Question - Mahout Taste - User-Based Recommendations...

[Henning Kuich <hk...@gmail.com>]

Dear All,

I am wondering if I understand the User-based recommendation algorithm
correctly.

I need to be able to answer the following questions, given users and
ratings:

1) Which users are "closest" to a given user
and
2) given a user and a product, predict the preference for the product

apart from the standard "return topN" recommendations. But as I understand
it, the above two questions are just "subquestions" of the topN problem,
correct? Because the algorithm determines the "closest users" since it's a
user-based recommender, and since it calculates all potential user-item
associations, the second question should also be taken care of.

Do I understand this correctly?

I would greatly appreciate any help,

Henning




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Re: Question - Mahout Taste - User-Based Recommendations...

[Henning Kuich <hk...@gmail.com>]

thanks a lot!


On Tue, Jan 29, 2013 at 3:45 PM, Xavier Rampino
<xr...@senscritique.com>wrote:

> Just to add that you can also
> use UserNeighborhood.getUserNeighborhood(userId) to find the most similar
> users to a given one, should you want to.
>
> On Tue, Jan 22, 2013 at 9:02 PM, Henning Kuich <hk...@gmail.com> wrote:
>
> > ok, thanks!
> >
> >
> > On Tue, Jan 22, 2013 at 8:59 PM, Sean Owen <sr...@gmail.com> wrote:
> >
> > > That's a question of using item-item similarity. For that you need to
> > > use something based on an ItemSimilarity, which is not user-based but
> > > instead the item-based implementation. Or you can just use
> > > ItemSimilarity directly to iterate over the possibilities and find
> > > most similar, but, the recommender would do it for you.
> > >
> > > On Tue, Jan 22, 2013 at 7:50 PM, Henning Kuich <hk...@gmail.com>
> wrote:
> > > > Oh, I forgot one thing: Is it just as simple using the User-based
> > > > recommendation to find similar products, or is this only possible
> using
> > > > item-based recommendations? So basically if a given user rated a
> > certain
> > > > product with x stars, to figure out what item is most like the one he
> > has
> > > > just rated, but using only user-based recommendation algorithms?
> > > >
> > > > HK
> > > >
> > > >
> > > > On Tue, Jan 22, 2013 at 7:44 PM, Henning Kuich <hk...@gmail.com>
> > wrote:
> > > >
> > > >> That's what i though. I just wanted to make sure!
> > > >>
> > > >> Thanks so much for the quick reply!
> > > >>
> > > >> HK
> > > >>
> > > >>
> > > >>
> > > >> On Tue, Jan 22, 2013 at 7:40 PM, Sean Owen <sr...@gmail.com>
> wrote:
> > > >>
> > > >>> Yes that's right. Look as
> UserBasedRecommender.mostSimilarUserIDs(),
> > > >>> and Recommender.estimatePreference(). These do what you are
> > interested
> > > >>> in, and yes they are easy since they are just steps in the
> > > >>> recommendation process anyway.
> > > >>>
> > > >>> On Tue, Jan 22, 2013 at 6:38 PM, Henning Kuich <hk...@gmail.com>
> > > wrote:
> > > >>> > Dear All,
> > > >>> >
> > > >>> > I am wondering if I understand the User-based recommendation
> > > algorithm
> > > >>> > correctly.
> > > >>> >
> > > >>> > I need to be able to answer the following questions, given users
> > and
> > > >>> > ratings:
> > > >>> >
> > > >>> > 1) Which users are "closest" to a given user
> > > >>> > and
> > > >>> > 2) given a user and a product, predict the preference for the
> > product
> > > >>> >
> > > >>> > apart from the standard "return topN" recommendations. But as I
> > > >>> understand
> > > >>> > it, the above two questions are just "subquestions" of the topN
> > > problem,
> > > >>> > correct? Because the algorithm determines the "closest users"
> since
> > > >>> it's a
> > > >>> > user-based recommender, and since it calculates all potential
> > > user-item
> > > >>> > associations, the second question should also be taken care of.
> > > >>> >
> > > >>> > Do I understand this correctly?
> > > >>> >
> > > >>> > I would greatly appreciate any help,
> > > >>> >
> > > >>> > Henning
> > > >>> >
> > > >>> >
> > > >>> >
> > > >>> >
> > > >>> > Confidentiality Notice: This e-mail message, including any
> > > >>> > attachments, is for the sole use of the intended recipient(s) and
> > may
> > > >>> > contain confidential and privileged information.  Any
> unauthorized
> > > >>> > review, use, disclosure or distribution is prohibited.  If you
> are
> > > not
> > > >>> > the intended recipient, please contact the sender by reply e-mail
> > and
> > > >>> > destroy all copies of the original message.
> > > >>>
> > > >>
> > > >>
> > > >>
> > > >> Confidentiality Notice: This e-mail message, including any
> > > >> attachments, is for the sole use of the intended recipient(s) and
> may
> > > >> contain confidential and privileged information.  Any unauthorized
> > > >> review, use, disclosure or distribution is prohibited.  If you are
> not
> > > >> the intended recipient, please contact the sender by reply e-mail
> and
> > > >> destroy all copies of the original message.
> > > >>
> > > >
> > > > Confidentiality Notice: This e-mail message, including any
> > > > attachments, is for the sole use of the intended recipient(s) and may
> > > > contain confidential and privileged information.  Any unauthorized
> > > > review, use, disclosure or distribution is prohibited.  If you are
> not
> > > > the intended recipient, please contact the sender by reply e-mail and
> > > > destroy all copies of the original message.
> > >
> >
> >
>
>

