16.5 “Discuss the advantages of the graphical information display and suggest four applications where it would be more appropriate to use graphical rather than digital displays of numeric information.”
Ans. “A constantly changing digital display can be confusing and irritating as readers can’t read and assimilate the information before it changes. Such dynamically varying numeric information is therefore best presented graphically using an analogue representation”.
Graphical presentation of sales information of different months “as a histogram, makes the anomalous figures. Managers studying sales figures are usually more interested in trends or anomalous figures rather than precise values”.
“Graphical display of temperature will show the maximum and minimum values. With only a digital value, the viewer must know the maximum values and mentally compute the relative state of the reading”. The extra thinking time can be reduced by using graphical display.
Four applications :
1. “Weather information, gathered from a number of sources, is shown as a weather map with isobars, weather fronts, and so on .”
2. Summaries the sales information of a company on a monthly basis can us graphical rather than digital display.
3. Representing share values in a period of time in graphical display would be more appropriate than numeric display.
4. Displaying the sale price of producd(s), in stores, supermarkets.
16.6 “What are the guidelines that should be followed when usinf colour in auser interface?”
Ans. 1. “Limit the number of colours employed and be conservative how these are used. You should not use more than four or five separate colours in a window and now more than seven in a system interface”.
2. “Use colour change to show a change in system status. If a display changes a colour this should mean a significant event has occurred”.
3. “Use colour coding to support the task user are trying to perform. If they have to identify anomalous instances, highlight these instances; if similarities are also to be discovered, highlight these using a different colour”.
4. “Use colour coding in a thoughtful and consistent way”.
5. “Be careful about pairings. Because of the physiology of the eye, people cannot focus on red and blue simultaneously”.