"Is it better to force the user to give feedback on five crucial search results? Or should you show 50 results and have the user cherry pick results that are particularly good/bad?"
What metafore are you trying to support? Is the system one that learns (think child) or one that adapts (adult).
If you present a system as one that needs to be taught you will invoke a whole different set of expectations than one where it is assumed to know a great deal but can adapt.
Personally I always recommend forcing a user to teach the system (see Netflix new user flow) because it breaks the assumption that the system will 'just know' which is often unreasonable.
What metafore are you trying to support? Is the system one that learns (think child) or one that adapts (adult).
If you present a system as one that needs to be taught you will invoke a whole different set of expectations than one where it is assumed to know a great deal but can adapt.
Personally I always recommend forcing a user to teach the system (see Netflix new user flow) because it breaks the assumption that the system will 'just know' which is often unreasonable.