Answers to End-of-Chapter 8 - Text Exercises

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Answers to End-of-Chapter 8 - Text Exercises

  1. 1. Answers to End-of-Chapter 8 - Text Exercises Self-Test Questions 1. [small to large] bits, bytes (characters), fields, records, files 2. field 3. database administrator (DBA) 4. privacy 5.hierarchical; network; relational; object-oriented; multidimensional 6. program files; data files 7. compression 8. byte 9. database 10. record 11. robot 12. natural language processing 13. AI (artificial intelligence) 14. simulators 15. identity theft 16. research & development; production (operations); marketing & sales; accounting & finance; human resources; information system 17. SQL (structured query language) Multiple-Choice Questions 1. c 2. c 3. b 4. e 5. d 6. c 7. c True/False Questions 1. T 2. F 3. T 4. F 5. T 6. F 7. T 8. F 9. F 10. F 11. F 12. F Short-Answer Questions Short-Answer Questions 1. The database administrator (DBA) is the person who coordinates all related activities and needs for an organization’s database. The DBA determines user access privileges; sets standards, guidelines, and control procedures; assists in establishing priorities for requests; prioritizes conflicting user needs; and develops user documentation and input procedures. He or she is also concerned with security—setting up and monitoring a system for preventing unauthorized access and making sure that the system is regularly backed up and that data can be recovered should a failure or disaster occur. 2. Data mining (DM) refers to the computer-assisted process of sifting through and analyzing vast amounts of data in order to extract meaning and discover new knowledge. The purpose of DM is to describe past trends and predict future trends. Thus, data-mining tools might sift through a company’s immense collections of customer, marketing, production, and financial data and identify what's worth noting and what's not.
  2. 2. 3. A data warehouse is a database containing cleaned-up data and meta-data (information about the data). The data is stored using high-capacity disk storage. Data warehouses combine vast amounts of data from many sources in a database form that can be searched, for example, for patterns not recognizable with smaller amounts of data. 4. Four advantages of databases: (1) reduced data redundancy; (2) improved data integrity; (3) increased security; ease of data maintenance. 5. Data files are files that contain data—words, numbers, pictures, sounds, and so on. These are the files used in databases. Unlike program files, data files don’t instruct the computer to do anything. Rather, data files are there to be acted on by program files. Examples of common extensions in data files are .txt (text) and .xls (Excel worksheets). Certain proprietary software programs apply their own extensions, such as .ppt for PowerPoint and .mdb for Access. Program files are files containing software instructions. Examples are word processing or spreadsheet programs, which are made up of several different program files. The two most important are source program files and executable files. Source program files contain high-level computer instructions in the original form written by the programmer. Some source program files have the extension of the language in which they are written, such as .bas for BASIC, .pas for Pascal, or .jav for Java. (Appendix A has information about programming languages.) For the processor to use source program instructions, they must be translated into an executable file, which contains the instructions that tell the computer how to perform a particular task. You can identify an executable file by its extension, .exe. You use an executable file by running it— as when you select Microsoft Excel from your on-screen menu and run it. (There are some executable files that you cannot run—other computer programs called runtime libraries cause them to execute. These are identified by such extensions as .dll, .drv, ocx, .sys, and .vbx.) 6. An expert system, or knowledge-based system, is a set of interactive computer programs that helps users solve problems that would otherwise require the assistance of a human expert. Expert systems are created on the basis of knowledge collected on specific topics from human specialists, and they imitate the reasoning process of a human being. Expert systems have
  3. 3. emerged from the field of artificial intelligence, the branch of computer science that is devoted to the creation of computer systems that simulate human reasoning and sensation. Expert systems are used by both management and nonmanagement personnel to solve specific problems, such as how to reduce production costs, improve workers’ productivity, or reduce environmental impact. Because of their giant appetite for memory, expert systems are usually run on large computers, although some microcomputer expert systems also exist. For example, Negotiator Pro for IBM and Macintosh computers helps executives plan effective negotiations by examining the personality types of the other parties and recommending negotiating strategies. 7. SQL = structured query language, the standard language used to create, modify, mainstream, and query relational databases. Access is a relational database model for microcomputers; Oracle and DB2 are relational database models used on larger computer systems. 8. E-commerce refers to the buying and selling of products and services through computer networks. E-commerce and online shopping are growing very quickly around the world. 9. On a regular basis—once a year, say—get a copy of your credit report from one or all three of the main credit bureaus. This will show you whether there is any unauthorized activity. Check your credit-card billing statements: If you see some fraudulent charges, report them immediately. If you don’t receive your statement, call the creditor first. Then call the post office to see if a change of address has been filed under your name. Treat credit cards and other important papers with respect: Make a list of your credit cards and other important documents and a list of numbers to call if you need to report them lost. (You can photocopy the cards front and back, but make sure the numbers are legible.) Carry only one or two credit cards at a time. Carry your Social Security card, passport, or birth certificate only when needed. Don’t dispose of credit-card receipts in a public place. Don’t give out your credit-card numbers or Social Security number over the phone, unless you have some sort of trusted relationship with the party on the other end. Tear up credit-card offers before you throw them away. Keep tax records and other financial documents in a safe place. Treat passwords with respect: Memorize passwords and PINs. Don’t use your birth date, mother’s maiden name, or similar common identifiers, which thieves may be able to guess.