Re: Question - Mahout Taste - User-Based Recommendations...

[Xavier Rampino <xr...@senscritique.com>]

Just to add that you can also
use UserNeighborhood.getUserNeighborhood(userId) to find the most similar
users to a given one, should you want to.

On Tue, Jan 22, 2013 at 9:02 PM, Henning Kuich <hk...@gmail.com> wrote:

> ok, thanks!
>
>
> On Tue, Jan 22, 2013 at 8:59 PM, Sean Owen <sr...@gmail.com> wrote:
>
> > That's a question of using item-item similarity. For that you need to
> > use something based on an ItemSimilarity, which is not user-based but
> > instead the item-based implementation. Or you can just use
> > ItemSimilarity directly to iterate over the possibilities and find
> > most similar, but, the recommender would do it for you.
> >
> > On Tue, Jan 22, 2013 at 7:50 PM, Henning Kuich <hk...@gmail.com> wrote:
> > > Oh, I forgot one thing: Is it just as simple using the User-based
> > > recommendation to find similar products, or is this only possible using
> > > item-based recommendations? So basically if a given user rated a
> certain
> > > product with x stars, to figure out what item is most like the one he
> has
> > > just rated, but using only user-based recommendation algorithms?
> > >
> > > HK
> > >
> > >
> > > On Tue, Jan 22, 2013 at 7:44 PM, Henning Kuich <hk...@gmail.com>
> wrote:
> > >
> > >> That's what i though. I just wanted to make sure!
> > >>
> > >> Thanks so much for the quick reply!
> > >>
> > >> HK
> > >>
> > >>
> > >>
> > >> On Tue, Jan 22, 2013 at 7:40 PM, Sean Owen <sr...@gmail.com> wrote:
> > >>
> > >>> Yes that's right. Look as UserBasedRecommender.mostSimilarUserIDs(),
> > >>> and Recommender.estimatePreference(). These do what you are
> interested
> > >>> in, and yes they are easy since they are just steps in the
> > >>> recommendation process anyway.
> > >>>
> > >>> On Tue, Jan 22, 2013 at 6:38 PM, Henning Kuich <hk...@gmail.com>
> > wrote:
> > >>> > Dear All,
> > >>> >
> > >>> > I am wondering if I understand the User-based recommendation
> > algorithm
> > >>> > correctly.
> > >>> >
> > >>> > I need to be able to answer the following questions, given users
> and
> > >>> > ratings:
> > >>> >
> > >>> > 1) Which users are "closest" to a given user
> > >>> > and
> > >>> > 2) given a user and a product, predict the preference for the
> product
> > >>> >
> > >>> > apart from the standard "return topN" recommendations. But as I
> > >>> understand
> > >>> > it, the above two questions are just "subquestions" of the topN
> > problem,
> > >>> > correct? Because the algorithm determines the "closest users" since
> > >>> it's a
> > >>> > user-based recommender, and since it calculates all potential
> > user-item
> > >>> > associations, the second question should also be taken care of.
> > >>> >
> > >>> > Do I understand this correctly?
> > >>> >
> > >>> > I would greatly appreciate any help,
> > >>> >
> > >>> > Henning
> > >>> >
> > >>> >
> > >>> >
> > >>> >
> > >>> > Confidentiality Notice: This e-mail message, including any
> > >>> > attachments, is for the sole use of the intended recipient(s) and
> may
> > >>> > contain confidential and privileged information.  Any unauthorized
> > >>> > review, use, disclosure or distribution is prohibited.  If you are
> > not
> > >>> > the intended recipient, please contact the sender by reply e-mail
> and
> > >>> > destroy all copies of the original message.
> > >>>
> > >>
> > >>
> > >>
> > >> Confidentiality Notice: This e-mail message, including any
> > >> attachments, is for the sole use of the intended recipient(s) and may
> > >> contain confidential and privileged information.  Any unauthorized
> > >> review, use, disclosure or distribution is prohibited.  If you are not
> > >> the intended recipient, please contact the sender by reply e-mail and
> > >> destroy all copies of the original message.
> > >>
> > >
> > > Confidentiality Notice: This e-mail message, including any
> > > attachments, is for the sole use of the intended recipient(s) and may
> > > contain confidential and privileged information.  Any unauthorized
> > > review, use, disclosure or distribution is prohibited.  If you are not
> > > the intended recipient, please contact the sender by reply e-mail and
> > > destroy all copies of the original message.
> >
>
>
>
> --
>
> P. Henning J. L. Kuich
> email: hkuich@gmail.com
> twitter: @hkuich <http://twitter.com/hkuich>
> facebook: henning.kuich
> G+: hkuich
> Tel: +49 178 6065116
>
> Confidentiality Notice: This e-mail message, including any
> attachments, is for the sole use of the intended recipient(s) and may
> contain confidential and privileged information.  Any unauthorized
> review, use, disclosure or distribution is prohibited.  If you are not
> the intended recipient, please contact the sender by reply e-mail and
> destroy all copies of the original message.
>

