Task Decomposition Through Competition in a Modular Connectionist Architecture: The What and Where Vision Tasks

TLDR

Function decomposition is underconstrained, but restricting the types of functions a modular architecture can compute—leveraging its domain‑knowledge‑friendly structure—can yield desirable decompositions. The study introduces a modular connectionist architecture in which competing networks learn training patterns, and demonstrates that domain knowledge can guide the selection of appropriate functional restrictions. The architecture decomposes a task by partitioning it into functionally independent subtasks, assigning each to a distinct network and favoring the network whose topology best matches the subtask. The competition drives specialization, producing distinct functions, and the architecture achieves superior performance on the what and where vision tasks relative to two multilayer networks.

Abstract

A novel modular connectionist architecture is presented in which the networks composing the architecture compete to learn the training patterns. An outcome of the competition is that different networks learn different training patterns and, thus, learn to compute different functions. The architecture performs task decomposition in the sense that it learns to partition a task into two or more functionally independent tasks and allocates distinct networks to learn each task. In addition, the architecture tends to allocate to each task the network whose topology is most appropriate to that task. The architecture's performance on “what” and “where” vision tasks is presented and compared with the performance of two multilayer networks. Finally, it is noted that function decomposition is an underconstrained problem, and, thus, different modular architectures may decompose a function in different ways. A desirable decomposition can be achieved if the architecture is suitably restricted in the types of functions that it can compute. Finding appropriate restrictions is possible through the application of domain knowledge. A strength of the modular architecture is that its structure is well suited for incorporating domain knowledge.