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Exercise Solutions (Restricted)

Chapters 1 2 3 4 5 6 7 8 9 11 12

Chapter 3

Question 3.2
What packages would you use in order to organize the development of a system for a video and DVD rental store? What influenced you in your choice of packages?

Here, I was influence by re-use. I pictured hawking my software around all the different shops and enterprises in the locality. I would want the maximum likelihood that units of development could be units of sale. I also thought about the overall mission statement and how it would it have some glaring "and"s. And, of course, terminology would also have given clues -- accounting has different terminology to entertainment.

  • Resource management (DVD, video, game, ...)
  • Customer management (personal details, membership and subscription, ...)
  • Merchandising (soda, Pringles®, blank DVD-Rs (or perhaps that wouldn't be such a good idea), ..., i.e. stock system)
  • Money handling (i.e. accounting)

Question 3.3
Consider POLLY, the computer system to help the owners of small to medium sized hotels with their administration. Write the mission statement (or statement of purpose) for such a system. It might help to imagine you are marketing or selling the system. Assess the focus or cohesion (and completeness and honesty) of your mission statement. If you feel that it is incohesive or diffuse, propose some packaging for the system and write a mission statement for each package, again assessing the focus and cohesion.

A first mission statement might go like this:

"A system to accurately and optimally book and bill guests and rooms; and to control stock, in a very easy-to-use manner; and to schedule and record repair and maintenance work; and to support administration by, for example, printing breakfast lists and room cleaning lists."

[Of course, those "and"s are the obvious giveaway. I put them all in purposely; but they might well be implicitly there and a bit harder to spot. You may have had more. The initial introduction did mention banqueting and conferencing, which might well be within the interests of medium-sized hotels. JD]

The mission statement does lack cohesion and focus, so we plan some packaging and form a mission statement for each package:

  • Guest
    • Booking -- To accurately and optimally book rooms
    • Billing -- To invoice for accommodation and sundries and record payments thereof
    • Scheduling -- To print, for example, breakfast room lists, room cleaning lists
  • Stock control -- To control stock in an easy to use manner
  • Fixtures and fitting -- To control maintenance tasks via repair requests, scheduling, reporting and completion

The ensuing mission statements are much more cohesive and focused.