Last changed:
March 12, 2022 12:29 PM
Post Mortem Notes This is not a VCAA publication.
I do not speak for the VCAA, the IT examiners, or exam markers. I was not involved in the writing or marking of this examination. Extracts from exams are all Copyright © VCAA, and are used with permission. Use these post mortems at your own risk. I reserve the right to change my mind completely, at short notice, about anything I've said here. Suggestions, discussions and corrections are welcome. Questions look like this. |
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Last changed: March 12, 2022 12:29 PM Examiner's comments added 15 April 2016 |
The Post Mortem Awards |
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The SCHMACKOS award is given to questions that are a complete dog's breakfast. |
The Sick Dog Award |
The exciting Illiteracy Award. |
The Post Mortem Stamp of Approval, for questions I like. |
INFORMATION TECHNOLOGY:IT APPLICATIONSWritten examinationThursday 12 November 2015 Reading time: 11.45am to 12.00 noon (15 minutes) QUESTION AND ANSWER BOOKStructure of book
Students are NOT permitted to bring into the examination room: blank sheets of paper and/or white out liquid/tape. No calculator is allowed in this examination. Materials supplied
Answer sheet for multiple-choice questions. Instructions
Check that your name and student number as printed on your answer sheet for multiple-choice questions are correct, and sign your name in the space provided to verify this. All written responses must be in English. At the end of the examination
Students are NOT permitted to bring mobile phones and/or any other unauthorised electronic devices into the examination room. |
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Examiner's report - general comments (the emphasis was added by me) |
Students were able to design screens for online transactions, taking into account the particular needs described in a given scenario. Responses demonstrated that students were aware of a wide range of layout conventions and design elements. They were able to explain, in brief annotations, how these enhanced the effectiveness (clarity) of communication. In Question 5 annotations were added to screen designs to explain how, for example, the central placement and hierarchy of text helped to establish the identity of the company, encourage users to participate in T-shirt design activities and buy products. Students demonstrated some understanding of the purpose and process of normalisation. When presented with a flat file data table, most students provided partial solutions consistent with the third normal form (3NF); however, many students did not score any marks for this question. Responses that focused on the specific requirements stated in the question and that provided examples appropriate to the given scenarios were awarded high marks. It is worth noting that questions couched in terms of efficiency or effectiveness require responses that address one or more of the components of these two qualities. To address efficiency, for example, a response needs to include an example of time, cost or effort. To address effectiveness, a response needs an example of improved accuracy, timeliness, completeness, readability, attractiveness, accessibility, relevance, usability or clarity of message. It was clear that students understood the roles of various procedures and equipment used to protect data and information within security and backup strategies of an information system. However, many students confused evaluation with testing. Students drew on their experience with their chosen software application to solve problems. In Question 10, for example, some students created a wide variety of innovative and thoughtful RDBMS and spreadsheet designs to solve the problem of storing and manipulating data shown on a mobile phone screen. |
Question A1 |
A local community uses a proxy server because proxy servers
Answer should have been D. The examiners said A. A proxy server is a computer/server that acts as an intermediary between a client and a web resource. The client connects to the proxy server, which then requests a connection, file or other resource on a different server (e.g. a website). An anonymous proxy hides the client's real internet address (IP) from the external resource. Not an easy question to begin with. I'd say many students would be flummoxed by this. Anyway - what is this "local community" bit? Do they mean an online community? Or is it a suburb somewhere? Very strange. Official answer was A. Work that one out if you can. Very weird. The examiners said: A proxy server is an intermediary server that provides access to online resources from other servers. Unique IP addresses are allocated by the Internet Assigned Numbers Authority (IANA). 13% of the state got it right. 65% said D, as I did. |
Question A2 |
The main purpose of a website that publishes the findings of space research is
Answer is C. Straightforward enough. The examiners said: nothing. 87% of the state got it right. |
Question A3 |
A carpet company is introducing a new information system to manage quotes, sales and carpet stocks at its 15 stores. All store managers need to learn how to use the forms for data collection, the functions available for data manipulation and the reporting formats. They will then be able to provide detailed instructions to sales staff before the new system is introduced.
