This paper presents a method to quantitatively evaluate
information contributions of individual bottom-up and topdown
computing processes in object recognition. Our objective
is to start a discovery on how to schedule bottomup
and top-down processes. (1) We identify two bottom-up
processes and one top-down process in hierarchical models,
termed α, β and γ channels respectively ; (2) We formulate
the three channels under an unified Bayesian framework;
(3) We use a blocking control strategy to isolate the
three channels to separately train them and individually
measure their information contributions in typical recognition
tasks; (4) Based on the evaluated results, we integrate
the three channels to detect objects with performance improvements
obtained. Our experiments are performed in
both low-middle level tasks, such as detecting edges/bars
and junctions, and high level tasks, such as detecting human
faces and cars, together with a group of human study
designed to c...