A computer system and set of routines with access to venue maps, merchandizing plans, and store catalogs for a merchant attempts to assign locations to items in the store catalog based on the merchandizing plan and map; when a location cannot be assigned to an item in a venue, a proxy location is determined based on categories associated with the item, a number of merchandising plans across the venues in which the item occurs, and/or clusters of items. An error is also determined in relation to the assigned location. The assigned location and error are output, for example, to guide people to the items.