Candice Worthy and Philip Hanson are day shift supervisors
at National Call Center’s Austin, Texas, facility. National provides contract
call center services for a number of companies, including banks and major
retail companies. Candice and Philip have both been with the company for
slightly more than five years, having joined National right after graduating
with bachelor’s degrees from the University of Texas. As they walked down the
hall together after the weekly staff meeting, the two friends were discussing
the assignment they were just handed by Mark Gonzales, the division manager.
The assignment came out of a discussion at the meeting in which one of
National’s clients wanted a report describing the calls being handled for them
by National. Mark had asked Candice and Philip to describe the data in a file
called National Call Center and produce a report that would both graphically
and numerically analyze the data. The data are for a sample of 57 calls and for
the following variables:
Account Number
Caller Gender
 Account Holder Gender
Past Due Amount
 Current Account Balance
Nature of Call (Billing Question or Other)
 By the time they reached their office, Candice and Philip
had outlined some of the key tasks that they needed to do.
Required Tasks:
1. Develop bar charts showing the mean and median current
account balance by gender of the caller.
2. Develop bar charts showing the mean and median current
account balance by gender of the account holder.
 3. Construct a scatter diagram showing current balance on
the horizontal axis and past due amount on the vertical axis.
4. Compute the key descriptive statistics for the center and
for the variation in current account balance broken down by gender of the
caller, gender of the account holder, and by the nature of the call.
5. Repeat task 4 but compute the statistics for the past due
balances.
 6. Compute the coefficient of variation for current account
balances for male and female account holders.
7. Develop frequency and relative frequency distributions
for the gender of callers, gender of account holders, and nature of the calls.
 8. Develop joint frequency and joint relative frequency
distributions for the account holder gender by whether or not the account has a
past due balance.
9. Write a report to National’s client that contains the
results for tasks 1–8 along with a discussion of these statistics and graphs.