(Any similarities to the student shop at the University of Hertfordshire are entirely coincidental. This is a
fictional example.)
The Students’ Union Shop is trying to work out how many cashiers it needs to employ in order to provide an
adequate service level. Customers at the shop line up in a single queue and are called forward to pay for their
purchases when a till becomes free. To help determine the busy times of the day, the shop has recorded the
number of customers arriving at the tills in each 5-minute interval during the shop’s opening hours, from 8am
until 6pm (N.B. this is the number who actually make a purchase and does not include customers who are just
browsing). Records for a period of 5 weeks are available. All the data were collected during term time.
The shop usually functions with just three cashiers but it has the capacity to support up to 6. The shop is open
for approximately 50 weeks each year. The management has also collected data about the time it takes for
cashiers to take payment. These data come from term time and 1000 records are available. Management are
concerned that customers wishing to buy food, in particular, may be going to other outlets within the university
such as the Big Ears Sandwich Shop or the Noddy Bar. Management are also concerned about the turnover of
their staff and would like to reduce their stress and also stop them getting bored. They would be interested to
hear about any innovative operating strategies for doing this.
You are employed as a consultant for the Students’ Union Shop. The shop management would like to hear
insights from you, but does have a few specific questions they would like to ask. These are
What is the average customer arrival rate per hour based on the current data?
The management reckons there are more customers during the lunch break, and would like you to look
into this matter. Could you spot any busier period during the day? If so, what are the busier hours?
o What is the average customer arrival rate per hour during busier period?
o What is the average customer arrival rate per hour during quieter period?
How fast on average does a cashier serve a customer in our shop?
o Have you spotted any outlier in the collected service data? If yes, did you include (or exclude)
those outliers when coming up the average, and why?

How many cashiers does the shop need to have a reasonable performance?
o When taking the average daily arrival? Would you consider the average daily arrival a good
measure for cashier arrangement, and why?
o During busier period if observed?
o During quieter period if observed?

The shop management is also interested in hearing your thoughts on how the adoption of business analytics in
general could positively impact the shop performance. (For students who participant in the Young Enterprise
competition AND wish to work this part in their YE group, please see alternative arrangement here.) They would
appreciate that you keep this part under 2 pages.

What You Should Produce
You are required to produce a model using Excel, which could be used by the Students’ Union Shop
management team for evaluation of their performance using the data provided or any new data that becomes

available in a similar format. If there is any further information you believe to be essential, make a realistic
assumption and explain clearly what you have done (in the report below).
The model should be supported by a comprehensive report in which you should report on their current system,
pointing out any existing problems, and suggest ways of improving the service level. You must give a
convincing argument to support the improvements you are suggesting, e.g. by showing the benefit of adding
an extra cashier in terms of staff utilisation and customer waiting time.
Length of Report
The Students’ Union Shop management team are very busy and so value concise reports. Your report (include
Executive Summary, see below) should be no more than 15 pages.
You are also required to include an Executive Summary at the beginning of your report. It should summarise
your findings on management’s specific questions listed in the Background above. The Executive Summary
should be no more than 2 pages.

Data
The data on customer arrivals and cashiers’ service times are available on the module site under Assignment,
Business Analytics. https://herts.instructure.com/courses/102855/assignments/203508

General Restriction
Visual Basic for Application (VBA) code should NOT be used for solving the problem. If you have never heard
of it, then consider yourself good with this restriction.

Mark scheme:
Note that this assignment is deliberately open-ended and initiative will be rewarded. The assignment will be
marked out of 100.
1. Excel Model
1.1.A suitable queueing model (5%)
1.2.A working model (5%)
1.3.Shop management able to evaluate performance using any new data in a similar format (5%)
1.4.Initiation / creativity, e.g. graphs, presentation (5%)
2. Executive Summary (10%)
3. Report
3.1.What is the average customer arrival rate per hour based on the current data? (5%)
3.2.The management reckons there are more customers during the lunch break, and would like you to look
into this matter. Could you spot any busier period during the day? If so, what are the busier hours? (5%)
3.2.1. What is the average customer arrival rate per hour during busier period? (5%)
3.2.2. What is the average customer arrival rate per hour during quieter period? (5%)
3.3.How fast on average does a cashier serve a customer in our shop? (5%)
3.3.1. Have you spotted any outlier in the collected service data? If yes, did you include (or exclude)

those outliers when coming up the average, and why? (5%)

3.4.How many cashiers does the shop need to have a reasonable performance,
3.4.1. When taking the average daily arrival? Would you consider the average daily arrival a good

measure for cashier arrangement, and why? (5%)

3.4.2. During busier period if observed? (5%)

3.4.3. During quieter period if observed? (5%)
3.5.Thoughts on how the adoption of business analytics in general could positively impact the shop
performance (For students who participant in the Young Enterprise competition AND wish to work this
part in their YE group, please see alternative arrangement here.) (25%)