CHAPTER 2 Information processing (Units 3 and 4)

Transcription

1 CHAPTER 2 Information processing (Units 3 and 4) Information-processing steps (page 54) a For each of the following information-processing steps, state its purpose and provide two examples of technology used to allow the step to be performed. Information-processing step Purpose Technology used Acquisition Input Validation Manipulation* Storage Output* Communication Retrieval Disposal b For two different software tools that you have used, describe two functions that can be performed to complete the steps that have an asterisk (*) in the table above.

2 Accessibility guidelines Testing validity of data Rules to test the validity of data include: reasonableness checks for example, data entered in the format 12/06/05 (dd/mm/yy) can be checked to ensure that the first two digits are in the range 1 31, the second two digits are in the range 1 12, and the year is not greater than 05 format consistency checks checking the order or format in which data is entered; for example, a password entered in lower case may be invalid if a case-sensitive rule requires the password to be entered in all-capitals limit checks these check that a value entered is not above or below a certain value existence checks these check that data has been entered in a particular field or text box, such as a website input form data consistency checks these check that data entered matches the data in a database, and is therefore valid default values these are set for commonly occurring data and are often used on website forms data type checks data of a particular type can be checked; for example, fields in a database can be set for alphabetical so that a name field will reject a numeric value drop-down list boxes these are often used on website forms and give users a list of options to choose from, enabling data to be entered quickly and accurately text checks spelling and grammar checkers in word processing tools can be used to check text

3 manual checks for example, proofreading for spelling and grammatical errors, reading back information, testing data such as survey questions, and printing drafts and checking them. Producing information: formats and conventions [2.14] What you need to consider when producing an information product.

4 Conventions checklists (page 33) Print output The following list of conventions is intended as a guide, rather than as a strict set of rules, to presenting print output effectively. Print output conventions change over time and checklists such as this one need to be updated periodically. Text Insert one space after a full stop and all other punctuation marks Do not insert a space before a punctuation mark such as? : ( ) / Use bold or italics for emphasis rather than underlining Use numbers for sequenced points in a list, such as instructions Use bullets for nonsequenced points in a list Use a clear hierarchy of headings and consistent heading styles Use a serif font (typeface) for paragraph text Use 9 12 point for the main text font Use 6 8 point text for captions and footnotes Use a sans-serif font for headings, tables and diagram labels As a general rule, set leading at 20 per cent above text size 10-point Helvetica is thus set on 12-point leading Restrict the number of fonts, type styles and font sizes used Use a maximum text line length of cm Limit sentence length to words Limit paragraph length to 3 5 sentences Avoid centred headings for long blocks of text Only centre short units of text (usually left justify) Use uppercase and lowercase consistently Use empty space to provide a rest space for readers Indent paragraphs or insert a line space before paragraphs Follow the Australia Post-preferred format for envelopes/mailing labels Follow established rules for referencing data Fully indent block quotations by 5 8 mm from the left margin and use a smaller font size than for paragraph text. Use margin widths, fonts, font sizes, paragraph indenting and column spacing consistently Use lists to break up the text and to assist readability Acknowledge data that is not original Numeric information Use a clear date format that requires minimal punctuation: dd DD MM YYYY for example: Sunday, 7 December 2003 Right-align numbers in columns Ensure that money values have either two decimal places or none Align decimal points Use a sans-serif font in a smaller size than for paragraph text Use a space to separate columns of numbers over 999; for example: In paragraphs, use a space or comma to separate numbers over 9999: for example: 1000 not not 15000

5 Label single numbers or columns of numbers with the appropriate symbol, for example $ and %, which should be shown at the top of columns in a table or next to single numbers Use a single line above subtotals in columns of numbers Use a single line above and a single or double line below grand totals in columns of numbers, with the total figure shown in bold Use graphics, symbols, lines, borders and shading consistently Graphs and numeric charts Choose the most appropriate graph or chart for your output, for example pie charts are used to compare pieces in a whole, bar charts are used to highlight differences between values, and line graphs are used to show trends or changes in values over time Provide a title for a graph or chart Label the x-axis and the y-axis on a bar chart or a graph On graphs show a scale on each axis and show the unit of measurement On bar charts show a scale on the vertical axis and show the unit of measurement Include a key or legend if more than one set of data is plotted on the same graph or chart Have each bar in a bar chart start at zero, where appropriate Clearly indicate individual bar values by providing a suitable scale or by labelling the end of each bar Label each segment in a pie chart Arrange the segments of a pie chart from largest to smallest, starting at the 12 o clock position Show absolute amounts as well as percentages on pie charts Indicate the source of the data on graphs and charts Colours Use colours consistently Use complementary colours Use colours that suit the content Avoid using red and green together (difficult to distinguish for colourblind people) Page layout Use a heading hierarchy Set most text in black Use one, two or three columns Use consistent page design elements throughout a document Use images that complement the content Number the pages of multipage documents Use common design elements throughout a document Use appropriate navigation systems, such as a table of contents, page numbering, an index and cross-references Use consistent margins Use contrast, colour and illustrations to enhance the page design Position captions below photographs and diagrams Acknowledge data that is not original

