjects' likely approach distance preferences. The subjects' personalities were assessed using several traits from the threefactor Eysenck personality model. Further analysis of the data identified four new factors, different from Eysenck's model, tentatively labeled "Proactiveness", "Social Reluctance", "Timidity" and "Nervousness". When testing for correlations between approach distances and personality data, "Proactiveness" correlates with social distance, i.e. subjects that score higher on this factor come less close to the robot. We discuss the potential suitability of personality factors to predict approach distances in human-robot interaction experiments.

???The original publication is available at www.springerlink.com???. Copyright Springer. [Full text of this article is not available in the UHRA]The Cognitive Dimensions of Notations framework has been created to assist the designers of notational systems and information artifacts to evaluate their designs with respect to the impact that they will have on the users of those designs. The framework emphasizes the design choices available to such designers, including characterization of the user???s activity, and the inevitable tradeoffs that will occur between potential design options. The resulting framework has been under development for over 10 years, and now has an active community of researchers devoted to it. This paper first introduces Cognitive Dimensions. It then summarizes the current activity, especially the results of a one-day workshop devoted to Cognitive Dimensions in December 2000, and reviews the ways in which it applies to the field of Cognitive Technology

The central resource processed by the sensorimotor system of an organism is information. We propose an information-based quantity that allows one to characterize the efficiency of the perception-action loop of an abstract organism model. It measures the potential of the organism to imprint information on the environment via its actuators in a way that can be recaptured by its sensors, essentially quantifying the options available and visible to the organism. Various scenarios suggest that such a quantity could identify the preferred direction of evolution or adaptation of the sensorimotor loop of organisms.

The original publication is available at www.springerlink.com . Copyright Springer DOI : 10.1007/11553090_75The classical approach to using utility functions suffers from the drawback of having to design and tweak the functions on a case by case basis. Inspired by examples from the animal kingdom, social sciences and games we propose empowerment, a rather universal function, defined as the information-theoretic capacity of an agent???s actuation channel. The concept applies to any sensorimotoric apparatus. Empowerment as a measure reflects the properties of the apparatus as long as they are observable due to the coupling of sensors and actuators via the environment