Answer is A. A tutorial is an in-depth teaching tool. But hang on a potato-digging minute! Since when is documentation the same as training? The examiners said: Managers need both an overview of the new system and experience in using the new forms associated with all stages of the input-process-output cycle. A tutorial will meet both needs. 71% of the state got it right. |
Question A4 |
Which of the following are non-technical constraints on a solution?
Answer is D. The second items in options A, B and C (file sizes, file formats, bandwidth) are all technical constraints so they can be ruled out. Only option D has two items that are both non-technical. The examiners said: nothing. 74% of the state got it right. |
Question A5 |
Sammy Real Estate has offices in 10 suburbs and 15 country towns. Its staff need to send videos of properties and customers’ financial details between offices.
Answer is B. The only wireless connection that could reach across suburbs and to country towns would be microwave, and that's unfeasibly expensive for a moderate-sized company. Coaxial cable has not been used for networks for a long time. Fibre optic cable is very hard to tap without being noticed, and file encryption would make files unreadable to unauthorised people. Still, laying dedicated fibre optic across entire suburbs and into the country is not exactly realistic either. A real solution would be to set up a VPN and use the standard internet infrastructure. The examiners said: nothing. 61% of the state got it right. 21% said A. |
Use the following information to answer Questions 6-8. A zoo keeps a relational database management system (RDBMS) to store data about its animals, the enclosures they are kept in and the staff who act as keepers. The field names for the Cats and the Keepers tables are shown below. |
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Question A6 |
In the Cats table
Answer is D. In the Cats table, CatID is the key field, so by definition it must be unique. Rule out options B and C. It's weird that the cat's colour is recorded, but not its species! Or is it a zoo for domestic pets? The examiners said: nothing. 56% of the state got it right. 34% said A. |
Question A7 |
Each cat has a keeper responsible for it. Each keeper is responsible for up to four cats. The relationship x-to-y shown above is
Answer is C. Tip 1: Any relationship line leading to a key field (e.g. KeeperID in the Keeper table) must be the "one" end of a relationship. Tip 2: You will never see a many:many relationship in an exam. Actually, you won't even see such a thing in a real database. I dare you to try to find a way to define a many:many relationship in your RDBMS. The only way to make one is to create an intermediate 'line' table between two other tables and create 1:many relationships between the 3 tables. Tip 3: you'll hardly ever see a one:one relationship either. They are pretty useless. The examiners said: nothing. 64% of the state got it right. |
Question A8 |
EnclosurelD in the Cats table can be used to retrieve data effectively because
Answer is D. The Enclosures table is not provided, but if it existed it would have a list of unique enclosure IDs with data corresponding to each enclosure. The examiners said: nothing. 55% of the state got it right. 22% chose C, 17 chose A. |
Use the following information to answer Questions 9 and 10. |
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Question A9 |
Primary keys could be represented by the labels
Answer is C. It can't be A because "V" is not an attribute. You have to assume that the underlined letters represent key fields because in the case of 'Buses' there are two attributes that are not underlined, and they could both not be primary keys, suggesting that x - and underlined attributes elsewhere - must be keys. The examiners said: nothing. 91% of the state got it right. |
Question A10 |
The labels w and v represent, in that order
Answer is A. Read it as "Mechanics <does something to> buses" and "Drivers <does something to> buses". Too easy. The examiners said: nothing. 89% of the state got it right. |
Question A11 |
Bank customers can have a car loan if they have at least $5000 in savings or if they are employed and not paying rent.
