Psychological Research on Videotex

Behavior Research Methods & Instrumentation 1982. Vol. 14 (2),19/-/97 SESSION X WHERE THE WORLD IS HEADING Psychological research on videotex RICHARD F. DILLON and JO W. TOMBAUGH Carleton University, Ottawa KIS 5B6, Canada Videotex is considered to be a powerful, but simple to use, computer network available for use in homes, offices, and schools. Information in the form of text and color graphics can be requested and displayed on the user's television set. While retrieval of information is the first service provided on videotex, many other services, including electronic mail, electronic shopping, and electronic funds transfer, will be developed. However, in order to achieve the popularity predicted for videotex, a number of human factors and social problems must be solved. Research concerning some of these problems, and the role psychologists can play in their solution, is described. Videotex is sometimes referred to, somewhat inaccu systems, they all share similar functions and have similar rately, as two-way television. It makes available the plans for the future. In particular, they all currently power of large mainframe computers to untrained users emphasize information retrieval services for users, with in their own homes, offices, or schools. The user can the central computer used primarily as a massive communicate with the central videotex computer over information storage device. In current implementations the telephone lines, using his own color television set (e.g., Bown, O'Brien, Sawchuk, & Storey, Note 1), the as a display device and a small special-purpose keypad or central computer basically monitors requests for infor standard keyboard as an input device. The videotex mation from many users at one time, finds the requested terminal, which is an inexpensive bu t powerful micro information on rapid-access mass disk storage, and sends processor, serves as the interface between the user and the information over the telephone lines to the person the central videotex computer. Hundreds of computer who requested it. Such videotex systems are sometimes naive users can be accessing a central computer at one confused with a similar system called teletex, which time. Because of the projected low cost and ease of use, "broadcasts" information repeatedly on unused parts it is possible that videotex terminals will become as of the television signal. In the noninteractive teletex commonplace as the telephone and television. In France system, a user's request for information "sets" the alone, where the French government plans to provide terminal to receive that information when it is next the telephone directory on a videotex system, there will broadcast a short time later. Thus, there is no communi be videotex terminals in 30 million homes by 1992 cation from user to central computer, as there is on (Bright, 1981). This paper describes what videotex is, videotex. This paper focuses on videotex and its inter and how psychologists can contribute to the develop active capability, although some of the problems dis ment of such an important and far-reaching technology. cussed are common to both videotex and teletex. Storage of information in all current systems is AN INTRODUCTION TO VIDEOTEX organized in a hierarchy or logical tree branching out from a small number of general information categories Information Retrieval on Videotex Systems at the root node to more and more specific information A number of different videotex systems are under as the branches spread out. In order to make the system development (e.g., Woolfe, 1980). For example, the easy to use and to free the computer for monitoring French government has developed a system known as requests from many users, a menu selection technique Antiope, the British Post Office has developed Prestel, has typically been implemented. Figure 1 shows a and the Canadian Department of Communications, typical menu page as it would appear on the television in collaboration with Bell Canada, has designed Telidon. screen. The user selects a topic by entering numbers Although there are important differences among these on the keypad that correspond to the menu item chosen. From the general choices shown in this display, suc This research was supported by Grant G0365 from the cessively more detailed choices can be made. Figure 2 National Science and Engineering Research Council of Canada shows how a user works through one branch of the to the authors. tree to find baseball scores. The final page that actually Copyright 1982 Psychonomic Society, Inc. 191 0005-7878/82/020191-07$00.95/0 192 DILLON AND TOMBAUGH that will appear on videotex. It is expected that users TABLE OF CONTENTS will be able to subscribe to a number of different data bases, having different cost arrangements, including free service (e.g., for department store advertisements), 1. NEWS, WEATHER, & SPORTS 2. BUSINESS & FINANCE INFORMATION a fee based on number of pages accessed, or