Re: Question - Mahout Taste - User-Based Recommendations...

[Henning Kuich <hk...@gmail.com>]

ok, thanks!


On Tue, Jan 22, 2013 at 8:59 PM, Sean Owen <sr...@gmail.com> wrote:

> That's a question of using item-item similarity. For that you need to
> use something based on an ItemSimilarity, which is not user-based but
> instead the item-based implementation. Or you can just use
> ItemSimilarity directly to iterate over the possibilities and find
> most similar, but, the recommender would do it for you.
>
> On Tue, Jan 22, 2013 at 7:50 PM, Henning Kuich <hk...@gmail.com> wrote:
> > Oh, I forgot one thing: Is it just as simple using the User-based
> > recommendation to find similar products, or is this only possible using
> > item-based recommendations? So basically if a given user rated a certain
> > product with x stars, to figure out what item is most like the one he has
> > just rated, but using only user-based recommendation algorithms?
> >
> > HK
> >
> >
> > On Tue, Jan 22, 2013 at 7:44 PM, Henning Kuich <hk...@gmail.com> wrote:
> >
> >> That's what i though. I just wanted to make sure!
> >>
> >> Thanks so much for the quick reply!
> >>
> >> HK
> >>
> >>
> >>
> >> On Tue, Jan 22, 2013 at 7:40 PM, Sean Owen <sr...@gmail.com> wrote:
> >>
> >>> Yes that's right. Look as UserBasedRecommender.mostSimilarUserIDs(),
> >>> and Recommender.estimatePreference(). These do what you are interested
> >>> in, and yes they are easy since they are just steps in the
> >>> recommendation process anyway.
> >>>
> >>> On Tue, Jan 22, 2013 at 6:38 PM, Henning Kuich <hk...@gmail.com>
> wrote:
> >>> > Dear All,
> >>> >
> >>> > I am wondering if I understand the User-based recommendation
> algorithm
> >>> > correctly.
> >>> >
> >>> > I need to be able to answer the following questions, given users and
> >>> > ratings:
> >>> >
> >>> > 1) Which users are "closest" to a given user
> >>> > and
> >>> > 2) given a user and a product, predict the preference for the product
> >>> >
> >>> > apart from the standard "return topN" recommendations. But as I
> >>> understand
> >>> > it, the above two questions are just "subquestions" of the topN
> problem,
> >>> > correct? Because the algorithm determines the "closest users" since
> >>> it's a
> >>> > user-based recommender, and since it calculates all potential
> user-item
> >>> > associations, the second question should also be taken care of.
> >>> >
> >>> > Do I understand this correctly?
> >>> >
> >>> > I would greatly appreciate any help,
> >>> >
> >>> > Henning
> >>> >
> >>> >
> >>> >
> >>> >
> >>> > Confidentiality Notice: This e-mail message, including any
> >>> > attachments, is for the sole use of the intended recipient(s) and may
> >>> > contain confidential and privileged information.  Any unauthorized
> >>> > review, use, disclosure or distribution is prohibited.  If you are
> not
> >>> > the intended recipient, please contact the sender by reply e-mail and
> >>> > destroy all copies of the original message.
> >>>
> >>
> >>
> >>
> >> Confidentiality Notice: This e-mail message, including any
> >> attachments, is for the sole use of the intended recipient(s) and may
> >> contain confidential and privileged information.  Any unauthorized
> >> review, use, disclosure or distribution is prohibited.  If you are not
> >> the intended recipient, please contact the sender by reply e-mail and
> >> destroy all copies of the original message.
> >>
> >
> > Confidentiality Notice: This e-mail message, including any
> > attachments, is for the sole use of the intended recipient(s) and may
> > contain confidential and privileged information.  Any unauthorized
> > review, use, disclosure or distribution is prohibited.  If you are not
> > the intended recipient, please contact the sender by reply e-mail and
> > destroy all copies of the original message.
>



-- 

P. Henning J. L. Kuich
email: hkuich@gmail.com
twitter: @hkuich <http://twitter.com/hkuich>
facebook: henning.kuich
G+: hkuich
Tel: +49 178 6065116

Confidentiality Notice: This e-mail message, including any
attachments, is for the sole use of the intended recipient(s) and may
contain confidential and privileged information.  Any unauthorized
review, use, disclosure or distribution is prohibited.  If you are not
the intended recipient, please contact the sender by reply e-mail and
destroy all copies of the original message.

Re: Question - Mahout Taste - User-Based Recommendations...

[Sean Owen <sr...@gmail.com>]

That's a question of using item-item similarity. For that you need to
use something based on an ItemSimilarity, which is not user-based but
instead the item-based implementation. Or you can just use
ItemSimilarity directly to iterate over the possibilities and find
most similar, but, the recommender would do it for you.