Answer is D. "At least $5000" rules out B. The examiners said: nothing. 87% of the state got it right. |
Question A12 |
The most effective way to store records that are no longer actively used but must be retained is to
Answer is C. It describes the process of archiving. Option A is referring to an incremental or differential backup. The examiners said: nothing. 55% of the state got it right. 31% went for D. |
Question A13 |
An online survey has been designed for the members of a music society to rank their favourite music genre: Answer is B. The radio buttons force the entry of one - and only one - valid option. Unfortunately, it still allows more than one genre to be given the same ranking, so it's really just the least-worst option. Option A would achieve nothing. Option C allows any type or range of values to be entered. It still irks me when data entry controls are called 'validation techniques'. The examiners said: nothing 55% of the state got it right. |
Use the following information to answer Questions 14-16. The Belfield Theatre Company (BTC) is a successful suburban amateur theatre group. In recent times, however, its audience numbers have dropped, resulting in declining income. If this continues, the quality of the plays put on by the BTC will be affected. Therefore, the BTC has set a three-year goal of maintaining its production quality, while at the same time reducing costs. The BTC uses an information system to record all its ticket sales. |
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Question A14 |
The chart above would best assist the committee to make
Answer should be C. But the examiners said it was B. It's not operational - a day-to-day decision that keeps an organisation running. It's not strategic - a significant, long-term, potentially dangerous, expensive, disruptive, ethos-changing, company-wide decision. "A three-year goal of maintaining its production quality, while at the same time reducing costs" is strategic. It's tactical - designed to support the achievement of the bigger strategic goal. So it's C or D. Planning the performance schedule would help them achieve their strategic goal. Official answer was B, believe it or not. The examiners said: The committee is planning the schedule for 2016 and beyond. A strategic decision will apply for more than a year. Since when have the examiners given a 12 month time frame for a strategic decision? NEVER! 30% of the state got it right. 43% chose D. |
Question A15 |
At what stage of the problem-solving methodology would the specific data requirements for recording attendances be identified?
Answer should be B. But the examiners said it was A. The PSM description in the study design says that "Analysis involves: Determining the solution requirements. What information does the solution have to provide? What data is needed to produce the information?" The study design is not just for teachers. Kids should read it too. Official answer was A. Really?? I'd say that 'determining what data is needed' is the same as 'identifying specific data requirements', wouldn't you? For the record, I am aware that the 2015 study design said on p.15 that, "The solution design typically involves identifying what specific data is required" but the difference between this and "What data is needed to produce the output?" in analysis relies entirely on the word "specific", which is not defined.
Questions that rely on one undefined word in the study design are little more than petty quibbling, IMO.
A fairer question would have been, "In which stage of the PSM is it determined how data will be named, structured, validated and manipulated?"
I'm done now.
The examiners said: The study design states that design involves ‘identifying what specific data is required’ (page 17). 23% of the state got it right. 61% went for B, as did I. |
Question A16 |
The BTC is considering preparing a weekly report of performance attendances in a table. Answer is B. The examiners said: The Attendance data is numeric and is right aligned. The Time heading is text and is left aligned. These are the most appropriate conventions for the data. 43% of the state got this right. 34% chose D. |
Question A17 |
Which set of design tools best represents relationships in a website?
Answer is B. The study design says on page 17 that... "Typical design tools used to show relationships include storyboards, site maps, entity-relationship diagrams, data flow diagrams, structure charts, hierarchy charts, context diagrams, use cases." The glossary (page 13) says that design tools is defined as "Methods for representing the functionality and appearance of solutions. Tools to represent designs include data flow diagrams, entity-relationship diagrams, hierarchy charts, data dictionaries and data structure diagrams, object descriptions, flowcharts, pseudocode, input-process-output (IPO) charts, structure charts, annotated diagrams/mock-ups, storyboards, site maps, layout diagrams, use cases, context diagrams. The choice of tools is nature of the solutions." So option B is true - storyboards and site maps are listed. But since storyboards and sitemaps are specifically related to websites, and the other tools are arguably relevant, B is the stronger answer. The examiners said: Storyboards provide a visual representation of individual web pages and site maps show the relationships between those web pages in the whole website. Together they provide detail and an overview. 31% of the state got it right. 35% chose C. |
Question A18 |
Company A has a website to promote and sell its products. Its network includes file servers, printers and workstations.