a monthly 3. GOVERNMENT INFORMATION & SERVICES subscription fee. Some data bases will be for specialized q. SALES, RENTALS, & SERVICES s , ENTERTAINMENT clientele (e.g., a stock market data base, agricultural 6. TRAVEL . data base, airline schedules, etc .), and others will be 7. JOBS, CAREERS, & OPPORTUNITIES 8. EDUCA lION more general in nature (a combination newspaper, 9. INTERNATIONAL INFORMATION encyclopedia, yellow pages, and consumer catalog). Ultimately, the information that appears in the data base will depend on what people want and are willing to pay for. PRESS NUMBER OF CHOICE, THEN PRESS SEND Videotex Graphics One of the major features of videotex systems is that Figure 1. A typical videotex menu page. data-base information can be stored in text form and in color graphic form. At present, these capabilities are limited by the technology available. One of the major User sees: TAE:LE OF CONTENTS limitations is the resolution of current home color 1. News television sets. Text is displayed with a maximum of 20 2, Weather 3, Sports lines, with up to 40 characters per line. This tex t resolu q, ... 5 • ... tion is less than one-half the capability found on most noncolor CRT terminals. Graphic resolution is also User selects 13 and sees: SPORTS limited. Maximum graphic resolution possible on a I. Hockeq standard color television set is approximately 256 by 256 2, aaseoar t 3. Football pixels. q. ." Three modes of storing and transmitting graphic "' , .. information have been developed: bit-mapped graphics, User selects 12 and sees: E:ASEE:Al.L alphamosaic, and alphageometric representations (e.g., 1. Bc-or-ss Milton, 1981). In the bit-mapped graphics mode, the 2. F'u t.ur-e gaMeS 3, TeaM starldin9s central videotex computer stores color and brightness q, Statistics information arranged in an m by n matrix (e.g., 256 User selects 11 and sees: E:ASEE:Al.L SCORES rows by 256 columns). This information is sent, one New Yo!"!': 6 St.LOU1S q point at a time, to the terminal. Pictures drawn using ct-c c e s c :l Pittsburg 1 this technique are slow to display, often taking minutes rtcrrt.rea I q Phi ladelphia 3 to complete, and they are expensive and difficult for the information provider to draw. In the alphamosaic tech nique, the complete picture is stored in a 40 by 20 Figure 2. Menus shown while selections are made by a user array in the central computer and is transferred to the interested in finding information about baseball scores. terminal on request. Thus, pictures are formed by using graphic characters of the sort found on inexpensive personal computers (e.g., on the Commodore PET home contains the information, in this case the baseball scores, computer). This technique has the advantage that it is called a document. Documents can be one page or allows use of inexpensive graphics terminals with fast many pages in length, and there are thousands of these transmission speeds, but it has two limitations. First, pages available in the videotex tree. resolution is poor relative to the other two modes, and, It is important to realize that the computer does second, the poor resolution is built into the stored repre not generate information. It simply retrieves information sentation of the picture. To appreciate this limitation, that has previously been stored in the data base by per the alphageometric approach must be understood. The sons known by the Orwellian title of "information alphageometric approach does not store pictures on the providers." Advertisements, entertainment, and infor central computer but stores picture description instruc mation for videotex is being produced under the same tions (known as POls) instead. Picture descriptors types of commercial arrangements followed in providing provide information such as the starting point, diameter, television content. As a result, at the present time, most color, and brightness of a circle. This coded information systems are in an experimental stage and data bases are is stored on the central computer and sent to the termi not well developed. A major question is whether inde nal that interprets and displays the information. The pendent information providers in North America will, terminal itself is a microprocessor with software to indeed, improve the quantity and quality of documents generate graphics, and the circle that is drawn using PSYCHOLOGICAL RESEARCH ON VIDEOTEX 193 alphageometrics is determined by the capability of the (Harker, 1981). In the videotex future, transfer of terminal and display. With high-resolution systems, a money will be simplified to transfer of information high-resolution circle will be drawn, and with low about money. resolution systems, a low-resolution circle will be drawn, The combination of a large central computer and a but both will come from the same picture descriptors small but smart terminal can be used for many other ser stored on the central videotex computer.

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