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From Jake Mannix <jake.man...@gmail.com>
Subject Re: Feedback on provided recommendations
Date Tue, 27 Apr 2010 19:55:39 GMT
Well you could always regress on the blending coefficient, and let your data
tell you whether it should be positive or negative. :)

On Tue, Apr 27, 2010 at 12:53 PM, Ted Dunning <ted.dunning@gmail.com> wrote:

> This is also very dangerous because negative ratings often correlated much
> more tightly with what people like than with what they don't like.  If the
> blending is done carelessly, you can wind up recommending everything except
> what the user likes (if the negative ratings overwhelm the positive in
> spite
> of the blending parameters) or you can wind up missing some very good
> stuff.
>
> On Tue, Apr 27, 2010 at 12:46 PM, Jake Mannix <jake.mannix@gmail.com>
> wrote:
>
> > Another approach would be, if you have a lot of negative feedback as well
> > as positive feedback, to train two models, both treating the feedback as
> > positive,
> > and then blend the results with a negative blending weight (i.e. subtract
> > off a
> > scaled multiple of the negative feedback recommendation score from the
> > positive feedback recommendation score).
> >
> > This would only work if you had enough negative feedback to build an full
> > model out of it.
> >
> >  -jake
> >
> > On Tue, Apr 27, 2010 at 11:43 AM, Ted Dunning <ted.dunning@gmail.com>
> > wrote:
> >
> > > Boolean recommendations makes the assumption that either negative
> > feedback
> > > is really positive feedback (controversial, but works reasonably) or
> that
> > > negative feedback is not very useful (also controversial, but actually
> > > generally true).
> > >
> > > If you really want to use negative information soundly, you need to use
> a
> > > much fancier algorithm.  This can lead to huge costs in CPU and memory
> > and
> > > it may or may not help you.  More practical is to use boolean
> > > recommendations for the positive side and then just add a few
> heuristics
> > > for
> > > the negative side.  Typical heuristics include:
> > >
> > >  - don't show items that a user has negatively rated (obviously)
> > >  - don't show items from a source that the user has rated negatively
> > > several times without rating other items from that source positively
> > >
> > >
> > > On Tue, Apr 27, 2010 at 10:27 AM, Tolga Oral <tolga.oral@gmail.com>
> > wrote:
> > >
> > > > We are building a system on top of provided recommendations allowing
> > user
> > > > to
> > > > provide feedback. I have a question on how to apply the negative
> > feedback
> > > > for both boolean and none boolean scores.
> > > >
> > > > Assuming its a boolean item (item with no score), I cant see how we
> can
> > > > provide negative feedback for a given recommendation. Does this mean
> we
> > > > should convert our boolean items to a score of 1 and give score of -1
> > (or
> > > > 0)
> > > > for recommendations that user didnt like?
> > > >
> > > > This applies to items with score too I am not sure if the correct way
> > of
> > > > going about this is to provide 0 or a negative value.
> > > >
> > > > Thank you.
> > > >
> > >
> >
>

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