University of Toronto Textbooks are often not ordered in time for the start of classes But that s just a symptom So you ask the manager why Because we don t receive the booklists from instructors early enough Is that just a symptom of some other problem Scoping the solution so ask the instructors why Because the instructors aren t allocated to courses early enough Is that just a symptom of some other problem so ask the UG office why Two case studies Is that just a symptom of some other problem so ask the dept chair why Hotel checkout system Is that just a symptom of some other problem so ask the dept chair why Is that just a symptom of some other problem so ask the new recruits why Is that just a symptom of some other problem so ask U of Waterloo etc why How do you stop yourself from computerizing everything Decide the scope of the problem E g Bookstore example Scoping the problem How do you stop looking for bigger problems to solve Department of Computer Science Scoping decision I Tutorial notes Scoping your analysis University of Toronto Department of Computer Science Because we never know who s available to teach until the last minute Because there s always uncertainty about who gets hired sabbaticals etc Computer Books by Mail Because instructors we want to hire don t accept our offers early enough Because some other universities seem to wait for ages before making offers Because it takes our department a long time to reach consensus on hiring Is that just a oh wait maybe we can develop a decision support system for faculty hiring at U of Waterloo and that will help us get our textbooks for the start of class 1 Mylopoulos and Easterbrook 2002 University of Toronto University of Toronto Department of Computer Science How to scope the problem Difficulty Decide the scope of the solution Say you decided that delay in processing booklists from instructors is the right level of problem to tackle You can keep on tracing root causes forever if you re not careful Approach Department of Computer Science Scoping Decision II Every problem can be seen as as symptom of some other larger problem 2 Mylopoulos and Easterbrook 2002 So let s computerize the submission of textbook forms from instructors ask yourself these questions But while we re at it Is there a reasonable expectation that this problem can be solved it would help if we also computerized the submission of orders to the publishers and of course independently of the larger problem we ought to computerize the management of book inventories too so we can quickly check stock levels before ordering new books Is there a reasonable expectation that solving this problem will help without also solving the larger problem and in that case Is this a problem that the stakeholders want solved we might as well computerize the archives of past years booklists so that we can predict demand better do the local experts think this problem is the one that matters Is this a problem that someone will pay you to solve and therefore Hint a feasibility study should quantify the return on investment it would also make sense to provide a computerized used book exchange because that has a big effect on demand for new books and then of course there s oh wait this is going to cost millions Bookstore manager tell me again how this automated used book exchange will help me order books faster Mylopoulos and Easterbrook 2002 3 Mylopoulos and Easterbrook 2002 4 1 University of Toronto University of Toronto Department of Computer Science How to scope the solution Example A Hotel Checkout System Difficulty It s hard to decide when to stop adding extra bells and whistles Approach select among alternatives carefully independently of all the other options Is there a reasonable expectation that implementing this alternative will help to solve the original problem customers leaving without paying some charges sometimes customers are double billed because they declare a certain charge for which they have already been billed Is this a solution that the stakeholders can live with do the local experts think they would use all these functions management expects business to grow Is this a solution that someone will pay you to build a major extension to the hotel is being built manual updates of customer records will become problematic Hint a feasibility study should quantify the return on investment for each alternative So they d like continuous on line updates of customer accounts from the hotel catering service responsible for room service the pay TV system charge a customer as soon as she starts viewing a movie and the hotel restaurant assume there is only one 5 University of Toronto Hotel management want to change it because there are often billing errors such as without also having to address other aspects of the problem Mylopoulos and Easterbrook 2002 room charge per day room service charges for such things as snacks delivered to one s room room movie charges if the customer uses the room s pay TV restaurant charges if the customer dines in the hotel s restaurant and charges the bill to her room When the customer leaves she is supposed to mention any recent charges which are then added to the bill and the bill is paid in full Is there a reasonable expectation that this alternative can be implemented 6 Mylopoulos and Easterbrook 2002 University of Toronto Department of Computer Science Analysis Current system The customer s account is updated twice a day with charges including We could keep on throwing more technology at the problem forever Department of Computer Science Department of Computer Science Computer Books by Mail CPM What are the problems Current situation Established 12 years ago CPM s business has been to act as book jobber receiving orders from librarians for books about computers ordering the books from the appropriate publisher at a discount filling the order on receipt of the books from the publisher What are the alternatives Invoices are produced by a service bureau computer from forms filled out by CBM staff Business currently running at about 100 invoices per day each with average of 4 book titles and average value per invoice of 150 What are the selection criteria What recommendation would you make CBM Corp recently acquired by a holding corporation New management plans to expand the operation considerably improving service levels by holding stocks of the 100 most frequently ordered book titles allow all professionals not only librarians to order by
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