Info. Sys. Answers Combo 1997-2000
Info. Sys. Answers Combo 1997-2000 |
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PART A Multiple Choice Items
Attempt all questions in this part. Each question is worth 1 mark. Each question has only one correct response. For each question select the response that is correct. Signify your answer by circling the label (a, b, c or d) of the correct response. If you change your answer, completely erase your original answer. Questions where two or more responses are selected will score no marks.
1997 PART A Multiple Choice Items
9. Which of the following best describes the top down systems development technique?
(a) At first, most of the components are implemented as stubs.
(b) Individual components are made first.
(c) Upper management controls the development process.
(d) The system is developed iteratively.10. Which of the following is not an Information System design tool?
(a) Entity relationship diagram
(b) Data flow diagram
(c) Structure chart (diagram)
(d) Gantt chartEND OF 1997 PART A
1998 PART A Multiple Choice Items
1. The following tools are used in the IT industry:
- Gantt Chart
- PERT diagram
- critical path analysis
- Microsoft Project
Which of the following people would use one or more of these tools for the task stated?
(a) A programmer to define the terms and objects used in a suite of programs.
(b) An analyst to determine if a system is “open” or “closed”.
(c) The project team leader to schedule the development of a new system.
(d) A database designer when normalising data.2. Part of a Management Information System (MIS) developed for a manufacturing company provides an enquiry screen to display sales volumes over the previous 8 quarters. It does this by extracting individual order details from the company database, then displaying the total quarterly orders in a bar chart.
Which of the following sentences best describes what is happening here?
(a) Data is being converted into information.
(b) Information is being converted into data
(c) This illustrates a “bottom up” design.
(d) This illustrates a “top down” design.3. Which of the following statements is always true about an open information system?
(a) An open information system is built as a series of objects which open when they receive a message from another object.
(b) An open information system has boundaries allowing the flow of data into and out of the system.
(c) An open information system has nothing hidden inside it.
(d) An open information system has no access security implemented.END OF 1998 PART A
1999 PART A Multiple Choice Items7. Which of the following incorrectly describes the relationship between information systems and management information systems (MIS)?
(a) A MIS is a system for managing an information system.
(b) An information system is a way of implementing a MIS.
(c) An information system may include a MIS as a component.
(d) A MIS provides information of a more strategic nature than does an information system.8. If you were developing an accounting system bottom up, the very first thing you might code would be:
(a) The system menu.
(b) A routine to calculate compound interest.
(c) The last item to be included in the system menu.
(d) A report for the auditors.9. Complete the following. Logical data flow diagrams are used to:
(a) Design communications networks.
(b) Outline computer algorithms.
(c) Document the information passed between parts of a system.
(d) Schedule project management tasks.10. Which of the following statements about distributed information systems is always true?
(a) A distributed information system uses a relational database.
(b) A distributed information system uses modems.
(c) A distributed information system has more than one CPU.
(d) A distributed information system uses computers from more than one manufacturer.11. Which of the following is included in data flow diagrams?
(a) File structures.
(b) Data structures.
(c) Process controls.
(d) Data stores.END OF 1999 PART A
2000 PART A Multiple Choice Items10. A computer based information system consists of
(a) computer, keyboard, monitor, hard disk and printer.
(b) people, procedures, data, software and hardware.
(c) input, processing, storage and output.
(d) planning, programming, organising and evaluating.11. Which of the following tools would be used to plan and keep track of resources within a system development project?
(a) Gantt Chart
(b) Logical Data Flow Diagram
(c) Structure Chart
(d) Entity-Relationship Diagram12. Which of the following may be classified as data?
(a) text
(b) pictures
(c) numbers
(d) all of the aboveEND OF 2000 PART A
1997 PART B Short AnswersQuestion 16. (3 marks)
Study the following extract from a newspaper article.
(Note: Not all of the article is reproduced here.)(a) Describe a strategy that you could use to determine if an organisation is likely to be affected by the millennium bug? (6 lines)
MILLENNIUM BUG TO BITE COMPANIES HARD At the end of the sixties a number of computer companies found that their computer programs were failing. On investigation, these companies found that the programmers had recorded the current calendar year as a single character—based on the assumption that the prefix will be “196”.