On Tue, Jan 22, 2013 at 7:50 PM, Henning Kuich <hk...@gmail.com> wrote:
> Oh, I forgot one thing: Is it just as simple using the User-based
> recommendation to find similar products, or is this only possible using
> item-based recommendations? So basically if a given user rated a certain
> product with x stars, to figure out what item is most like the one he has
> just rated, but using only user-based recommendation algorithms?
>
> HK
>
>
> On Tue, Jan 22, 2013 at 7:44 PM, Henning Kuich <hk...@gmail.com> wrote:
>
>> That's what i though. I just wanted to make sure!
>>
>> Thanks so much for the quick reply!
>>
>> HK
>>
>>
>>
>> On Tue, Jan 22, 2013 at 7:40 PM, Sean Owen <sr...@gmail.com> wrote:
>>
>>> Yes that's right. Look as UserBasedRecommender.mostSimilarUserIDs(),
>>> and Recommender.estimatePreference(). These do what you are interested
>>> in, and yes they are easy since they are just steps in the
>>> recommendation process anyway.
>>>
>>> On Tue, Jan 22, 2013 at 6:38 PM, Henning Kuich <hk...@gmail.com> wrote:
>>> > Dear All,
>>> >
>>> > I am wondering if I understand the User-based recommendation algorithm
>>> > correctly.
>>> >
>>> > I need to be able to answer the following questions, given users and
>>> > ratings:
>>> >
>>> > 1) Which users are "closest" to a given user
>>> > and
>>> > 2) given a user and a product, predict the preference for the product
>>> >
>>> > apart from the standard "return topN" recommendations. But as I
>>> understand
>>> > it, the above two questions are just "subquestions" of the topN problem,
>>> > correct? Because the algorithm determines the "closest users" since
>>> it's a
>>> > user-based recommender, and since it calculates all potential user-item
>>> > associations, the second question should also be taken care of.
>>> >
>>> > Do I understand this correctly?
>>> >
>>> > I would greatly appreciate any help,
>>> >
>>> > Henning
>>> >
>>> >
>>> >
>>> >
>>> > Confidentiality Notice: This e-mail message, including any
>>> > attachments, is for the sole use of the intended recipient(s) and may
>>> > contain confidential and privileged information.  Any unauthorized
>>> > review, use, disclosure or distribution is prohibited.  If you are not
>>> > the intended recipient, please contact the sender by reply e-mail and
>>> > destroy all copies of the original message.
>>>
>>
>>
>>
>> Confidentiality Notice: This e-mail message, including any
>> attachments, is for the sole use of the intended recipient(s) and may
>> contain confidential and privileged information.  Any unauthorized
>> review, use, disclosure or distribution is prohibited.  If you are not
>> the intended recipient, please contact the sender by reply e-mail and
>> destroy all copies of the original message.
>>
>
> Confidentiality Notice: This e-mail message, including any
> attachments, is for the sole use of the intended recipient(s) and may
> contain confidential and privileged information.  Any unauthorized
