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From Masha Zaharchenko <mashast...@gmail.com>
Subject Re: UR: getting score for the given item
Date Wed, 01 Mar 2017 20:06:29 GMT
Yes, I want to use these scores to rank search results. And it`s unclear to
me if I can compare scores returned by different queries(especially queries
which use item id to get recommendations of similar items).

E.g. A user *u1* had searched for keyword *"cat"* and two items were
returned. Items ids are* id1* and* id2*.

We make two queries which look like this:

curl -H "Content-Type: application/json" -d '{ "user": "u1
","item":"i1","num":1,"returnSelf":true}'  http://localhost:8000/queries.
json

curl -H "Content-Type: application/json" -d '{ "user": "u1
","item":"i2","num":1,"returnSelf":true}'  http://localhost:8000/queries.
json


And we get two responses:

{"itemScores":[{"item":"i1","score":5}]}
{"itemScores":[{"item":"i2","score":4}]}


The question is: Can we use these scores(4 and 5) to rank the items?

On Wed, Mar 1, 2017 at 7:01 PM, Pat Ferrel <pat@occamsmachete.com> wrote:

> The scores are the sum of dot product between the user’s history vectors
> and the item’s indicator vectors, with norms and boosts applied for score
> calculation. Search this list for more discussion. The math means the more
> indicators or boosts the higher the possible value. These are exactly like
> the scores you get back from Searching with keywords. They have a precise
> mathematical meaning but are only used to rank results. they are returned
> in a form sorted by score.
>
> Are you trying to use the scores?
>
>
> On Feb 28, 2017, at 11:23 PM, Masha Zaharchenko <mashastudy@gmail.com>
> wrote:
>
> Hi, everyone!
>
> I`m currently trying to use the UR to solve the ranking problem by getting
> scores for the each item on the list, but results are quite ambiguous and
> I`m not sure how to interpret them.
> (I`m aware of the existence of Product Ranking Engine Template, but I`m
> curious if  I can do it with the UR)
>
> Suppose I send the following queries:
> A) $ curl -H "Content-Type: application/json" -d '{ "user": "
> 5881C656F1284616BA5D47C42F930497","item":"242234","num":1,"returnSelf":true}'
> http://localhost:8000/queries.json
> Response: {"itemScores":[{"item":"242234","score":50.42802810668945}]}
>
> B)$ curl -H "Content-Type: application/json" -d '{ "user": "
> 5881C656F1284616BA5D47C42F930497","item":"83364","num":1,"
> returnSelf":true}'
> Response: {"itemScores":[{"item":"83364","score":51.85137176513672}]}
>
> Are these scores comparable or they only have a meaning within the limits
> of the query(i.e. recommending the given item as the most similar to
> itself)?
>
> Thanks,
> Maria
>
>

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