I have a list of customers. Customers have between 1 - 20 "Jobs" that flow through a front end engineering effort to get details specified. The jobs are all similar but different in their details. We know that each customer has their own kind of profile in terms of how long they take to get answers back and to perform approvals. I have statistics about turn times of jobs for those customers:
Customer Days ________ ____ Cust A, job 1 17 Cust A, Job 2 13 Cust B, Job 1 29 Cust B, Job 2 18 ... Cust Z, Job 999 32
I need to identify what customers (on average) have jobs that take too long. I understand how to determine a correlation when I am comparing two numbers like temperature (degrees F) and speed (MPH). I don't understand how to determine this when one of the variables is text (customer name).
How do I determine the customers who's jobs take longer on average?