  4. 4. Treat checks with respect: Pick up new checks at the bank. Shred canceled checks before throwing them away. Don’t let merchants write your credit-card number on the check. Watch out for “shoulder surfers” when using phones and ATMs: When using PINs and passwords at public telephones and automated teller machines, shield your hand so that anyone watching through binoculars or using a video camera—“shoulder surfers”—can’t read them. 10. Short life span of storage media: The storage media themselves have a short life expectancy, and often the degradation is not apparent until it’s too late. The maximum time seems to be 50 years, the longevity of a high-quality CD. Some average-quality CDs won’t last 5 years, according to tests run at the National Media Laboratory. The magnetic tapes holding government records, which are stored in the National Archives in Washington, D.C., need to be “refreshed”—copied onto more advanced tapes—every 10 years. Hardware and software obsolescence: Even when tapes and disks remain intact, the hardware and software needed to read them may no longer be available. Without the programs and computers used to encode data, digital information may no longer be readable. 11. An intelligent agent is a form of software with built-in intelligence that monitors work patterns, asks questions, and performs work tasks on a person’s behalf, such as roaming networks and compiling data. One type of intelligent agent is a kind of electronic assistant that will filter messages, scan news services, and perform similar secretarial chores. Microsoft Office has an agent called Office Assistant that can answer questions, offer tips, and provide help for a variety of features specific to the program being used. Also, shop bots (bots or network agents) search the internet and online databases for information and bring the results back to you. 12. Virtual reality (VR), a computer-generated artificial reality, projects a person into a sensation of three-dimensional space. To put yourself into virtual reality, you need software and special headgear; then you can add gloves, and later perhaps a special suit. The headgear—which is called a head-mounted display—has two small video display screens, for each eye, to create the sense of three-dimensionality. Headphones pipe in stereophonic sound or even 3-D sound; so that you think you are hearing sounds not only near each ear but also in various places all around you. The glove has sensors for collecting data about your hand movements. Once you are wearing this equipment, software gives you interactive sensory feelings similar to real-world experiences.
  5. 5. 13. Weak AI makes the claim that computers can be programmed to simulate human cognition— that some “thinking-like” features can be added to computers to make them more useful tools. Weak AI is used in expert systems, speech-recognition software, computer games, and the like. Strong AI makes the claim that computers can be made to think on a level that is at least equal to humans and possibly even be conscious of themselves. So far, most AI advances have been piecemeal and single-purpose, such as factory robots, but proponents of strong AI believe that it’s possible for computers to have the kind of wide-ranging, problem-solving ability that people have. Two different approaches are Cyc and Cog. 14. Main areas of AI are expert systems; natural language processing; intelligent agents; pattern recognition; fuzzy logic; virtual reality and simulation devices; robotics. 15. A decision support system (DSS) is a computer-based information system that provides a flexible tool for analysis and helps managers focus on the future. It gathers and presents data from a wide range of sources in a way that can be interpreted by humans. Some decision support systems come very close to acting as artificial intelligence agents. DSS applications are not single information resources, such as a database or a program that graphically represents sales figures, but a combination of integrated resources working together. Whereas a TPS records data and an MIS summarizes data, a DSS analyzes data. To reach the DSS level of sophistication in information technology, an organization must have established TPS and MIS systems first. Many DSSs are developed to support the types of decisions faced by managers in specific industries, such as airlines or real estate. Many companies use DSSs called geographic information systems (GISs), such as MapInfo and Atlas GIS, which integrate geographic databases with other business data and display maps. Also called an executive information system (EIS), an executive support system (ESS) is an easy-to-use DSS made especially for strategic managers; it specifically supports strategic decision making. It draws on data not only from systems internal to the organization but also from those outside, such as news services or market-research databases. An ESS might allow senior executives to call up predefined reports from their personal computers, whether desktops or laptops. They might, for instance, call up sales figures in many forms—by region, by week, by anticipated year, by projected increases. The ESS includes capabilities for analyzing data and doing “what-if” scenarios. ESSs also have the capability to browse through summarized
  6. 6. information on all aspects of the organization and then zero in on (“drill down” to) detailed areas the manager believes require attention. ESSs are relatively user-friendly and require little training to use. Responses to Knowledge in Action and Web exercises will vary throughout.

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