Yup, that is true and a reasonable clarification of the doc.
On Thu, 23 Mar 2017 at 00:03 chris snow <chsnow...@gmail.com> wrote:
> The documentation for collaborative filtering is as follows:
>
> ===
> Scaling of the regularization parameter
>
> Since v1.1, we scale the regularization parameter lambda in solving
> each least squares problem by the number of ratings the user generated
> in updating user factors, or the number of ratings the product
> received in updating product factors.
> ===
>
> I find this description confusing, probably because I lack a detailed
> understanding of ALS. The wording suggest that the number of ratings
> change ("generated", "received") during solving the least squares.
>
> This is how I think I should be interpreting the description:
>
> ===
> Since v1.1, we scale the regularization parameter lambda when solving
> each least squares problem. When updating the user factors, we scale
> the regularization parameter by the total number of ratings from the
> user. Similarly, when updating the product factors, we scale the
> regularization parameter by the total number of ratings for the
> product.
> ===
>
> Have I understood this correctly?
>
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