Answer is A. The company that owns the data is responsible for securing it. The examiners said: nothing 60% of the state got it right. |
Question A19 |
The best device to prevent external electronic threats from entering a network would be
Answer is A. A firewall is protective hardware (e.g. in a router) or software (e.g. Windows Firewall) that controls the entry of data into a network, and monitors which software transmits data from the network. The examiners said: nothing 82% of the state got it right. |
Question A20 |
A cricket club has introduced a strategy to manage the disposal of players’ data.
Answer is D. Option A is just weird. The examiners said: Disposal of players’ data by overwriting it with new data means the application software and system software remain. If the disk is reformatted all data and software are removed, not just one player’s record. As part of a management strategy to dispose of players’ data, overwriting is more practical than deleting and reformatting the hard disk. 41% of the state got it right. 44% chose D. |
END OF SECTION A |
Overall - a pretty difficult section A. Much more demanding than in previous years. I predict a rather poor average performance by students. |
SECTION B - Short answer questionsJump to Section B question 01 | 02 | 03 | 04 | 05 | 06 | 07 | 08 | 09 | 10 | 11 [x lines] indicates how many ruled lines were provided on the paper for the answer |
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Answer all questions in the spaces provided. |
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(1 mark) |
Question 1 State one reason for a sports club to have a closed section on its website. 1 mark [1 line] So its registered members can discuss relevant and potentially sensitive issues without scrutiny or interference from anonymous outsiders. Most students stated one reason for a sports club to have a closed section on its website. State average - 0.8/1
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(6 marks) |
Question 2 An employment agency performs a weekly full backup of client records to an on-site tape media and a nightly incremental backup to the cloud.
Tip - be sensitive to little parts of the question such as the bit about "nightly incremental backup to the cloud". Each word has its own implications. Words in exam questions are not added for decoration. Ask yourself why that particular word was added. That's why I used dot points and bolding of key words to make the separate parts of the answer clearer. Our first award for this post mortem - for illiteracy. "an on-site tape media". "Media" is plural. It should be "an on-site tape medium" Responses to this question indicated that students understood the difference between full and incremental backup strategies. Most students gave one reason for the use of a strategy, either in terms of the location and timing or the choice of storage medium. Students who explained each strategy in terms of location, timing and media received high marks. Examples of responses that received marks are shown in the table below.
State average: 3.5 / 6 |
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(5 marks) |
Question 3 a. Describe one advantage to ViteHealth of offering online shopping. 1 mark [2 lines]
Responses that identified an advantage of online shopping directly for the ViteHealth business received a mark. Students who described an advantage for the customers of ViteHealth and who then explained the subsequent benefit for ViteHealth also received a mark. Students did not score a mark if they only described an advantage to the customer. Examples of correct answers included: State average: 0.8 / 1 b. Recommend two techniques that ViteHealth should use on the updated website to protect the rights of customers supplying data online. Justify each recommendation. 4 marks
Many students satisfactorily recommended and justified two techniques that ViteHealth should use to protect the rights of customers supplying data online. State average: 2.8 / 4
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(4 marks) |
Question 4 Michael is designing a prototype website. He can use one of two image files for the front page. File A is 2 MB and in BMP format. File B is 60 KB and in JPG format. a. Which image should Michael use? Justify your choice. 2 marks Image JPG Justification Compared to BMP, it's much smaller, faster for viewers to download, compatible with all browsers, and still of excellent quality. Most students selected the 60KB File B in JPG format. They justified their choice by explaining that the smaller file loaded faster than the larger file, or that the JPG format is widely used on websites whereas the BMP format will not load on all browsers. A small number of students noted that the BMP format would provide a better quality image. These also received a mark. State average: 1.8 / 2 b. Explain how Michael could test that he has made the correct choice of image. 2 marks [4 lines] He could put both images on the webserver and time how long it takes to download each one. He could compare each image onscreen to judge their relative quality. Responses that described a plan to compare the load times of each image received marks. High-scoring responses included: ‘Michael could use each image in his website and compare how quickly each loads’ and ‘Michael could see if each loads’. State average - 1.3 / 2 |
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(11 marks) |