6 Web pages This list of conventions is intended as a guide to effective web page design, rather than as a strict set of rules. The application of these conventions will depend on the equipment used by the designer and by users. Also, web page design conventions are continually evolving and checklists such as this one need to be updated periodically. Text Add one space after a full stop and all other punctuation marks Do not insert a space before a punctuation mark such as? : ( ) / Use numbers for sequenced points in a list, such as instructions Use bullets for non-sequenced points in a list Use a clear hierarchy of headings Use consistent heading styles Avoid centred headings for long blocks of text Use uppercase and lowercase consistently Avoid using all-capitals Avoid using underlining Use bold and italics sparingly Indent paragraphs or insert a line space before paragraphs Follow established rules for referencing data Use only one or two fonts Avoid using drop-shadows on text Only centre short units of text (usually left justify) Use a sans-serif font for main text to ensure readability Use consistent fonts and font sizes (usually 9 12 pt) use no less than 12 pt for paragraph text Use a larger main text point size than for print documents Use fonts that are common across different platforms Limit sentence length to words Limit line length to a maximum of 60 characters (10 11 words) Limit paragraph size (4 8 lines) Animated text should move fairly slowly, and from right to left Numeric information Right-align numbers in columns Ensure that money values have either two decimal places or none Align decimal points Use a space to separate columns of numbers over 999; for example: In paragraphs, use a space or comma to separate numbers over 9999: 1000 not 1 000, not Label single numbers or columns of numbers with the appropriate symbol, for example $ and %, which should be shown at the top of columns in a table or next to single numbers Use a single line above subtotals in columns of numbers Use a single line above and a single or double line below grand totals in columns of numbers, with the total figure shown in bold If cells are used for tables, use bold or shading to distinguish totals Use graphics, symbols, lines, borders and shading consistently

7 Graphs and numeric charts There are many conventions for different types of graphs and numeric charts. For further details, refer to more detailed textbooks or information sources. Eg, the Macmillan title, (Macmillan, 2002). Sound Ensure that sound is clear Ensure that sound is not too long Indicate length of sound track, file type and size, such as WAVE (type), 645 KB (size), 1 minute (length) For hearing-impaired people, also include a transcript Still/moving images Keep videos short or images small to reduce transfer time Limit the size of all graphics files on a page to 100 KB Scan images at 72 dots per inch (dpi) Use appropriate file formats: JPEG for photos, GIF for other images (diagrams, navigation elements, animations, graphics containing text) Describe the video and file size and type, for example AVI (.avi), MPEG (.mpg;.mpe), QuickTime (.qt;.mov) Use small, coloured graphics as organisational and navigation buttons Limit animations to one per page Colours Avoid red text on a blue background Set most text in black Let main background in white or grey Avoid using red and green together (difficult to distinguish for colourblind people) Use colour consistently Limit the use of empty space, as it interferes with efficient scanning Use links as a source of colour Limit the number of colours used in text and figures to four Page layout Design for a 600 X 800 pixel screen Create one main frame Use single text columns Include a site title, a logo (if relevant) and the name of the site owner At the end of each page include a contact person s name and address, and the date of last modification Limit the use of hyperlinks Each page should contain a different concept or idea, and should be relevant and meaningful Display the most important information first Restrict the use of frames Each segment should fill a single screen if not enough text, combine with another Choose image files that complement the content Use the ALT attribute in image tags Provide text links with linked images, including image maps Provide descriptive captions with photographs Use consistent design elements throughout the site Use consistent, clear and concise navigation elements, and position them in the same place on every page Choose predictable icons, such as a question mark for a help sign Placement of the navigation bar depends on the length of the page at top usually; on longer pages place navigation links also at bottom

8 Links to external pages should be meaningful, and should be acknowledged with a prompt saying that the user is leaving the website and entering another site Use lists where possible Home page/core page should not take more than seconds to load Include a search function if large amounts of information are provided Important information should never need more than three hops/clicks to access Users should need no more than four or five hops/clicks to get to 80 per cent of the documents they want to view Acknowledge data that is not original Text charts A text chart is a diagrammatic representation of one or more concepts. The purpose of a text chart is to convey complex information in a clear and concise way, and to highlight relationships between the concepts presented. A well-designed text chart should: have a title that identifies the concepts presented contain clear, complete and explicit information have a descriptive title or caption use connecting lines and arrows to show the relationships between the concepts use a consistent style for the text, boxes, lines and arrows use a sans-serif font. [2.15] A consistent style for text, boxes, lines and arrows is used.

9 Tables [2.16] Text table. [2.17] Numeric table.

10 [2.18] Another numeric table. Numeric charts and graphs [2.19] Stacked-bar chart.

11 [2.20] Multiple bar chart. [2.21] Line graph. [2.22] Pie chart that follows proper conventions.

12 Financial reports Statement of financial performance (This used to be known as the profit and loss statement.) [2.23] Statement of financial performance.

13 Brochures [2.24] Sample brochures.

14 Newsletters [2.25] A newsletter.

15 Databases Screen format [2.26] Database screen format.

16 Report format [2.27] Database report format.

17 Spreadsheets [2.28] A spreadsheet.

18 Webpages [2.29] The Australian Red Cross website, <