Note on Generalisation in ANNs

This note is relevant to both the Assessed Coursework and to the (related) Programming exercise for seminars in week 4.

In both these cases, the training set should include every possible pattern of 0s and 1s. Because these Boolean input patterns are all so different from each other, with no common pattern, you should not expect generalisation; ie if you train on a subset and hope for generalisation to unseen test cases, you will probably be disappointed.

This is in contrast to the discussion in Lectures, eg Lec 7, where we considered case where generalisation is possible. Eg with a training set of  pictures of dogs, one can reasonably expect a common theme to exist, so that an ANN, properly trained, could generalise to an unseen test picture. But with the Boolean inputs of the Assessed Coursework (and the seminar exercise), this is not the case - these are generalisation-unfriendly types of problems.