spark-itemsimilarity question: what's the difference between indicator-matrix and cross-indicator-matrix

[Kevin Zhang <zh...@yahoo.com.INVALID>]

May I say indicator-matrix is for the main action for example purchase and the cross-indicator-matrix is for the secondary action?

Thanks a lot,
Kevin

Re: spark-itemsimilarity question: what's the difference between indicator-matrix and cross-indicator-matrix

[Pat Ferrel <pa...@occamsmachete.com>]

Yes, you have it right. The user’s history of the primary acton (purchase) is used as a query against the indicator-matrix and the user’s history of the secondary action (detail-view for instance) is used against the “cross-indicator”

But the terminology is being changed to reflect what Ted is saying.
1) The new (current master) naming of the outputs are “similarity-matrix” and “cross-similarity-matrix”, which are LLR measured cooccurrence and cross-cooccurrence. A cross-indicator is not a thing really and is a confusing name.
2) The secondary actions may be many. The CLI job only supports 1 primary and 1 secondary but you can run it in pairs with 1 primary and many secondaries. Also the internal code can calculate correlation between the action you want to recommend and many other actions. All of which create indicators which you query with different history.

On Mar 6, 2015, at 3:08 PM, Ted Dunning <te...@gmail.com> wrote:


The terms main and secondary are a bit confusing. 

The easiest definition is that cooccurrence analyzes the record of actions you want to recommend. Cross occurrence tries to transfer from one behavior to another. 

In practice, it has been common to conflate many behaviors into one precisely because cross occurrence analysis was not feasible. Now that it is available standard practice is moving toward retaining distinction where possible.  

Sent from my iPhone

> On Mar 6, 2015, at 11:08, Kevin Zhang <zh...@yahoo.com.INVALID> wrote:
> 
> May I say indicator-matrix is for the main action for example purchase and the cross-indicator-matrix is for the secondary action?
> 
> Thanks a lot,
> Kevin

Re: spark-itemsimilarity question: what's the difference between indicator-matrix and cross-indicator-matrix

[Ted Dunning <te...@gmail.com>]

The terms main and secondary are a bit confusing. 

The easiest definition is that cooccurrence analyzes the record of actions you want to recommend. Cross occurrence tries to transfer from one behavior to another. 

In practice, it has been common to conflate many behaviors into one precisely because cross occurrence analysis was not feasible. Now that it is available standard practice is moving toward retaining distinction where possible.  

Sent from my iPhone

> On Mar 6, 2015, at 11:08, Kevin Zhang <zh...@yahoo.com.INVALID> wrote:
> 
> May I say indicator-matrix is for the main action for example purchase and the cross-indicator-matrix is for the secondary action?
> 
> Thanks a lot,
> Kevin