For example, we can partition on the provider_city and provider_state variables to create a set of partitions, each containing the rows with a given unique combination of provider_city and provider_state. Our partitioned variable average_reimbursement_per_city computes a mean of average_remibursement across all rows in the partition and assigns that value to every row in the partition. So all records fromCHANDLER, AZ are assigned a computed average_reimbursement_per_city value, all records from MESA, AZ are assigned a different computed average_reminbursement_per_city value, and so on.