Citation: Stodolsky, D. (1987). Dialogue management program for the Apple II computer. Behavior Research Methods, Instruments, & Computers, 19, 483-484.
Many procedures for allocation of turns to speakers have been advocated for both face-to-face dialogue and teleconferencing (Stodolsky, 1978). Such procedures typically seek to promote a balance in participation through application of fair allocation rul es. They sometimes incorporate protected modes of expression, such as anonymous voting, into the dialogue management rules. In order to encourage concise statements and prompt treatment of a topic or motion,the rules often set limits on how long each per son can speak and on the total time for conferencing.

The DIALOG PSD NO CLK (DIALOGue management with Paddles, Sound, Data and NO CLocK) program for the Apple II Plus computer uses an equal-time resolution rule to allocate time to speakers, and limits turns and total time to values entered at the beginni ng of conferencing (Stodolsky, 1981a). The equal-time resolution rule resolves conflicting requests for a turn in favor of the person who has thus far had the least time.

One way to understand the operation of the system is to think of each speaker as having a computer, which in certain conflicts acts as a confidential agent. When many persons wish to talk at the same time, these agents negotiate to determine which per son will speak first. With this program, it is as if the agents compare their clocks which show how long each person has thus far spoken. The person permitted to speak has the least time on their clock, that is, the one who has thus far spoken the least.

The transition from speaker to speaker is protected in these cases, since the responsibility for either cutting off an over-time speaker or rejecting a pending request is shared by the group, as opposed to being the sole responsibility of the succeedi ng speaker, which is the case in unstructured dialogue (Stodolsky, 1981b). This is true for two reasons, first the group has agreed to use the program to select among conflicting requests. Second, at any contested transition, between one and all of the l isteners have requests pending, thus indicating a desire to terminate the turn of the current speaker. Neither the presence of, nor the source of a request is revealed if it is rejected. An accepted request is revealed only when the name of the new speak er appears. The protective mechanism is equivalent to that used by scientific journals which have blind review (author anonymity during the review process). That is, contributors name's are only revealed if they are selected to present their message.

Persons in groups which used the equal-time resolution rule showed superior task performance and experienced less frustration as compared to persons in groups using a first-in first-out resolution rule. Also, in groups using the equal-time resolution rule, persons who were fearful of speaking in groups were felt to be group leaders just as often as persons who were not fearful (Zimbardo, Linsenmeier, Kabat & Smith,1981). Teams working in the telecommunication settings made better decisions, enjoyed t hemselves more, experienced less frustration, and viewed their teams' decisions more favorably as compared to face-to-face groups (Linsenmeier & Zimbardo, 1982). These preliminary results are unusual when compared with other work on telephone meetings. S uch meetings typically result in greater dissatisfaction and inferior performance as compared to face-to-face interaction (Weston & Kristen, 1973; Weston, Kristen & O'Connor, 1975).

The program described here uses standard Apple II game paddles for input requests. Up to four participants can be accommodated if all paddle inputs of the game input/output port are used. Paddles function as binary inputs, the knob is turned completel y clockwise to request a speaking turn and completely counter clockwise to relinquish a turn or continue listening to the current speaker. As each new speaker is selected, the speaker's name is displayed and a number of beeps indicating the selected padd le is produced. This simple audio indication eliminates the need for the group to either look at the screen or have a person announce the name of the new speaker. Time remaining is updated at the start of each new turn. The total time for conferencing is also displayed.

After presenting instructions, the program requests the turn limit, the minimum time a person can speak without an interruption. There is no maximum time, since only another's request can interrupt the current speaker. Interruptions are permitted on e ach occasion that the turn limit is reached, but only by those who have used less time than the speaker. If no interruption occurs, then the current speaker can continue for at least the turn limit again. Finally, the program requests the total time limi t for the conference, and number of participants. Each participant's name is then requested. After the last name is entered, the program presents the message,"Waiting for new speaker," or the name of the speaker requesting a turn, and starts timing the s ession. When the total time for conferencing is exceeded, the program permits the current speaker's turn to expire and then halts conferencing. Finally, it displays approximate elapsed speaking time of each person.

Since no clock is used by the program, time keeping is based upon an input scanning and time limit checking loop. This procedure maintains an approximately correct interval scale relationship among the speaking times of different persons, but does not account correctly for waiting periods and thus overall time. A single parameter allows adjustment for different models of the Apple II. Approximate real-time accounting is achieved by altering the loops-to-seconds translation.

The program is written in Applesoft (R) BASIC. The part of the program that collects inputs is isolated in a subroutine. This facilitates increasing the number of speakers permitted, either by use of an operator who enters requests on the Apple II key board or by direct inputs from participants through individual keyboards or switches. The display procedures are also isolated, which facilitates utilization of an external display generation device. The program can be used directly as a demonstration of the equal-time resolution rule or incorporated into another system, such as one for multimedia computer-based conferencing, as a module for coordination of turn taking. A comprehensive set of FORTRAN modules used for experiments which included condition s using the equal-time resolution rule and the first-in first-out rule were presented earlier (Stodolsky, 1976). These assume data storage in the modules for collecting requests. Modules not requiring this deviation from FORTRAN standards are available f rom the author at cost.


The BASIC program listing is available without charge. DOS 3.3 copies of this and related programs, that permit operator input for up to 10 persons and use of an interface for direct input for up to 16 persons, are available. They are supplied with progr ams which permit use of a Mountain Hardware clock (Stodolsky,1984) and may be obtained by sending a blank diskette to the author.


David S. Stodolsky
Euromath Center
University of Copenhagen
Note As soon as it arrives via post from Denmark, I will be posting the PSD No CLK program to this Web site for downloading. If you need it on disk, you will also be able to order it from me.
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