Programming by demonstration

In the case of programming by demonstration, the user provides feedback for an article that was not retrieved by any of the profiles. When feedback is received for such a document , not retrieved by any of the profiles, the agent has two choices. It can either create a new profile to accept feedback about , or it can direct the feedback to one of the existing profiles.

If there exists a profile , which already retrieves articles from the same newsgroup as the one that belongs to, then the feedback is directed towards . The justification is that, since belongs to a domain already searched by , it is the profile which can benefit the most from receiving the feedback. This results in the modification of , just as if had retrieved the document itself. The only difference from equation is that the learning rate would be higher in the case of programming by demonstration, since the user took special efforts to personally seek out examples of articles.

However, if there is no such profile which meets the above requirement, an empty profile is created and is then given feedback as if it had retrieved document . This effectively creates a profile which looks like . The change in fitness is as shown in equation .