Conjunctive Decisions in a Paper-and-Pencil Task

Many situations can have a significant effect on response time. Some situations affecting response time require union decisions - decisions based on the 'or' rule. The Hick-Hyman law, as well as Sternberg's linear relationship, are based on union decisions. Most situations in the real world, however, are based on intersection or 'conjunctive' decisions - decisions based on the 'and' rule. The relationship between conjunctive decisions and reaction time is examined in the present research. One question this study attempted to answer is whether there is a functional relationship between mean response time and display size. The study consisted of 139 students. A factorial between-subjects design was incorporated to compare response time with varying positive set sizes and display sizes based on conjunctive decisions. Each student was assigned a positive set of characters ( 1, 2, 3, or 4 letters) and a display set of characters ( 6, 8, or 10 letters) that remained constant throughout the experiment. The subjects were presented with a total of 120 different displays (10 pages of 12 displays each). With each presentation of the display set, the subject made a decision as to whether or not the display set contained all items from the positive set regardless of order. The response data were analyzed using a 4 X 3 (Positive Set Size by Display Size) factorial design. Three main effects and one two-way interaction were statistically significant at the p < .05 level. These three main effects and one two-way interaction were display set size, positive set size, page number, and positive set size by page number, respectively. The results support Sternberg's research on serial and parallel processing, as well as the hypotheses posed on conjunctive decisions and response time. The results are discussed in terms of the role the independent variables play on the subject's conjunctive decision processing and response time.