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From Niklas Ekvall <niklas.ekv...@gmail.com>
Subject Re: Question about spark-itemsimilarity
Date Tue, 13 Dec 2016 15:04:01 GMT
Thanks Pat for that information!

I was meant to handle number of clicks or number of downloads and not
rating. But this is not a problem if the Spark doesn't handle values, I
have other algorithms who can handle that. How ever, I am quite curios
about the occurrences, cooccurrences, and cross-occurrences concept.

Can the following be a way to handle different data types?

   - occurrences - purchase history
   - cooccurrences - purchase history/likes
   - cross-occurrences - purchase history/clicks or downloads

Best, Niklas

2016-12-01 18:47 GMT+01:00 Pat Ferrel <pat@occamsmachete.com>:

> No you can’t, the value is ignored. The algorithm looks at occurrences,
> cooccurrences, and cross-occurrences of several event types not values
> attached to events.
>
> If you are trying to use rating info, this has been pretty much discarded
> as being not very useful. For instance you may like comedy movies but they
> always get lower ratings than drama (raters bias) so using ratings to
> recommend items is highly problematic, but if a user watched a movie, that
> is a good indicator that they liked it and that is a boolean value. With
> cross-occurrence you can also use dislike as an indicator of preference but
> this is also boolean—a thumbs down.
>
> To see an end-to-end recommender with all the necessary surrounding
> infrastructure check the Apache-PredictionIO project and the Universal
> Recommender, which uses the code behind spark-itemsimilarity to serve
> recommendations. Read about the UR here: http://actionml.com/docs/ur <
> http://actionml.com/docs/ur>
>
> On Nov 30, 2016, at 6:58 AM, Niklas Ekvall <niklas.ekvall@gmail.com>
> wrote:
>
> I found that you can, so ignore my question!
>
> Best reagrds, Niklas
>
> 2016-11-30 15:42 GMT+01:00 Niklas Ekvall <niklas.ekvall@gmail.com>:
>
> > Hello!
> >
> > I'm using *spark-itemsimilarity *to produce related recommendations and
> > the input data has the form *userID, itemID. *Could I also use the from
> *userID,
> > itemID, value* (value > 0)? Or does *spark-itemsimilarity* only handles
> > binary values?
> >
> > Best regards, Niklas
> >
>
>

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