The programs worked well during the sixties, but with the arrival of 1 January 1970, the computer programs reported the current date to be 1 January 1960. Suddenly,
simple arithmetic calculations based upon the current date produced ridiculous results. Of course, this could not happen today, or could it? It is estimated that the “millennium bug” will cost commerce $500 billion to fix. A company has the “millennium bug” if any of its computer programs record the calendar year using only the final two characters.
We do not have to wait until 1 January in the year 2000 before witnessing the effects of the bug.
Some credit card companies have cancelled customers’ accounts as the company computer has reported that the credit cards were due to expire in the year 2000 and the program recorded this expiry year as “00”. Later, when checking the validity of credit transactions, those cards were deemed to have passed their use by date.
Companies that do not take action to eradicate the millennium bug….
Apart from the implementation of various "millennium bug detector" utilities on offer, the various systems could have the date and time set for just before midnight on 31 December 1999. At this stage, the opportunity exists for any repercussions to be observed within a controlled environment.
(b) What needs to be done to fix the millennium bug? (3 lines)
All code needs to be checked for definitions of date data types and arithmetic using them. Dates have to be converted to a 4-digit year.
Question 17. (3 marks)
The classical systems development life cycle may be outlined by the following sequence:
1. Preliminary investigation
2. Analysis
3. Design
4. Implementation
5. Maintenance(a) How does the preliminary investigation differ from the analysis? (4 lines)
The Preliminary Investigation focuses upon defining the nature and scope of the problem and outlining possible solutions with associated cost/benefit predictions...
...whereas within the Analysis phase, the current system is investigated and documented in detail.
(b) Some information systems professionals (“generalists”) have a broad but possibly shallow knowledge of a wide variety of technologies, whilst others (“specialists”) have a detailed knowledge of a limited area. During which stages of the systems development life cycle would each type of professional be most usefully employed? (2 lines)
The “generalist” would be employed most usefully during Feasibility and/or Analysis.
The “specialist” would be employed most usefully during Design and/or Implementation.
Question 18. (2 marks)
When the school canteen needs to order food supplies it creates an order in triplicate using the suppliers’ price list file to determine who the order is to be sent to. One copy of the order is filed and another sent to the Accounts Department in the administrative building.The following data flow diagram was intended to describe this system, but was poorly constructed. Identify, by writing notes on the diagram, four errors in the data flow diagram.
Any four errors, including:
vectors not labelled;
vectors labelled incorrectly
incorrect symbol for file and/or source
vector NOT coming from (or going to) a process.Question 19. (4 marks)
To what extent would you describe each of the following as an information system.(a) A television set (working) (6 lines)Although a television set can be a source of data, it does not qualify as an information system because it lacks interactive capabilities, beyond selecting a channel to view. There is no way for the user to request particular information.
(b) An automatic teller machine (6 lines)
An ATM (automatic teller machine) may be used to obtain current account balances and perform simple maintenance (check balance, deposit, withdraw, transfer). Since these actions are at the command of the user, it qualifies as an information system.
END OF 1997 PART B
1998 PART B Short Answers
18. List four methods a systems analyst might use to gather data about an existing information system. [2 marks]
- interviews
- sampling
- questionnaires
- observation (including work shadowing)
- written documents
19. List the steps of the traditional systems development life-cycle. [1 mark]
- 1. Preliminary investigation, also called Feasibility Study
- 2. Analysis
- 3. Design
- 4. Implementation
- 4a. Testing
- 4b. Installation
- 5. Evaluation and Maintenance
- (Note: variations occur, depending upon the textbook used.)
