A system is provided that extrapolates item characteristics from items considered to possess a characteristic to items not known to possess the characteristic. The system may include an item data repository that stores data representing physical items. These items can include first items having a characteristic and second items not known to have the characteristic. A characteristic extrapolation module can extrapolate the characteristic from at least some of the first items to at least some of the second items based at least in part on the strength of associations between the plurality of items. A recommendations module may provide item recommendations based at least partly on the characteristic of the items.