Question 5 A web designer is given a brief by Choices@T-shirts to design a website that will allow international customers the opportunity to purchase from the existing range of T-shirts. In addition, customers will have the option of designing their own T-shirts. Once an order is placed, customers will be able to log in and track their orders. The website must also provide space for Choices@T-shirts’ contract designers, who work remotely, to collaborate on the design of new T-shirts. a. In the space provided [half a page of graph paper], design the home page of the website to meet the needs of Choices@T-shirts. Your design must include an example of each of the following:
These three examples must be clearly labelled on your design. 9 marks It will be interesting to see how the nine marks are dished out by markers. I'd be expecting so see: A layout convention
A link convention
A navigation design element
Other features to appear in the design
Responses that represented the required features listed in the design brief and that also annotated a layout convention, a link convention and a navigation design element, received marks. State average - 6.1 / 9 b. Explain how your chosen layout convention in part a. meets the needs of Choices@T-shirts. 2 marks [4 lines] A control to change the website's language allows international customers to purchase from the existing range of T-shirts This is a bit of a clue that something in their needs must be addressed in the layout convention you nominate.
I didn't like this question. Layout conventions on the homepage won't be relevant to most of the needs stated in the case study. Navigation would be relevant - sure. It helps people get to other pages to satisfy their needs. But layout on the homepage? No. Students were asked to explain how the layout convention they annotated in part a. met the needs of Choices@T-shirts. The answer shown below is typical of a response that received full marks. Many other conventions and associated explanations also received marks. State average - 1 / 2 |
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(4 marks) |
Question 6 A small bookshop wants to start selling books online.
Group this data into four tables (Tables 1-4). Add appropriate table names and fields so that the data collected from online sales conforms to third normal form (3NF) of a relational database management system (RDBMS).
Notes: 1. The author name is stored as "surname, initials" so splitting it into separate fields will not accomplish much. It's not likely that the two separate data will ever need to be addressed individually. 2. I did, however, parse the buyers' names since they may well be used as independent data e.g. in an email... e.g. in an invoice... e.g. in a postal address... At last! A sensible and realistic normalisation question that didn't ask stupid and unrealistic questions about how to escape from improbable 2NF problems that would never have arisen if the database had been designed properly with dedicated ID key fields. Such questions seem to me to be like 300 page self-help books along the lines of: "How to extract a carrot from your nose" In that way 2NF errors can never happen, or need to be artificially repaired in exams.
Most students received a mark for grouping the data into tables for: Books, Buyers, Authors and Orders. Further marks were awarded for reducing the fields to contain single elements of data and adding appropriately named primary keys. The response most frequently awarded full marks is shown below. Other answers that complied with third normal form (3NF) were also awarded marks. State average - 1.4 / 4
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(4 marks)
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Question 7 The graph below is derived from data reported in a survey about cyber security. The survey asked a number of companies to rate the effectiveness of five categories of security measures. a. Which security category is considered ‘very effective’ by the greatest percentage of companies? 1 mark [1 line] Network security controls. What is this? Kindergarten question time? Most students correctly read the graph and used the rating scale key to identify network security controls as the security category considered ‘very effective’ by the greatest percentage of companies. b. Identify a software security measure used to protect files in a network. 1 mark [2 lines]
The question asked about software, so don't discuss physical security, such as locked doors, barred windows, UPS etc. Most students identified a software security measure to protect files on a network. Answers included encryption to prevent hackers from reading data, firewalls to prevent unauthorised access to the network, and login and password software to check the access rights of those using files. State average - 0.9 / 1 c. Describe a procedure for effectively securing data communicated in a network. 2 marks [3 lines] Use an encrypted communication channel such as HTTPS (which uses SSL or TLS to encrypt web traffic) for data transfers, or Encrypt documents individually (e.g. with PGP) before sending them. Note the key word in the question: 'communicated'. Not 'stored'. I'm either not really happy with that question, or my answer. Perhaps the data-senders could also be quietly assassinated and buried in the concrete being poured for a new parking lot? Responses that described a procedure followed by users to secure data communicated on a network received marks. Login strategies that include regular changes to passwords or graphic indication of password strength; for example, help to prevent hackers from finding passwords by trial and error or by guessing. Other strategies that received marks included logging out before leaving a terminal, password-protecting or write-protecting files and not sending an encryption key in the same email as an encrypted file. Students needed to describe a procedure and identify a characteristic of effectiveness to gain full marks. State average - 1.1 / 2 |