> review, use, disclosure or distribution is prohibited.  If you are not
> the intended recipient, please contact the sender by reply e-mail and
> destroy all copies of the original message.

Re: Question - Mahout Taste - User-Based Recommendations...

[Henning Kuich <hk...@gmail.com>]

Oh, I forgot one thing: Is it just as simple using the User-based
recommendation to find similar products, or is this only possible using
item-based recommendations? So basically if a given user rated a certain
product with x stars, to figure out what item is most like the one he has
just rated, but using only user-based recommendation algorithms?

HK


On Tue, Jan 22, 2013 at 7:44 PM, Henning Kuich <hk...@gmail.com> wrote:

> That's what i though. I just wanted to make sure!
>
> Thanks so much for the quick reply!
>
> HK
>
>
>
> On Tue, Jan 22, 2013 at 7:40 PM, Sean Owen <sr...@gmail.com> wrote:
>
>> Yes that's right. Look as UserBasedRecommender.mostSimilarUserIDs(),
>> and Recommender.estimatePreference(). These do what you are interested
>> in, and yes they are easy since they are just steps in the
>> recommendation process anyway.
>>
>> On Tue, Jan 22, 2013 at 6:38 PM, Henning Kuich <hk...@gmail.com> wrote:
>> > Dear All,
>> >
>> > I am wondering if I understand the User-based recommendation algorithm
>> > correctly.
>> >
>> > I need to be able to answer the following questions, given users and
>> > ratings:
>> >
>> > 1) Which users are "closest" to a given user
>> > and
>> > 2) given a user and a product, predict the preference for the product
>> >
>> > apart from the standard "return topN" recommendations. But as I
>> understand
>> > it, the above two questions are just "subquestions" of the topN problem,
>> > correct? Because the algorithm determines the "closest users" since
>> it's a
>> > user-based recommender, and since it calculates all potential user-item
>> > associations, the second question should also be taken care of.
>> >
>> > Do I understand this correctly?
>> >
>> > I would greatly appreciate any help,
>> >
>> > Henning
>> >
>> >
>> >
>> >
>> > Confidentiality Notice: This e-mail message, including any
>> > attachments, is for the sole use of the intended recipient(s) and may
>> > contain confidential and privileged information.  Any unauthorized
>> > review, use, disclosure or distribution is prohibited.  If you are not
>> > the intended recipient, please contact the sender by reply e-mail and
>> > destroy all copies of the original message.
>>
>
>
>
> Confidentiality Notice: This e-mail message, including any
> attachments, is for the sole use of the intended recipient(s) and may
> contain confidential and privileged information.  Any unauthorized
> review, use, disclosure or distribution is prohibited.  If you are not
> the intended recipient, please contact the sender by reply e-mail and
> destroy all copies of the original message.
>

