Re: Negative preferences

2014-08-15 Thread Sean Owen
I have used thumbs-down-like interactions as like an anti-click, and subtracts from the interaction between the user and item. The negative scores can be naturally applied in a matrix-factorization-like model like ALS, but that's not the situation here. Others probably have better first-hand

Re: Negative preferences

2014-08-15 Thread Pat Ferrel
I like the negative click analogy. The data shows an explicit interaction—using only thumbs up ignores that interaction. Yes, the cooccurrence style recommender can’t account for these in the same way ALS does but filtering them seems like a close approximation and maybe good enough. #1 asks

Re: Negative preferences

2014-08-15 Thread Ted Dunning
It is bad practice to use weightings to express different actions. This may be necessary in an ALS framework, but it is still a bad idea. A much better approach is to use multi-modal recommendation in which each action is used independently in a cross-recommendation fashion to measure predictive

Re: Negative preferences

2014-08-15 Thread Pat Ferrel
On Aug 15, 2014, at 9:05 AM, Ted Dunning ted.dunn...@gmail.com wrote: It is bad practice to use weightings to express different actions. This may be necessary in an ALS framework, but it is still a bad idea. A much better approach is to use multi-modal recommendation in which each

Re: Negative preferences

2014-08-15 Thread Ted Dunning
On Fri, Aug 15, 2014 at 2:24 PM, Pat Ferrel pat.fer...@gmail.com wrote: On Aug 15, 2014, at 9:05 AM, Ted Dunning ted.dunn...@gmail.com wrote: It is bad practice to use weightings to express different actions. This may be necessary in an ALS framework, but it is still a bad idea. A

Negative preferences

2014-08-14 Thread Pat Ferrel
Now that we have multi-action/cross-cooccurrences in ItemSimilarity we can start playing with taking in multiple actions to recommend one. On the demo site I have data for thumbs up and down but have only been using thumbs up as the primary action. I then filter recs by a user’s thumbs down

Re: Negative Preferences in a Recommender

2013-06-18 Thread Sean Owen
Yes the model has no room for literally negative input. I think that conceptually people do want negative input, and in this model, negative numbers really are the natural thing to express that. You could give negative input a small positive weight. Or extend the definition of c so that it is

Re: Negative Preferences in a Recommender

2013-06-18 Thread Ted Dunning
I have found that in practice, don't-like is very close to like. That is, things that somebody doesn't like are very closely related to the things that they do like. Things that are quite distant wind up as don't-care, not don't-like. This makes most simple approaches to modeling polar

Re: Negative Preferences in a Recommender

2013-06-18 Thread Pat Ferrel
To your point Ted, I was surprised to find that remove-from-cart actions predicted sales almost as well as purchases did but it also meant filtering from recs. We got the best scores treating them as purchases and not recommending them again. No one pried enough to get get bothered. In this

Re: Negative Preferences in a Recommender

2013-06-18 Thread Pat Ferrel
They are on a lot of papers, which are you looking at? On Jun 17, 2013, at 6:30 PM, Dmitriy Lyubimov dlie...@gmail.com wrote: (Kinda doing something very close. ) Koren-Volynsky paper on implicit feedback can be generalized to decompose all input into preference (0 or 1) and confidence matrices

Re: Negative Preferences in a Recommender

2013-06-18 Thread Sean Owen
I'm suggesting using numbers like -1 for thumbs-down ratings, and then using these as a positive weight towards 0, just like positive values are used as positive weighting towards 1. Most people don't make many negative ratings. For them, what you do with these doesn't make a lot of difference.

Re: Negative Preferences in a Recommender

2013-06-18 Thread Dmitriy Lyubimov
Koren, Volinsky: CF for implicit feedback datasets On Tue, Jun 18, 2013 at 8:07 AM, Pat Ferrel p...@occamsmachete.com wrote: They are on a lot of papers, which are you looking at? On Jun 17, 2013, at 6:30 PM, Dmitriy Lyubimov dlie...@gmail.com wrote: (Kinda doing something very close. )

Re: Negative Preferences in a Recommender

2013-06-18 Thread Dmitriy Lyubimov
On Tue, Jun 18, 2013 at 3:48 AM, Ted Dunning ted.dunn...@gmail.com wrote: I have found that in practice, don't-like is very close to like. That is, things that somebody doesn't like are very closely related to the things that they do like. I guess it makes sense for cancellations. i guess

Re: Negative Preferences in a Recommender

2013-06-17 Thread Dmitriy Lyubimov
(Kinda doing something very close. ) Koren-Volynsky paper on implicit feedback can be generalized to decompose all input into preference (0 or 1) and confidence matrices (which is essentually an observation weight matrix). If you did not get any observations, you encode it as (p=0,c=1) but if