The Effect of Three Types of Visual Irrelevancy on Complex Decision Making1

Abstract

The present study investigated the effects of visual information irrelevancy on complex decision. making. Three types of irrelevancy were defined (clutter, r1oninf'ormative irrelevancy and coding redundancy) and incorporated as independent variables in the research. Thirty male college §.S solved a set of static problems involving decision making with a known pay-off, but where the output would be difficult for .2 to accurately estimate. Results indicated that, under the conditions of this study, irrelevancy is facilitative for decision making and the more random the irrelevancy, the more adequate the solution. These findings ape discussed within the framework of a theory that postulates that irrelevancy aids in the figure-ground articulation of the cognitive field. THE EFFEGr OF THREE TYPES OF VISUAL IRRELEVANCY ON 1 COMPLEX DECISION MAKINGThe term irrelevant information in the psychological literature re~ers to two quite separate sets of experimental manipulations. On the one hand, it has been used to refer to an asynchrony between training and criterion trials in concept identification tasks. Thus, 2 is trained on one stimulus dimension and later tested in a concept identification situation wherein the training dimension cannot be used to attain correct categorization.The other usage of the term derives from the use of additional stimuli in search-time discrimination tasks. In this type of task, S has to identify critical stimuli in a "noisy" field. These studies have derived their impetus from the problems faced by a radar operator on extended watches.The results of almost all of the studies investigating the effects of irrelevancy as a training variable have suggested that the inclusion of such a variable at best does not affect performance. Thus, Archer (1954) fo~d that response time in a concept formation task increased as a linear function of the amount of relevant information, but was independent of the level of irrelevancy. Archer, Bourne, and Brown (1955) found that as irrelevant elements were increased, efficiency of categorizing unusual patterns decreased even when ,2swere instructed how to test for irrelevancy.Henneman (1957) and Morin, Forrin, and Archer (1961) verified Archer's (1954) study that irrelevancy does not significantly degrade performance. In addition, Henneman (1957) found that making information sometimes irrelevant and sometimes relevant will degrade performance. Detambel and Stolurow (1956) showed that lowering the conspicuity of irrelevant infornation interferes with the learning process. Namikas (1968) also found that training on a relevant dimension improved performance in the concept -2-formation transfer task. Interestingly enough, however, groups that were trained on irrelevant dimensions were not significantly different from those trained on neutral dimensions or those receiving no training. Katz (1968) applied the concept learning paradigm to the developmental effect of irrelevant dimensions. She found that while a degradation occurred in adults as a fu...