Confidentiality Notice: This e-mail message, including any
attachments, is for the sole use of the intended recipient(s) and may
contain confidential and privileged information.  Any unauthorized
review, use, disclosure or distribution is prohibited.  If you are not
the intended recipient, please contact the sender by reply e-mail and
destroy all copies of the original message.

Re: Question - Mahout Taste - User-Based Recommendations...

[Henning Kuich <hk...@gmail.com>]

That's what i though. I just wanted to make sure!

Thanks so much for the quick reply!

HK


On Tue, Jan 22, 2013 at 7:40 PM, Sean Owen <sr...@gmail.com> wrote:

> Yes that's right. Look as UserBasedRecommender.mostSimilarUserIDs(),
> and Recommender.estimatePreference(). These do what you are interested
> in, and yes they are easy since they are just steps in the
> recommendation process anyway.
>
> On Tue, Jan 22, 2013 at 6:38 PM, Henning Kuich <hk...@gmail.com> wrote:
> > Dear All,
> >
> > I am wondering if I understand the User-based recommendation algorithm
> > correctly.
> >
> > I need to be able to answer the following questions, given users and
> > ratings:
> >
> > 1) Which users are "closest" to a given user
> > and
> > 2) given a user and a product, predict the preference for the product
> >
> > apart from the standard "return topN" recommendations. But as I
> understand
> > it, the above two questions are just "subquestions" of the topN problem,
> > correct? Because the algorithm determines the "closest users" since it's
> a
> > user-based recommender, and since it calculates all potential user-item
> > associations, the second question should also be taken care of.
> >
> > Do I understand this correctly?
> >
> > I would greatly appreciate any help,
> >
> > Henning
> >
> >
> >
> >
> > Confidentiality Notice: This e-mail message, including any
> > attachments, is for the sole use of the intended recipient(s) and may
> > contain confidential and privileged information.  Any unauthorized
> > review, use, disclosure or distribution is prohibited.  If you are not
> > the intended recipient, please contact the sender by reply e-mail and
> > destroy all copies of the original message.
>



Confidentiality Notice: This e-mail message, including any
attachments, is for the sole use of the intended recipient(s) and may
contain confidential and privileged information.  Any unauthorized
review, use, disclosure or distribution is prohibited.  If you are not
the intended recipient, please contact the sender by reply e-mail and
destroy all copies of the original message.

Re: Question - Mahout Taste - User-Based Recommendations...

[Sean Owen <sr...@gmail.com>]

Yes that's right. Look as UserBasedRecommender.mostSimilarUserIDs(),
and Recommender.estimatePreference(). These do what you are interested
in, and yes they are easy since they are just steps in the
recommendation process anyway.

On Tue, Jan 22, 2013 at 6:38 PM, Henning Kuich <hk...@gmail.com> wrote:
> Dear All,
>
> I am wondering if I understand the User-based recommendation algorithm
> correctly.
>
> I need to be able to answer the following questions, given users and
> ratings:
>
> 1) Which users are "closest" to a given user
> and
> 2) given a user and a product, predict the preference for the product
>
> apart from the standard "return topN" recommendations. But as I understand
> it, the above two questions are just "subquestions" of the topN problem,
> correct? Because the algorithm determines the "closest users" since it's a
> user-based recommender, and since it calculates all potential user-item
> associations, the second question should also be taken care of.
>
> Do I understand this correctly?
>
> I would greatly appreciate any help,
>
> Henning
>
>
>
>
> Confidentiality Notice: This e-mail message, including any
> attachments, is for the sole use of the intended recipient(s) and may
> contain confidential and privileged information.  Any unauthorized
> review, use, disclosure or distribution is prohibited.  If you are not
> the intended recipient, please contact the sender by reply e-mail and
> destroy all copies of the original message.