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Question 8 HipDezigns is an online clothing company targeted at the 20-30-year-old market. Two friends, Kim and Gerry, regularly access the company’s website to check the latest fashions. What? Above it said "Kim and Gerry, regularly access the company’s website". a. Explain the ethical dilemma that arises from the data storage and monitoring practice used by HipDezigns. 2 marks [4 lines] The company wants to generate sales to improve their profit, but it's unethical to lie to customers about stock levels to stimulate them to buy. Whether it's also unethical to store customers' viewing history depends on whether the company has told visitors that it is storing that data, and why. Responses included ethical dilemmas affecting the friendship between Kim and Gerry, and the commercial relationships between: State average - 1.3 / 2 b. Outline the positive and negative effects of HipDezigns’ practice on either Kim or Gerry. Indicate with a tick if your answer relates to Kim or Gerry. 4 marks Kim □ Positive [4 lines] She (he?) is not being lied to or manipulated into purchasing impulsively. Negative [4 lines] None. Gerry □ Positive [4 lines] None Negative [4 lines] Gerry is being lied to, and deceived into believing the product is soon not going to be available. She may be led into buying impulsively. I really don't understand this question.
What are the positive effects of being lied to?
It's not as if Gerry benefits because she (he?) gets to own the product while Kim does not. Remember that the automated message is a lie. There is no shortage of stock. Kim could easily buy the product too. And what are the negative effects for Kim? She sees no lying message. She may or may not buy the item. So what? And were students supposed to discuss the morality of websites tracking their viewers' activities? Nearly every site does this with cookies or client databases. Why are ITA exams' ethical dilemma questions always so bad? Most students found it easier to find a positive for Kim who was not being cheated and a negative for Gerry who was being cheated. State average - 2.6 / 4 c. Propose a strategy for resolving the ethical dilemma explained in part a. 2 marks [4 lines] Don't lie to customers about low stock levels? This is worth 2 marks? Garth suggested that answers were possible if in fact there were only one item left, but nowhere in the case study does it say that the message would also be added if stock levels were actually low. The only stated trigger for the "only one left" statement was the third viewing. Strategies for resolving the ethical dilemma explained in part a. reflected the general nature of those earlier responses. Examples include: State average - 1.3 / 2 |
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(6 marks) |
Question 9 The following data table is used to record the details of the 4 L tins of paint kept by a decoration and renovation shop. Tins are identified by colour, cost, product code and the quantity currently in the shop. Why add the "4 L" detail? I bet a few kids would be trying to work out its meaning or at least its relevance. Paint table
a. Recommend a data type for Field3. Justify your choice. 2 marks Data type String/text. Justification It's alphanumeric and cannot be stored as a number. Most students suggested text as the data type for Field3 and stated that the recommendation was appropriate because data elements in that field were a combination of text and numeric types. State average - 1.4 / 2 b. Recommend effective names for each of the fields. 2 marks Field 1 strPaintColour Field2 floatPaintCost Field3 strPaintCode Field4 intPaintStockLevel Half a mark each? Hmmm. Students were asked to recommend effective names for each of four fields of a data table that represented paint tins stored in a shop. The most frequent response awarded full marks listed Paint_Colour, Cost_Per_Tin, Paint_ID and Quantity. Responses suggesting alternative names such as Quantity_Available and Paint_Code also received full marks. A significant number of students transposed Field2 and Field3 but were not awarded full marks. State average - 1.7 / 2 c. Explain the importance of using naming conventions in an RDBMS. Give an example to support your answer. 2 marks [4 lines] Names must be meaningful, informative and unambiguous. Meaningless names will soon mean nothing and will have to be looked up in a data dictionary to discover what they represent. Poorly chosen names (e.g 'IPSL' for Field4) may also be accidentally used instead of the correct field. Objects may be treated incorrectly, e.g. trying to store decimal places in an integer field. A name like 'intPaintStockLevel' uses Hungarian Notation ('int') to advertise its defined type, and uses CamelCase to make the words in the name more readable. Most students clearly explained the importance of using naming conventions in an RDBMS. Typically, they stated that it helps users to quickly understand the meaning of data they are reading, or it prevents confusion when users are creating queries within tables or relationships between tables. For example, a field name ‘Paint_Colour’ gives users a better idea of what the data represents than a fieldname such as ‘Field1’. Others described the process of joining two descriptive words, each starting with a capital letter, to create user-friendly field names. Many otherwise correct responses failed to include an example of a user-friendly fieldname or naming convention. State average - 1.3 / 2
