A computer-programming department does code writing and consultation for internal departments. Their services include code writing for new applications (29% of their time), code writing for updates to existing applications (38% of their time), and telephone consultation with clients on the use of current software (33% of their time). Their performance metrics indicate that when processes are stable, an average of 1.32 programming errors are made per 100 lines of new code and 4.7 programming errors are made per 100 lines of updated code. New code is completed on or before the deadline in 84% of projects, and updated code is completed on or before the deadline 91% of projects. New code clients average of 4.8 follow up questions per project completed within 30 days and update projects average 2.2 follow up questions per project completed within 30 days. Each quarter, a random selection of callers is asked to complete a satisfaction survey until 40 agree (this adds some time to each call). In these surveys, 79% of callers seeking consultation are satisfied with the accuracy of the advice received. At times, clients need to call more than once to get their problem solved. Records show that an average of 1.4 "recalls" are made within 5 days of the original call. The percentage of callers on hold for more than 5 minutes is 12%. The likelihood that a caller agrees to take the satisfaction survey is 54.1%. During the last quarter, the following performance data were collected. For each row in the table, consider the use of a probability model to determine if the data indicate that the process has become unstable (and if so, whether it gotten better or worse) or if the process is stable and the outcome data vary randomly. Metric Information Programming Errors: New Code Programming Errors: Updated Code Completed Late: New Code Completed Late: Updated Code Follow-Up Questions: New Code Follow-Up Questions: Update Code Consultation Satisfaction Consultation Recalls On Hold More Than 5 Minutes Callers Asked to Complete Survey Sample Size Information 37809 lines of code generated, 2367 lines inspected 14659 lines of code generated, 1008 lines inspected 19 Projects 65 Projects 32 Projects (Within 30 Days) 71 Projects (Within 30 Days) 174 Calls, 40 Complete Survey 167 Calls (Within 5 Days) 174 Calls N/A Outcome Information 14 Programming Errors 35 Programming Errors 4 Completed Late 3 Completed Late 162 Follow-Up Questions 198 Follow-Up Questions 73% were Satisfied 274 Recalls 16% on hold >5 Minutes 79 Callers Asked Binomial Model Analysis Inputs: Sample Size (n) Outcome Proportion Probability Probability of Success (p) Poisson Model Analysis Inputs: Sample Size (n) Outcome Proportion Probability Average Unit Count (u)