20. Research shows that over the lifetime of most applications the cost of maintenance greatly exceeds that of development. It is suggested that if programs could be developed without any errors, the cost of maintenance would be zero. Give one reason why this statement is false. [1 mark]
Maintenance is not just fixing errors. It also covers enhancements required by changing business practices and modifications enforced by a changing environment.END OF 1998 PART B
1999 PART B Short Answers
19. A project has been estimated to take 10,000 hours of work. Assuming that a person will work for 2,000 hours in a year, this would imply that the project would take about 5 years if staffed by one person. Alternatively, one might employ 20,000 people to complete the project in 30 minutes. If the project were an information systems development project, neither of these approaches would be reasonable. Explain why, giving two reasons in each case. (2 marks)
5 years is too long for users to wait for an IT system.
Unwise to rely on a single person (could die or leave).
Requirements will change over this period of time.
Technology will change over this period of time.Time cannot be divided like this—you must allow time for communication.
Not everything can be done in parallel. (Some things can only be done after others are complete.)
Does not allow for training time.
No physical space for so many people to work together.20. One of the phases of the life cycle approach to information systems development is to gather the user requirements. Typically this is done by user interviews and culminates in the “requirements specification” document. How are the requirements determined using the prototyping approach? (2 marks)
In the prototyping approach, the initial guidelines are determined by answers to broad questions but are then further refined through the iterative approach of use and modify.21. Software maintenance of computer systems frequently costs more than the original development did. There are three classes of software maintenance. Describe two of them. (2 marks)
Corrective maintenance—bug fixing of program errors.
Enhancement maintenance—user driven changes as users gain more sophisticated and have more requirements e.g. “hot” keys or new formats for screens.
Adaptive maintenance—environmental change as the system’s environment changes e.g. introduction of GST, reporting standards etc.22. Many people think that computer systems and information systems are the same thing. (2 marks)
(a) Give one example of a computer based system that is not an information system.robotic arm, computer game(b) Give one example of an information system that is not computer based.
telephone book, newspaper classified advertisements24. What is the difference between analysis and design? (2 marks)
Analysis documents the user requirements.Design finds the best way to fulfil the user requirements within the constraints of the project.
END OF 1999 PART B
2000 PART B Short Answers
25. What activities may users be involved in during the following phases in the system development process? Describe two activities in each phase. (2 lines for each phase) (2 marks)
Systems Analysis: Talk about the problems of the old system, discuss their requirements for the new system,
etc. 0.5 mark for each activity.
Implementation: If on the project development team, may do some training, otherwise will be trained to use the system,
etc. 0.5 mark for each activity.
26. Give examples of two different jobs for an information technology professional, and briefly describe what each job involves. (4 lines) (2 marks)
Systems Analyst
Programmer
Project Leader
Database Administratoretc. 0.5 mark each job and
0.5 mark each description.27. When a customer rents a video at their local video store, they first tell the assistant their membership number. The assistant enters this number into the computer and confirms their name and address details. She then swipes the bar coded identification number on the video with a wand and details of the rental transaction are recorded in the rentals file.
The following Logical Data Flow Diagram (LDFD) describing the system is poorly constructed.
Identify four errors in this LDFD. (4 lines) (2 marks)
“Rentals” should be a process and therefore must have a verb.
No direction of data flow for “membership_number”.
Data flow in wrong direction for “customer_details”.
“VIDEOS” should not be an external entity.
No data identified on two separate vectors.etc.
END OF 2000 PART B
1997 PART C Extended Answers
Question 27. SuperShopper Supermarket Chain (19 marks)
The SuperShopper supermarket chain operates in the following manner. All produce is supplied from the central depot. Every item sold is labelled with a unique code, which is entered by the checkout operator along with the quantity. A disk file from head office contains a record for every item code giving item description and recommended price. Each supermarket is run by a manager who can choose to charge the recommended price or some other price to suit local conditions. Typically this is used to offer "specials". The computer system therefore keeps a separate file giving special prices for selected items. The manager will maintain this file by adding and deleting items from it. When a customer reaches a checkout, the item code will be checked against the specials file and the price in that file used. In the event that there is no item of that code in the specials file, the price from the head office file will be used. The customer gets a receipt containing the item descriptions, quantity and price.