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(13 marks) |
Question 10 The screen shown below presents some data about incoming and outgoing calls on a mobile phone. a. A spreadsheet or an RDBMS solution needs to be designed to store the data presented in the screen above so that the total cost of calls can be calculated. Complete the following table to indicate:
Ummm, spreadsheets don't HAVE data types. All they have is formatting of output. Hmmm. Does the 6 marks imply the examiners are expecting six fields?
The background of the table was filled with a grid. Why?? And spreadsheet column headings are very different to database field names - one can use spaces, and the data types are irrelevant. Would a student be penalised for giving the following answer? Because if you really created the spreadsheet, this is what the answer would be.
Students were asked to design a spreadsheet or database to store data about incoming and outgoing calls displayed on a mobile phone screen so that the total cost of calls could be calculated. Many students used Boolean (Yes/No) data types in their designs to distinguish between calls coming in and calls going out, and between voice calls and text messages. Most responses used a numeric (integer) data type for call duration. A frequently accepted correct response is shown below. Other designs and naming formats that solved the problem were also accepted.
A few students used call start-time and call end-time columns/fields with data type Date and Time. In these responses call duration was often calculated in the formula/query created to the answer in part c. These and other innovative designs were also awarded marks. State average - 2.2 / 6 b. Describe how you would identify the most frequently called number in one month once the design has been developed.
Spreadsheet □
Students were asked to describe how they could use their design to identify the most frequently called number in one month once the data had been developed. Students were required to constrain the call date to the last 28–31 days and the call type to out. Then they needed to count how many times each call number met both criteria and identify the call number associated with the maximum count. Responses that named reasonable fields, data types, functions and conditions to solve the problem received marks. For example: State average - 0.7 / 2 c. Explain how you would use your solution in part a. to calculate and display the total cost of outgoing calls if they are charged at $0.08 per minute.
□ spreadsheet
Students were asked to explain how they could use their solution to calculate and display the total cost of outgoing calls if they were charged at $0.08 per minute. They were required to constrain the call type to out, total the durations of those calls and multiply the total time by 0.08. They were also required to display the total cost. Responses that named reasonable fields, data types, functions, a condition and a display label to solve the problem received marks. For example: State average - 1.2 / 3 d. Recommend a strategy to evaluate the effectiveness of your solution in part a. 2 marks [3 lines]
The stuff in part a is not a solution: it's just a design for a data dictionary. Are students really meant to evaluate the effectiveness of field types? Did the examiners actually want students to TEST the effectiveness (accuracy) of the solution's CALCULATIONS in part b or part c, not EVALUATE the effectiveness of the DATA DICTIONARY in part a? I just know that some time next year I'm going to be VERY annoyed when the examiner's report comes out. Dammit. I can't wait until 2016. I'm getting annoyed right now. Here's my answer: Assuming you do actually mean 'evaluate the data dictionary' and not 'test a calculation' and assuming the effectiveness criterion is 'useability' you would refer to the data dictionary's access logs to see how often in the past 3 months database programmers had to look up the data dictionary to find the purpose or type of a database field. If there are few accesses, the field names appear to have been meaningful and useable. Sigh. Things were going so well up to this dog of a question. Students were asked to recommend a strategy to evaluate the effectiveness of their solution. A solution is evaluated after it has been implemented. Many students mistakenly recommended a strategy for testing their solution; that is, during the development stage. Marks were given for responses that stated that the strategy would apply after the solution had been up and running, and that through a survey or a complaints log the accuracy/timeliness/completeness or user-friendliness of records could be checked. Examples included: 'Have an online survey for customers after months. Ask if bills are accurate. Ask if their bill is easy to understand.' State average - 0.3 / 2 |
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(8 marks)
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Question 11 HiSkies is a parachuting club that needs an online application form for users who want to join the club and learn to skydive.
a. What is the best data type for the field that collects data on the acceptance of club rules? Explain why. 2 marks [4 lines] Boolean. It stores logical true/false answers, which is all that is needed to record acceptance. Also, Boolean data consumes very little storage space, so it is also very economical. Another question on data types? Haven't we done it enough in the previous question? Most students correctly recommended Yes/No (Boolean) as the data type for the field that collects data on the acceptance of club rules, stating that it ensures users can only enter one or the other of two options. A number of students recommended controls such as radio buttons. If they justified this as for a Yes/No (Boolean) data type they received a mark. State average - 1.3 / 2 b. Describe an electronic validation technique that could be used to ensure that a mobile phone number has the correct number of digits. Justify your answer. 3 marks Electronic validation technique [2 lines] This is shaping up to be another iffy question. The only validation techniques named in the study design are those in Software Development unit 4 - existence checking, range checking and type checking. No such techniques are named for ITA, except for a mention of 'proofreading' in the PSM discussion on page 17. (In Filemaker Pro) Validate the mobile phone number field using a formula, e.g. LENGTH(MobilePhoneNumber)=8. I don't know if MS Access or other RDBMS can do that. I only hope the examiners are not expecting students to refer to an input mask to force data to fit a pre-defined pattern. I am hoping this because input masks do not exist in Filemaker Pro or MySQL, and assuming knowledge of them would be prejudicial against students who used those tools. Justification [3 lines] Using a formula to validate fields in Filemaker is a very flexible way to automate all sorts of complex validation. Using an input mask forces users to enter characters in a particular format such as (_ _ _) _ _ _ _-_ _ _ _ Responses that described an input mask or similar designed to accept 10 digits spaced into correct groupings and with an appropriate error message received marks. Justifications included: it gives an error message if the length is wrong, and the spaces make it easy for users to read the number and check it as they enter it. Reponses that suggested restricting the number of digits to 10 also received a mark. State average - 1.6 / 3 c. Recommend a testing technique that could be used to ensure that the form collects the data required. [4 lines] Get someone to pretend to be an applicant and ask them to fill in the form several times. On each attempt they would deliberately leave one required field blank. If the database accepted an incomplete form, it would fail testing. In one form, the user would also attempt to enter more than 100 words about previous experience. The database should not accept anything after the hundredth word. An invalid date should be entered to test whether dates of birth are being appropriately validated. An attempt should be made to enter an email address without a @ or without at least one dot. Testing strategies that advised the developer to follow three or four appropriate steps generally received full marks. Typically, the steps were: State average - 1.3 / 3 |
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END OF QUESTION AND ANSWER BOOK |
Section B Overall - It was going quite well until the end, when the wheels started falling off. Too much on field naming and data types, IMO. Normalisation was handled sensibly. |
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Created 13 November 2015
Last changed: March 12, 2022 12:29 PM
VCE Applied Computing Notes © Mark Kelly 2001-
Original Content © Mark Kelly 2015 to
Images and questions © Victorian Curriculum
and Assessment Authority 2015.
Reproduced here with permission.