Behavior Research Methods, Instruments, & Computers 1986, 18 (2), 129-134 SESSION III SOFTWARE APPLICATIONS Paper Session Stephen Link, Presider Remembering computer command names: Effects of subject generation versus experimenter imposition MARC M. SEBRECHTS, CHARLOTTE T, FURSTENBERG, and ROXANNE M. SHELTON Wesleyan University, Middletown, Connecticut Two experiments analyzed the effectiveness of goal statements in aiding recall ofself-generated as opposed to experimenter-imposed command names. Subjects were presented with a series of before-after pairs representing the computer states before and after a command was executed. In Experiment 1, during study, one group of subjects generated a command name in response to each pair; a second group generated a goal statement describing the goal to be accomplished in addition to generating a command name. During recall, half of each group was required to recall the name, whereas the other half was required to describe the goal before attempting to recall the name. In Experiment 2, during study, command names (and goals for those subjects in the goal condition) were imposed by the experimenter rather than generated by the subject. Subjects who generated goals and names recalled more command names than did those who gener- ated only names or who received imposed goals and/or names. Generation of an appropriate goal at study improved encoding by helping subjects to select more appropriate command names; gener- ation of an appropriate goal at test improved retrieval for appropriate names only, presumably by activating a relevant subset ofnames. Even in the relatively simple task of naming and remem- bering command names, having an appropriate model of the domain through the use of specific goal statements substantially improved performance. Using computers requires a precise way to specify the tasks that the computer is to perform: this constitutes what is called the command language problem. There are, of course, many alternative ways to implement a command language, including specific command terms, a natural language interface, icons, and menu selection. This paper focuses on the use of specific command names, a common practice in most current computer sys- tems. The main concerns here are: (1) does self- generation provide a usable set of command names, and (2) what characteristics are important for optimal com- mand generation and recall. Previous studies have suggested a number of problems with having novice subjects generate command names (see Black & Sebrechts, 1981). In a study by Landauer, Galotti, and Hartwell (1983), subjects were asked to pro- This research was supported by NSF Grant IST82-l7572 and by a research grant from Digital Equipment Corporation. The views expressed are those of the author and are not necessarily endorsed by Digital Equip- ment Corporation. Send correspondence to: M. M. Sebrechts, Depart- ment of Psychology, Wesleyan University, Middletown, CT 06457. vide a procedure for a series of editing changes. There was no substantial agreement across subjects on basic names for operations. Furthermore, many subjects did not even use the same verb for two different instances of the same type of correction. In a second study, Landauer et al. (1983) compared the learning of a simplified text editor using one of three types of command names: the modal ("natural") responses from the previous generation study, standard UNIX ED commands, and random names. They found no reliable differences in time to complete a basic set of tasks based on the type of command name, suggesting that the natural naming does not produce more memorable names. In a related study, Black and Moran (1982) had a group of subjects generate single-sentence descriptions of the difference between two before-after text fragments, representing eight editing operations. They then compared performance of another group who learned the frequently produced names from the generation study with a group that learned designer-generated names. They found no retention differences beween the subject-generated and designer-generated names. 129 Copyright 1986 Psychonomic Society, Inc.