must numeric item and user IDs be sequential, for bin/mahout itemsimilarity?

[Dan Brickley <da...@danbri.org>]

I recall having problems with this before, using the non-Mahout Taste
code. I have meaningful strings for content IDs and had mapped them
systematically to pseudo-meaningful (but non-sequential) numbers. I
remember that causing some problems a year or so back, ... but I'm
trying it again now with the itemsimilarity Hadoop job. If I need to
iterate through all rows in the log and generate consecutive counts to
identify items and users I guess I could, though it doesn't seem very
Hadoop-friendly. Or should I be OK with anything that's int-shaped?

Dan

Re: must numeric item and user IDs be sequential, for bin/mahout itemsimilarity?

[Dan Brickley <da...@danbri.org>]

On 6 July 2012 19:36, Sean Owen <sr...@gmail.com> wrote:
> I don't recall that it has ever caused a problem, no. The values are
> just keys in a hashtable, so don't need to be sequential.

Thanks, Sean. Quite possibly I was misinterpreting something; I've not
managed to track down the source of my belief and am happy to abandon
it :)

Dan

Re: must numeric item and user IDs be sequential, for bin/mahout itemsimilarity?

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

I don't recall that it has ever caused a problem, no. The values are
just keys in a hashtable, so don't need to be sequential.

On Fri, Jul 6, 2012 at 8:26 PM, Dan Brickley <da...@danbri.org> wrote:
> I recall having problems with this before, using the non-Mahout Taste
> code. I have meaningful strings for content IDs and had mapped them
> systematically to pseudo-meaningful (but non-sequential) numbers. I
> remember that causing some problems a year or so back, ... but I'm
> trying it again now with the itemsimilarity Hadoop job. If I need to
> iterate through all rows in the log and generate consecutive counts to
> identify items and users I guess I could, though it doesn't seem very
> Hadoop-friendly. Or should I be OK with anything that's int-shaped?
>
> Dan