Nelson Information Technology VCE Units 1 & 2 · PDF file© Cengage Learning Australia 2011 1 Nelson Information Technology VCE Units 1 & 2 Test your knowledge answers . Chapter 1:

Information Technology VCE Units 1 & 2, 5th edition 9780170187466 © Cengage Learning Australia 2011

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Nelson Information Technology VCE Units 1 & 2 Test your knowledge answers

Chapter 1: From data to information

Purposes of information 1 What are the four main purposes of information?

The four main purposes of information are to inform, to persuade, to educate and to entertain.

Types of data 2 What is a data type?

A data type is a set of data with predefined characteristics.

3 What are four commonly used data types? Four commonly used data types are integer, floating point numbers, character and string.

4 Provide an example of each of the data types you have listed for Question 3. Integer – 10, -12, 99

Floating point numbers – 1.56, -0.123456

Character – A, m, @

String – 50 Park Street

Ways to identify relevant data 5 What can occur if information is produced from incorrect or incomplete data?

The information produced will be inaccurate and hence an unreliable source upon which to base a decision.

6 Why is it important to select relevant data? It is important to select relevant data so that the solution meets the desired purpose.

7 What two aspects need to be considered in order to select relevant data? The usability of the data and the characteristics of the targeted audience.

8 What are the properties of usable data? Suitability, reliability, accuracy, timeliness and freedom from bias.

9 How can entering an incorrect data type into a spreadsheet cause an error? Data of the incorrect type may not be able to be manipulated as required and hence an error will occur. Furthermore, the data that is incorrect may be ignored altogether, which will also cause mistakes in the solution.


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10 Why is it important to check the reliability of data? It is important to check the reliability of data because a lot of the information that is now freely available is unchecked and may not be accurate, or it may present views which are not widely accepted or recognised.

11 What is a common cause for data inaccuracy? A lot of data inaccuracy is caused during transcription when a user needs to input data from a written source.

12 How can the accuracy of a primary source be determined? Primary sources should be checked against the original data.

13 How can the accuracy of a secondary source be determined? Secondary sources should be checked against other secondary sources.

14 With an example, explain the importance of timeliness in ensuring the quality and usability of data. Data needs to be processed while it is current because decision-making should not be based on outdated data. Examples include a decision to take out a mortgage should not be based on interest rates that are more than a week old, and stock prices need to be continually updated so that potentially huge financial decisions are not based on out-of-date data.

15 What influences the introduction of bias into data? Explain each of these. Bias can be introduced by vested interest, timing, small sample size, bias through sorting and bias through graphic information.

Bias can enter data if the respondent to a survey or interview has a vested interest in the outcome of the research.

Data can be collected either too early or too late and this will introduce bias into the data collected. For example, you plan to survey a sample of the population for their views about Australia becoming a republic. The data you gather may be biased if, just prior to the survey being conducted, a royal tour takes place and there is extensive media coverage about the royal family. The timing of the data collection would introduce bias because it coincides with a significant event that distorts the responses away from those that would be provided at a different time.

Additionally, bias is not restricted to data gathered from surveys or during interviews. For example, suppose Qantas needed to decide whether to schedule two new weekly flights from Paris. The decision could depend on the demand for existing flights. If the airline collected data from bookings made over a four week period just before or during the Soccer World Cup to be held in Melbourne, then the data gathered would be biased. This data should not be relied on for making this decision because the influence of this event on customer demand is irregular and unlikely to occur again.

Small sample size can introduce bias as the data collected is not representative of the whole population.


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Sorting often causes bias as items at the top of the list usually attract more

attention. Graphic representations can misrepresent information if they are not sized

proportionally to avoid overstating or trivialising the importance of one of the variables involved. Graphic type, scale and size can all influence the way graphic information is interpreted.

16 What are the characteristics of an audience that should be considered to ensure that relevant data is chosen? Gender, special needs, age, status, location, culture and education level.

17 Explain how each of the audience characteristics identified in Question 16 can influence the data selected. Gender - Information should appeal to both genders or be specifically targeted at one or the other. When developing a solution for men, you should use smaller amounts of text and try to keep to one overall theme. When developing a solution for women, you should include more detailed information and images with stimulating text.

Special needs - Audiences with special needs must be catered for when designing a solution as conditions such as vision or hearing impairment, colour-blindness, dyslexia, cognitive difficulties, motor-control problems, age-related conditions or a combination of these make it difficult to access information and use a computer in traditional ways.

