Great. Thanks, Ted! --Jamey
On Wed, Jul 20, 2011 at 9:57 PM, Ted Dunning <[email protected]> wrote: > Oh... you do have to be careful with this a bit because some of these side > factors can have disastrously non-sparse characteristics. For instance, a > large fraction of the people in the world are in each age range. Likewise, > there are entirely too many romance novels in the world. These issues of > prevalence can seriously impact your algorithm run-time (adversely). You > can compensate for this by sampling or just recognizing that such pervasive > features inherently cannot be very useful since too many things would be > recommended. > > On Wed, Jul 20, 2011 at 8:51 PM, Ted Dunning <[email protected]> > wrote: > > > Yes. This can work. And it can go both ways since you might do > something > > like combine recommendations for a specific book with more general > > recommendations for a specific author or genre. You can also have > > recommendations for, say, an author or genre based on demographic > quantities > > such as geo-location or age range. > > > > It can be a bit tricky to combine all of these features. One principled > > way would be to extend the log-linear latent factor approach to include > > these multiple cross terms. A less principled, but pretty effective > method > > is to score all kinds of recommendations independently and then > recalibrate > > based on percentiles (if you can make sense of that, often not possible) > or > > by some declining function of rank. > > > > > > On Wed, Jul 20, 2011 at 7:18 PM, Jamey Wood <[email protected]> > wrote: > > > >> Is there any precedent for treating users' demographic characteristics > as > >> items (particularly for item-based recommendation)? For example, if one > >> were performing item-based recommendation within a bookselling site, > it'd > >> be > >> natural to include the user:item purchases as boolean preferences. But > >> could it also make sense to include certain user:demographic pairs as > >> boolean preferences (e.g. user123:age40-to-50)? Of course, these items > >> would need to be filtered (by a Rescorer) in the recommendation outputs, > >> but > >> I'm curious whether including them as inputs is potentially helpful. > >> > >> Thanks, > >> Jamey > >> > > > > >
