Tech Reports

[movellan]

The following technical reports are available online at 
http://mplab.ucsd.edu  (follow links to Tech Reports)


        A Multithreaded Approach to Real Time Face Tracking

          Boris E. Shpungin and Javier R. Movellan 

We present a multithreaded approach to real-time face tracking.  The
system consists of a set of modules running on different processing
threads and coordinated by a mini operating system. The first module
uses color, shape, and face dynamics to determine a 2-D region of
interest.  The second module is a mixture of linear experts classifier
whose task is to help determine whether the region of interest is
indeed a face.
     
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             Active Inference in Concept Induction 

            Jonathan D. Nelson and Javier R. Movellan

People are active information gatherers, constantly experimenting and
seeking information relevant to their goals. A reasonable approach to
active information gathering is to ask questions and conduct experiments
that maximize the expected information gain given our current beliefs
(Lindley, 1956; Good, 1966; MacKay, 1992). In this paper we compare
the behavior of human subjects with that of an optimal
information-gathering agent (infomax) in a concept induction task
(Tennenbaum, 1999). Results show high consistency between subjects in
their information gathering behavior. However infomax generally fails to
predict what subjects do. It is unclear at this point
whether the failure of infomax is due to problems with 
Tennenbaum's concept induction model, or due to the fact that 
subjects use suboptimal heuristics (e.g., confirmatory sampling).