Age – As attention span varies with age, any product aimed at young children needs to involve a lot colour and movement to keep them interested, as they cannot maintain their attention for long periods of time. An older audience, on the other hand, has a greater attention span and can absorb more information, and usually require a higher proportion of text to graphics.

Status - Someone’s position in society or in an organisation relative to the position of others, determines their status. Usually, the more the senior the role, the more summarised the information will be. The tone for someone in a management role should be formal; the information should be condensed with short sentences. An authority in a field will expect longer, more technical, sentences and explanations of investigations and concepts. A general audience will require simple explanations and clear diagrams because they are usually reading outside their field of expertise. The general public require a more informal tone, with readable and easily understood information, written to a middle-secondary education level with simple illustrations and examples to demonstrate how the information can be applied to daily life.

Location - When considering the location of the audience you must include people who fall into the categories of global and remote. For global audiences you must ensure that you do not knowingly provide information that is illegal in countries where the information may be viewed. For remote audiences you need to consider that they may not have access to other sources. Remote audiences may find it


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difficult to act on information you provide as they may not have many resources at hand.

Culture - Information can enhance understanding between people of different cultures and it can also provoke tension, depending on its purpose. Language is a means by which people of different races can be catered for. Also, we must ensure that we do not alienate or offend anyone of a different culture by providing information that is unacceptable or offensive in their eyes.

Education level - Audiences who have a lower literacy level or have little or no experience in a particular field need more basic information, with simpler language, less jargon and more explanatory images. Audiences with a higher literacy level or more experience and skills in a particular area, can deal with more ‘technical’ or detailed language and you can assume a certain level of knowledge.

Types and purposes of graphic representations 18 What is a graphic representation?

A graphic representation is a pictorial diagram that shows interdependencies between variables.

19 List seven different types of graphic representations. Column charts, line charts, pie charts, bar charts, area charts, scatter diagrams and bubble charts.

20 Describe when each of the seven different graphic representations would best be used. Column charts – to present data changes over time or show comparisons between items.

Line charts – to show continuous data over time, set against a common scale. Line charts show trends in data at equal intervals.

Pie charts – to show proportional relationships and compare part of a whole at a given time.

Bar charts – to show comparisons between individual items.

Area charts – to emphasise the extent of change over time and draw attention to the total value across a trend.

Scatter diagrams – to show relationships among the numbers in several data series or give an overall impression of the relationship between two variables.

Bubble charts – are like scatter diagrams, but where the data series are displayed as circles (bubbles).


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Spreadsheet software 21 List five applications of spreadsheets.

Accounting, budgeting, financial analysis, statistical analysis and scientific applications.

22 Describe the following elements of a typical spreadsheet: worksheet, cell, cell reference, workbook. Worksheet – A table of columns and rows.

Cell – Intersection of a row and a column.

Cell reference – Location of a cell or group of cells.

Workbook – A collection of worksheets stored as a file.

23 What is the purpose of a conditional formula? To test whether conditions are true or false and make logical comparisons between expressions.

24 What is the purpose of a lookup formula? To return a value from a table (in a range) by looking up another value.

25 What is the difference between a function and a formula? Functions are predefined formulas that perform calculations by using given values, called arguments, in a particular order, or structure. Functions can be used to perform simple or complex calculations.

26 What is the advantage of sorting data? Sorting assists you in visualising the data more clearly so that it is organised and enables you to find the data that you need more quickly, which in turn enhances decision-making.

27 What is the advantage of filtering data? Filtering enables you to work with a subset of data, as it only displays the rows that meet the criteria you specify and hides the rows that you do not want visible.

28 Provide an example of when a person may use one of the mathematical functions of a spreadsheet. Any of: to keep a record of kilometres travelled for work for taxation purposes, to maintain a personal budget, or to calculate the amount of carpet required when renovating a home.

29 Provide an example of when a person may use one of the financial functions of a spreadsheet. Any of: to conduct profit analysis, to prepare quotations for customers, to prepare budgets and deal with investment and superannuation data.


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30 Provide an example of when a person may use one of the statistical functions of a spreadsheet. Statistical analysis to determine the average number of boys and girls within a school who study each of the VCE subjects.

Design elements 31 What are design elements?

Design elements influence the appearance and effectiveness of graphic representations.

