ANSWERS TO CHAPTER EXERCISES (CHAPTER 8)
Review Questions
1. List and describe various types of output, including technology-based forms of information delivery.
Technology advances have had an enormous impact on how people communicate and obtain information. In addition to printed output, other forms of output include:
· Internet-based information delivery: Millions of firms use the Internet to reach new customers and markets around the world.
· E-mail: E-mail has become an essential means of internal and external business communication. Employees send and receive e-mail on local or wide area networks, including the Internet.
· Audio output: Audio output can be attached to an e-mail message or inserted as an audio clip in a document. In addition, many firms use automated systems to handle voice transactions and provide information to customers.
· Automated facsimile systems: Some firms use automated facsimile, sometimes called faxback systems, to allow a customer to request a fax using e-mail, the company Web site, or by telephone. The response is transmitted in a matter of seconds back to the user’s fax machine.
· Computer output to microfilm (COM): COM systems, such as microfilm and microfiche, capture an image of a document and produce film output. Users then can retrieve, view, and print the images.
· Computer output to laser disk (COLD): Computer output to laser disk (COLD) is a relatively new way to store images of paper documents. Using COLD technology, a paper document is scanned, and the digital image is stored on a high-density laser disk medium. COLD technology also enables rapid information retrieval of formatted information. For example, if an insurance company stores thousands of paper application forms, special software can treat the document as data and extract information from a particular column or area on the form.
- Specialized forms of output: Businesses require a variety of specialized output devices, such as retail point-of-sale terminals, automated teller machines (ATMs), special-purpose printers, plotters, digital camera, and programmable devices (such as television sets, VCRs, and microwave ovens) that produce visual output displays. (Pages 334-337)
3. Explain the concept of human-computer interaction (HCI).
Human-computer interaction describes the relationship between computers and people who use them to perform business-related tasks. HCI concepts apply to everything from a PC desktop to the main menu for a global network. HCI includes all the communications and instructions necessary to enter input to the system and to obtain output in the form of screen displays or printed reports. (Page 348)
4. Describe eight principles for a user-centered interface design.
Eight principles for a user-centered design are:
§ Understand the underlying business functions
§ Maximize graphical effectiveness
§ Profile the system’s users
§ Think like a user
§ Use prototyping
§ Design a comprehensive interface
§ Continue the feedback process
§ Document the interface design (Page 351-352)
5. Explain each of the data validation checks mentioned in this chapter.
Data validation checks include the following:
§ Sequence checks are used when the data must be in some predetermined sequence.
§ Existence checks are used for mandatory data items.
§ Data type checks test to ensure that a data item fits the required data type.
§ Range checks test data items to verify that they fall between a specified minimum and maximum value.
§ Reasonableness checks identify values that are questionable, but not necessarily wrong.
§ Validity checks are used for data items that must have certain values.
§ Combination checks are performed on two or more fields to ensure that they are consistent or reasonable when considered together.
§ Batch controls are totals used to verify batch input and might involve checking data items such as record counts and numeric field totals. (Pages 365-366)
6. Describe six types of user interface controls, and provide an example of how you could use each type in a data entry screen.
Controls can include menu bars, toolbars, dialog boxes, text boxes, toggle buttons, list boxes, scroll bars, drop-down list boxes, option buttons, check boxes, command buttons, and calendar controls, among others. Controls can be used as follows:
§ Menu bar: The main menu options display at the top of the screen in a menu bar. Some software packages allow you to create customized menu bars and toolbars.
§ Toolbar: A toolbar contains icons or buttons that represent shortcuts for executing common commands. The commands might be navigation shortcuts or can trigger other actions.
§ Command button: Command buttons initiate an action such as printing a form or requesting Help.
§ Dialog box: A dialog box allows a user to enter information about a task that the system will perform.
§ Text box: A text box can display messages or provide a place for a user to enter data.
§ Toggle button: A toggle button is used to represent on or off status — clicking the toggle button switches to the other status.
§ List box: A list box displays a list of choices that the user can select.
§ Scroll bar: A scroll bar allows the user to move through the available choices when they do not all fit on the screen.
§ Drop-down list box: A drop-down list box displays the current selection. When the user clicks the arrow, a list of the available choices displays.
§ Option button: Option buttons, or radio buttons, represent groups of options. The user can select only one option at a time; selected options contain a black dot.
§ Check box: A check box is used to select one or more choices from a group. A checkmark or an X represents selected options.
§ Calendar control: A calendar control allows the user to select a date that the system will display and store as a field value. (Pages 358-359)
7. Explain the concept of a GUI and a switchboard. How does a GUI design differ from a character-based screen design?
A GUI uses graphical objects and techniques. A well-designed GUI helps users learn and use a system effectively. Now that GUIs have become universal in application packages, users expect in-house software also to have GUIs. Unlike a character-based screen design, a GUI combines process control and data entry. A switchboard is an opening screen that introduces an application and allows users to view the main options. A switchboard contains command buttons that enable users to navigate the system and select tasks. (Pages 348, 351, 359)
8. Explain batch and online input methods. Define source data automation and provide an example.
Using batch input, data entry is performed on a specified time schedule, such as daily, weekly, monthly, or longer. Although batch input is used in specific situations, most business activity requires online input. Online input offers immediate validation and availability of data.
A popular online input method is source data automation, which combines online data entry and automated data capture using input devices such as magnetic data strips, or swipe scanners. Examples of source data automation include retail stores that use portable bar code scanners to log new shipments and update inventory data, and libraries that use handheld scanners to read optical strips on books. (Page 360, 362)
10. Provide four guidelines for reducing input volume.
Four guidelines for reducing input volume are:
§ Input necessary data only. Do not input a data item unless it is needed by the system.
§ Do not input data that the user can retrieve from system files or calculate from other data.
§ Do not input constant data. If orders are in batches with the same date, then a user should enter the order date only once for the first order in the batch. If orders are entered online, then the user can retrieve the order date automatically using the current system date.
§ Use codes whenever possible. Codes are shorter than the data they represent, and coded input can reduce data entry time. (Pages 362-363)
