An RFID-based inventory management system comprising: a plurality of RFID-readable product tags each associated with a piece of merchandise and programmed to generate a signal containing information regarding the associated piece of merchandise; an RFID reader capable of sending signals to and receiving signals from said product tags; and a processor capable of receiving signals from the RFID reader with information regarding said product tags and programmed to: compare the information regarding two or more of said product tags, determine whether said two or more product tags are part of a moving group being moved together by monitoring any change in the individual signals over time and then compare the movement of one product tag to another product tag to determine whether they are sufficiently similar that the probability of them being moved together exceeds a threshold value, and generate an output based at least in part on the signals being sent from the product tags in the moving group, characterized in that the signals generated by the product tags include information related to the weight of the associated piece of merchandise, and in that the output generated by the processor is an alert to provide assistance in the vicinity of the moving group of product tags based at least in part on the combined weight of the pieces of merchandise in the moving group. a plurality of RFID-readable product tags each associated with a piece of merchandise and programmed to generate a signal containing information regarding the associated piece of merchandise; an RFID reader capable of sending signals to and receiving signals from said product tags; and a processor capable of receiving signals from the RFID reader with information regarding said product tags and programmed to: compare the information regarding two or more of said product tags, determine whether said two or more product tags are part of a moving group being moved together by monitoring any change in the individual signals over time and then compare the movement of one product tag to another product tag to determine whether they are sufficiently similar that the probability of them being moved together exceeds a threshold value, and generate an output based at least in part on the signals being sent from the product tags in the moving group, characterized in that the signals generated by the product tags include information related to the weight of the associated piece of merchandise, and in that the output generated by the processor is an alert to provide assistance in the vicinity of the moving group of product tags based at least in part on the combined weight of the pieces of merchandise in the moving group. compare the information regarding two or more of said product tags, determine whether said two or more product tags are part of a moving group being moved together by monitoring any change in the individual signals over time and then compare the movement of one product tag to another product tag to determine whether they are sufficiently similar that the probability of them being moved together exceeds a threshold value, and generate an output based at least in part on the signals being sent from the product tags in the moving group, characterized in that the signals generated by the product tags include information related to the weight of the associated piece of merchandise, and in that the output generated by the processor is an alert to provide assistance in the vicinity of the moving group of product tags based at least in part on the combined weight of the pieces of merchandise in the moving group.