Can you provide more detail on the 'place' ids
Are they related in any way
Is it just zip codes? Or types of location (home/work/gym/restaurant)
Basically you need to make the similarities explicit
Depending on what exactly these are will depend on how you can make them explicit
Are you trying to predict a pair of unknown place ids or each place I'd is known, but not that particular combination
Can you provide more detail on the 'place' ids
Are they related in any way
Is it just zip codes? Or types of location (home/work/gym/restaurant)
Basically you need to make the similarities explicit
Depending on what exactly these are will depend on how you can make them explicit
Are you trying to predict a pair of unknown place ids or each place I'd is known, but not that particular combination