Olivier Georgeon's research blog—also known as the story of little Ernest, the developmental agent.

Keywords: situated cognition, constructivist learning, intrinsic motivation, bottom-up self-programming, individuation, theory of enaction, developmental learning, artificial sense-making, biologically inspired cognitive architectures, agnostic agents (without ontological assumptions about the environment).

Friday, October 31, 2008

Ernest's viewpoint on his activity

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Learning second-order schemas from activity is is not so easy. To get insights, I have slightly modified Ernest and displayed his activity trace under a new form.

Newly released Ernest 3.1 implements the same strategy as Ernest 3.0 in the same "aA..bB..aA..aA" environment. His trace, however, does not print his primary actions but his primary schemas. So, instead of just selecting an action from previous experience, Ernest 3.1 constructs a full proposed schema. The trace prints this proposed schema (in orange) when it is enacted. The weights that led Ernest to choose this schema are printed in parenthesis in the same line. In addition, instead of printing the environment's response (Y or X), this trace prints the schemas that Ernest learns (in blue) when the interaction cycle is completed.

When weights for doing a A- or a B-schema are equal, Ernest chooses randomly and expresses his hesitation by "Hum?". If a randomly-chosen schema succeeds, Ernest expresses his satisfaction by "Yee!"; if it fails, Ernest expresses his deception by "Boo.". In both cases, the actual schema is learned or reinforced.

When weights for doing a A- or a B-schema are different, then Ernest proposes a schema based on the highest one. In that case, he is confident of getting Y, and he expresses this confidence by "Hop!". If the schema succeeds he says "A-a", but if the schema fails, he expresses his surprise by "O-o".

This new trace layout is interesting because we can understand it as the Ernest's viewpoint on his activity. His activity appears to him as a stream of "affordances", i.e., a stream of contexts that trigger schemas.

Moreover, the schemas that Ernest learns from his activity are shown in the trace (in blue). These schemas constitute knowledge that Ernest can use to fulfill his goal of getting Ys. Hence, we can consider that Ernest "understands" these schemas, if we agree with a pragmatic epistemology stating that "meaning just is use" (Wittgenstein, 1953). From this first layer of knowledge, Ernest should construct more abstract knowledge that stays meaningful to him because this knowldege stays grounded on Ernest's activity.

Reference

Wittgenstein, Ludwig (1953/2001). Philosophical Investigations.

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