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From Thomas Rewig <tre...@mufin.com>
Subject Re: Memory and Speed Questions for Item-Based-Recommender
Date Tue, 14 Jul 2009 10:12:17 GMT
Sean Owen schrieb:
> On Tue, Jul 14, 2009 at 10:58 AM, Thomas Rewig<trewig@mufin.com> wrote:
>   
>> Because I need a UserSimilarity to precompute. Maybe I overlook a importent
>> detail, but if I do it in that way to compute all on the fly in a item-based
>> way:
>>
>>       *** "Pre"-Recommender ***
>>       // set the model for the ItemItemMatrix
>>      this.similarityModel = new MySQLJDBCDataModel(cPoolDS,
>> preferenceTableSim, userIDColumnSim, itemIDColumnSim, preferenceColumnSim);
>>       // set the "ItemSimilarity" for the ItemItemMatrix
>>      this.similarityItemSimilarity = new
>> EuclideanDistanceSimilarity(this.similarityModel);
>>       // set CaschingSimilarity
>>      this.cachingItemSimilarity = new
>> CachingItemSimilarity(this.similarityItemSimilarity, this.similarityModel);
>>       *** Recommender ***
>>      // set the model for the Recommender
>>      this.model = new MySQLJDBCDataModel(cPoolDS, preferenceTable,
>> userIDColumn, itemIDColumn, preferenceColumn);
>>      // set the Recommender with the *cachingItemSimilarity*
>>      this.recommender = new GenericUserBasedRecommender(this.model,
>> this.cachingItemSimilarity);
>>     
>
> But why are you using a user-based recommender here? I thought you
> were using an item-based recommender, in the end, to produce actual
> recommendations. Yes, of course you do not plug in an item-similarity
> metric into a user-based recommender.
>
> User GenericItemBasedRecommender.
>   
Oh I think I need a coffee ... in my code it is a 
GenericItemBasedRecommender, I have to improve my copy&paste ...

this.recommender = new GenericItemBasedRecommender(this.model,this.cachingItemSimilarity);


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