The information transfer can also be interpreted as the acquisition of information from the environment by a single adapting individual: there is evidence that pushing the information flow to the information-theoretic limit (i.e. maximization of information transfer) can give rise to intricate behaviour, induce a necessary structure in the system, and ultimately adaptively reshape the system [1-3]. The central hypothesis of Klyubin et al. is that there exists "a local and universal utility function which may help individuals survive and hence speed up evolution by making the fitness landscape smoother", while adapting to morphology and ecological niche. The proposed general utility function, empowerment, couples the agent’s sensors and actuators via the environment. Empowerment is the perceived amount of influence or control the agent has over the world, and can be seen as the agent’s potential to change the world. It can be measured via the amount of Shannon information that the agent can "inject into" its sensor through the environment, a effecting future actions and future perceptions. Such a perception-action loop defines the agent’s actuation channel, and technically empowerment is defined as the capacity of this actuation channel: the maximum mutual information for the channel over all possible distributions of the transmitted signal. "The more of the information can be made to appear in the sensor, the more control or influence the agent has over its sensor" – this is the main motivation for this local and universal utility function .
1. Klyubin, A.S., Polani, D. and Nehaniv, C.L. Organization of the information flow in the perception-action loop of evolved agents. In Proceedings of 2004 NASA/DoD Conference on Evolvable Hardware, page 177-180. IEEE Computer Society, 2004.
2. Klyubin, A.S., Polani, D. and Nehaniv, C.L. All else being equal be empowered. In M. S. Capcarr‘ere, A. A. Freitas, P. J. Bentley, C. G. Johnson, and J. Timmis, editors, Advances in Artificial Life, 8th European Conference, ECAL 2005, volume 3630 of LNCS, page 744-753. Springer, 2005.
3. Klyubin, A.S., Polani, D. and Nehaniv, C.L. Empowerment: A Universal Agent-Centric Measure of Control. In Proc. CEC 2005. IEEE.
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.