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From Ted Dunning <ted.dunn...@gmail.com>
Subject Re: Boolean preferences and evaluation
Date Wed, 23 Jan 2013 21:49:01 GMT
LLR should not be used to indicate proximity, but rather simply as a value
to compare to a threshold.

On Thu, Jan 24, 2013 at 1:45 AM, Zia mel <ziad.kamel25@gmail.com> wrote:

> OK .  The TanimotoCoefficientSimilarity and LogLikelihoodSimilarity
> used in MIA page 54 and 55 provide a score, so it seems they were not
> using a Boolean recommender , something like code 1 maybe? Thanks
>
> On Tue, Jan 22, 2013 at 10:42 AM, Sean Owen <srowen@gmail.com> wrote:
> > Yes any metric that concerns estimated value vs real value can't be
> > used since all values are 1. Yes, when you use the non-boolean version
> > with boolean data you always get 1. When you use the boolean version
> > with boolean data you will get nonsense since the output of this
> > recommender is not an estimated rating at all.
> >
> > On Tue, Jan 22, 2013 at 4:40 PM, Zia mel <ziad.kamel25@gmail.com> wrote:
> >> I got 0 when I used GenericUserBasedRecommender in code 2 but when
> >> using GenericBooleanPrefUserBasedRecommender score was not 0 . I
> >> repeat the test with different data and again I got some results.
> >> Moreover , when I use
> >>      DataModel model = new FileDataModel(new File("ua.base"));
> >> in code 2, the MAE score was higher.
> >>
> >> When you say RMSE can't be used with boolean data, I assume MAE also
> >> can't be used?
> >>
> >> Thanks !
> >>
> >> On Tue, Jan 22, 2013 at 10:08 AM, Sean Owen <srowen@gmail.com> wrote:
> >>> RMSE can't
> >>> be used with boolean data.
>

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