(a) (12 marks)
Draw a data flow diagram covering the operation of this system. (space of 3/4 page)
(b) (3 marks)
This system works well for pre-packaged items, which are all the chain currently sells. However, the possibility of expanding the range to fresh food is being considered. In particular it is felt that there would be a market for fresh fish. The customers would choose a fish, possibly even catch one from a tank, and take it to the fish counter for scaling. One anticipated difficulty lies in identifying the type of fish, since the staff may not have the required expertise, and prices of different species might vary widely. It is proposed to develop a computer system to identify fish at the checkout, possibly by capturing an image or by some scientific measurement.
For a system of this nature, which development methodology would you use? Give reasons for your answer. (6 lines)
(c) (4 marks)
Until the automatic computer identification system is working adequately, the company is prepared to employ fish experts to identify the fish (visually). It is not possible to have an expert at every supermarket.
Describe the equipment required to enable the experts to identify the fish for the checkout staff. (12 lines)
END OF 1997 PART C
1998 PART C Extended Answers
Question 30 [20 marks]
Honest John’s Bargain Emporium
Honest John's Bargain Emporium sells a variety of goods very cheaply. To save costs, they use a manual procedure for handling credit card purchases.
The customer first presents the goods and card to the clerk.
The sales clerk checks the card against a list of stolen cards. The police maintain this list. If the card is on the list, the card number, dat and time are passed to the police. If the card is not on the “stolen” list the sales clerk uses the credit card to imprint a credit slip which is then updated with the date and the total price of the purchase.
The credit slip is then passed to the customer who signs the slip and hands it back to the clerk. The clerk checks the customer's signature against that on the back of the card and if satisfied, records the details of the purchase into the sales register and hands over the purchased goods with a copy of the credit slip to the customer. The original signed credit card slip is placed beneath the cash and cheques in the cash register drawer. At the end of each day, all the credit slips are collected, collated and delivered to the Bargain Emporium's credit company.
If the clerk is not satisfied that the signatures match, the customer is notified that the purchase is refused and the credit card will be handed over for investigation. The credit card and the credit slip are forwarded to the police.
(a) The following symbols are used in data flow diagrams. Name each symbol. (4 lines) [2 marks]
circle or ellipse represents a processsquare or rectangle represents an external entity (source/sink, source/destination)
arrow represents a vector (data flow)
open ended rectangle represents a temporary data store (file)
(b) The analyst first produces the following data flow diagram:
Give four reasons why this diagram is wrong. (4 lines) [2 marks]Goods are not data.
The system has no processes between source and sink.
No police.
No credit company.
No associated data flows to these last two items.(c) An improved top level data flow diagram is shown below.
(ii) State two advantages and two disadvantages of using the prototyping approach rather than the life cycle approach. [2 marks]
Advantages:
- user gets to see the system earlier.
- excellent for users who do not know exactly what they want their new system to do.
- users feel a greater sense of “ownership” over the new system.
- there’s a much greater chance of matching the user’s requirements.
- users gain training during the system development.
- faster.
Disadvantages
- a large amount of user intervention is required.
- it’s difficult to know when to stop the iterative process.
- prototype becomes the system too early due to user insistence when it really should be rewritten for efficiency and quality assurance.
END OF 1998 PART C
1999 PART C Extended Answers29. Ettamongah Amateur Dramatic Society (12 marks)
The Ettamongah Amateur Dramatic Society has its own small playhouse theatre. The theatre consists of 26 rows (A-Z) of numbered seats. Due to a generous government grant, the Dramatic Society is able to produce plays for the local community citizens at no charge. However, the Dramatic Society insists upon the citizens reserving their seats for each performance. This reservation activity is conducted by the box office.When a new play is scheduled, the Dramatic Society provides to the box office seating plans for each performance which indicate the seats available for the community.
To reserve seats, the citizen goes to the Dramatic Society’s theatre box office and requests from the box office manager a number of seats for a particular performance. The box office manager consults the seating plan for that performance and offers the citizen a number of options. When the citizen selects a seating option, the box office manager updates the seating plan by crossing off the seats taken. The manager then produces tickets for the citizen that details their reserved seats for the relevant performance.
Occasionally, the Dramatic Society will require a report from the box office manager that gives details of the seats reserved for particular performances.
Construct a logical data flow diagram (LDFD) describing the operations of the box office. (12 marks)
Even though the question doesn’t ask for it, you really should draw up a table first, something like this:
Sources and Sinks
Vectors
Processes
Data Stores (files)
Citizen
Dramatic Society
Number of seats required
Performance date
Seating options
Performance available seats
Performance seats taken
Available seats for new performances
Selected seats for performance
Tickets (details)
New performance seating details
Date of performance
Reserved seats for performances
Performance reservation report
Providing seating options
Issuing tickets
Adding new performance seating plan
Generating management report
Performance seating plans
...but, this time, you only get marks for the LDFD, which should be something like this:
END OF 1999 PART C
2000 PART C Extended Answers
30. (19 marks)
SilverBlink Fan ClubSilverBlink is a four-person rock band with a well-established fan club that has been operating for many years. The partner of one of the band members is the president of the fan club and has efficiently conducted many tasks for years, including sending out newsletters to members and selling CDs direct to the public at cheaper rates. However the fan club has recently grown rapidly and the rock band decides to employ someone to run the business full-time. SilverBlink have also been convinced of the profitable markets that are provided by e-commerce and decide to conduct all their fan club business over the Internet. They employ Alex who is a wizard at web page construction to design the web site for The SilverBlink Fan Club. Alex is multitalented and is also required to process the applications for membership, post out newsletters and manage the CD sales and bookkeeping functions. Alex is responsible to the club president.
Members of the public now register for membership of the fan club online. They fill in a secure electronic “application for membership” form, supplying their name, email address and postal address details for the regular newsletter mail-out. Fans who wish to make future purchases online must also supply their credit card number at their time of registration. The fan’s name and credit card number are supplied to their credit authority that authenticates credit card details. All the details of the new fan club member are then recorded in the members file. It takes 24 hours for the application to be processed and the new fan club member is notified by email and informed of their membership number.
Fans prefer to read the SilverBlink News in hard copy and on the 15th of each month they are notified by email that their newsletter has been mailed out to them. The members look forward to receiving the newsletter and frequently buy the CDs that are advertised both in the newsletter and online.
All purchases are done online. A fan completes an online order form supplying their membership ID and the name of the CD they wish to purchase. They do not have to supply their credit card details again because this has already been authenticated at the time of registration. Member details are validated and the database is checked to see if the CD is in stock and to obtain its current price. When the CD is in stock, a record of the purchase is made and the stock file is also updated. A receipt is packaged with the CD ready for collection by the courier.
Each month a sales report is compiled and forwarded to the president. The number sold for each CD and total income from sales is reported.
(a) Complete the Context Diagram that has been started below, to show the overview of the SilverBlink Fan Club System. (one page) (6 marks)
Note: Although the question doesn’t ask for it, you should really draw a table (for yourself) so that you can see clearly which entities are sources and sinks, which data flows along the vectors, where the data is stored, and what processes are being carried out.
Entities
(Sources/Sinks)Processes Data Flows
(Vectors)Data
StoresFan
Credit_Authority
President
applying
notifying
purchasing
packaging
compiling
name
email_address
postal_address
credit_card_No
membership_ID
mail_out
CD_title
authentication
current_price
record_of_purchase
No._of_CD_in_stock
receipt_details
sales_reportmembers_file
CD_DB
Now you can draw your context diagram
Note: Not everything in the table will show up in the context diagram.
The context diagram doesn’t show any vectors within the system. It only shows the vectors that carry data out of the system or carry data into the system. You still need to keep these internal vectors in mind for when you draw the LDFD.If you think of (or find) something that you believe should be in your LDFD, go back to your table and add it there, first. Then add it to your context diagram (if relevant). Finally, add it to your LDFD.
(b) Decompose your Context Diagram into a Logical Data Flow Diagram (LDFD) that shows all the processes and data flows in the SilverBlink Fan Club System. (one page available) (13 marks)
1 mark for each fileEND OF 2000 PART C
2001 PART C Extended Answers
END OF 2001 PART C