32 List and describe each of the design principles. Proportion – Visual hierarchy of objects where the most important pieces of information have visual prominence.

Orientation – Direction and aspects of elements within a graphic representation.

Clarity and consistency – Clarity refers to how clearly information is presented and how well a user can differentiate between objects in a graphic representation. Consistency refers to the use of similar, recurring or conventional features.

Colour and contrast – Colour should make information clear, readable and attractive, and emphasise important features. Contrast refers to the visual difference in colour or tone between objects.

Usability – Solutions and graphic representation should be easy to use. The user should be able to acquire the required information with ease and efficiency.

Accessibility – A user should easily be able to gain meaningful and relevant information. A user should not have difficulty in understanding what is presented.

Design tools 33 What is the purpose of using a design tool?

To represent the functionality and appearance of solutions.

34 Describe a layout diagram. A layout diagram provides a visual depiction of how the final graphic representation should look.

Validating data 35 How is efficiency measured?

In terms of time, cost and effort.

36 How is effectiveness measured? A solution is considered effective if it is complete, reliable, attractive, clear, accurate, accessible, timely, relevant, and it communicates the message.


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37 List three spreadsheet software functions that enable a user to efficiently and effectively manipulate data. Lookup functions

Macros

Templates

38 Why is it important to use validation in a spreadsheet solution? To ensure the soundness of the input data – that it is appropriate and reasonable.

39 What types of errors would range checking, existence checking and data-type checking pick up? Range checking – that data falls within a certain range, such as postcodes within a state.

Existence checking – that data is present, such as that data that needs to be calculated is input.

Data-type checking – that data is of the correct type, such as that a phone number is text.

40 How can restricted data entry enhance the reliability of information in a spreadsheet? Restricted data entry provides the user with a limited choice of options that have already been validated and so this minimises the input of unreasonable data.

Formats and conventions 41 What is the difference between a format and a convention?

A format is a way of presenting data, such as centering text or adding dollar signs to represent currency.

A convention is an accepted and standard way of formatting data.

42 List five conventions that are used in spreadsheet design. Any of:

Text

• Use one space after all punctuation.

• Ensure the capitalisation of headings and names is consistent.

• Maintain consistency with margin widths, page numbering, column spacing and indentation.

• Ensure minimal use of different font sizes.

• Dates need to be consistently set out; for example, 27 April 2001. (Note there is no punctuation; date/month/year in full.)

• Use a serif font (has small strokes at the end of the character) for paragraph text.


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• Use a sans-serif font (no small strokes at the end of the character) for headings, tables and diagrams.

Numerical information

• Money values usually have two decimal places or none.

• Numbers are right-aligned in columns.

• Align decimal points (within a column and in totals).

• Position labels next to single numbers, such as $5.

• Position labels for columns of numbers at the top of the column.

• Percentages in columns appear at the top of the columns.

43 List five conventions that are used in graphic representations. Any of:

• Graphs and charts have titles.

• Use titles to identify the purpose of the graphic representation.

• x-axis and y-axis must be labelled.

• Use a key if more than one set of data is provided on the same graph or chart.

• Include author identification and/or source of data, date and a file name (if appropriate).

• Include unit of measurement on relevant axis.

• Label all segments in a pie chart.

• Arrange pie chart segments from largest to smallest.

• Choose colours that match the information being presented.

44 Identify the conventions that have and have not been applied in the graphic representation in Figure 1-34. • no chart title

• legend is incorrect

• no axis labels

• data labels are squashed

• font is inconsistent

• x-axis font is hard to read

Testing techniques 45 What are the characteristics of an effective solution?

A solution is considered effective if it is complete, reliable, attractive, clear, accurate, accessible, timely, relevant, and it communicates the message.


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46 What is the difference between validation and testing? Testing is performed to ensure that processes, functions and formulas in a solution work as expected. Validation checks that input data is appropriate and reasonable.

47 Which effectiveness measure has not been considered in each of the following? a A pie chart whose segments do not have data labels

Completeness

b A scatter diagram created from data that was found on a person’s social-networking site

Reliability

c A column chart with red and green columns

Accessibility

d A bubble diagram representing current Internet subscribers from 1998

Timeliness

Documents

Nelson Information Technology VCE Units 1 & 2 · PDF file© Cengage Learning Australia 2011 1 Nelson Information Technology VCE Units 1 & 2 Test your knowledge answers . Chapter 1: