A Two-Detector Signal Detection Analysis of Learning to Use Alarms

The learning to use (or disregard) alarms was analyzed in an experiment in which participants had to decide whether a simulated system was intact or malfunctioning, based on the reading of a gauge-like display. In two of the three experimental conditions participants received a warning when the system, that functioned as a signal detector with the same sensitivity as the participant, detected a value that was beyond a preset response criterion (which was either lnβw = −1 or lnβw = .5). Results showed that participants' responses were always less cautious than the optimal setting. Already in the first 100 trial block (out of 5) existed clear differences between the warning conditions, as well as differences between the no-warning condition and a warning condition for which the optimal β were the same. These results indicate that the learning process has two components—first a rapid adjustment of the response to the condition, and than a slow, and in some conditions non-existing, convergence towards the optimum.

Gender Differences during Processing of the Stroop Task

An assertion was made that “There are no sex differences in Stroop interference” (MacLeod, 1991, p. 203) in spite of some evidence to the contrary (e.g., Sarmany, 1977). To resolve the discrepancy, this study examined the nature of gender differences in the context of other variables. 8 men and 8 women were tested, using response speed and errors made as dependent measures. Independent variables were gender, perceptual input (Stroop) task, congruency of stimuli, manual response output, and trial block. Contrary to MacLeod, men were consistently slower than women over trial blocks by some 46 msec., although their error rates did not differ significantly. Response output interacted with gender, with Stroop task, and with trial block. Congruent stimuli were processed faster than incongruent ones. Differences may be ascribed to greater verbal and fine motor abilities of women and greater spatial ability of men.

Effect of Visual and Verbal Post-Response Errors on Learning a Simple Discrete Task

Visual and verbal post-response errors were manipulated to determine if acquisition of a motor skill (linear positioning) varied. Three 2 (types of error information) × 4 (trial blocks) factorials were used to analyze data specific to absolute, constant, and variable errors in movement accuracy. Both groups given information on errors significantly reduced movement errors over trial blocks. A significant interaction of absolute and variable errors favored the verbal presentation only on the first trial block.

Effects of Praise and its Source on Performance

Catano's (1975) study was replicated to assess the effects of the experimenter's vs peers' praise and also the shift from quality to quantity in performance as a function of praise. 60 undergraduates worked on one of two designs in a mirror-tracing apparatus. They received either no praise, praise from the experimenter, or praise from a student assistant (peer condition). Performance (error rate) in the experimenter-praised group on both tasks was superior only to the peer-praised condition and showed improvement both in speed and accuracy. Source of praise and trial-block sequence in times for task completion interacted. Source of praise influenced both quality and quantity of performance.

Reversal- and Non-Reversal-Shift Discrimination Learning as a Function of Drive in Albino Rats

Drive level affected reversal rather than non-reversal-shift learning during initial shift-discrimination trials. Animals under high water deprivation during the original simultaneous discrimination and reversal-shift discrimination made more initial (first trial-block) errors during reversal-shift than animals that were maintained on moderate deprivation during either or both discrimination tasks.

Behavior in a Mixed Motive Game as a Function of Induced Self-Esteem

High, neutral, and low self-esteem were induced in college students who then took part in a mixed motive game. It was hypothesized that induced low self-esteem would result in highly competitive behavior. This prediction was confirmed for the first trial block of 10 trials but no difference in competitive behavior among the 3 groups was observed during the second through fifth trial blocks. The results were discussed in terms of the success of the induction of level of self-esteem, the perceived strategy of the other player, and the way in which the perceived strategy might interact with chronic and induced levels of self-esteem.

Effect of Altered Likelihood Values upon Information Use

60 Ss were run in a 2 × 2 design, in which Ss were given three successive 20-trial blocks of choice alternatives for which the probability of the cue provided being correct was markedly different during the second 20-trial block, being high if the first and third were low, or vice versa. The other major independent variable was number of alternatives. Data were compared with Ss run under identical conditions without any interpolated changes in cue probability. The following conclusions were reached. The effect of experience is to shift behavior in the direction of a statistically more advantageous strategy. This effect is relatively small in the present situation because of the low risk nature of the experimental situation.