A note on the analysis of designs in which subjects receive each stimulus only once

In social psychological experiments, the manipulations of interest are often presented to subjects along with, or as part of, some stimulus. An example would be a manipulation of the verbal label associated with a stimulus photograph, in a person perception study. Ordinarily it is not possible for stimuli to be completely crossed with treatments because subjects cannot be exposed to any stimulus more than once. In such designs it is wise to counterbalance the assignment of stimuli to treatment conditions, but this gives rise to difficulties in the analysis of the experimental data. Data from such designs have frequently been misanalyzed in the published literature. This paper presents a method of constructing a counter-balancing scheme to simplify the analysis, and appropriate methods of analysis for both the simplified and the general case. It is emphasized that stimuli are generally best treated as a random factor in such designs, permitting increased generalizability, but the case where the stimulus factor is fixed is also considered.     

Reducing fears and increasing assertiveness: The role of dissonance reduction

In the research paradigm known as effort justification, people engage in an effortful activity in order to attain a goal. As a result, the goal becomes more attractive. Two experiments were conducted to test the notion that the effort justification sequence can account for the positive changes that result from psychotherapy. In the first experiment, subjects who were afraid to approach a snake underwent one of two types of effortful therapy. One was a modified form of an anxiety-producing therapy known as “implosive therapy”; the other was merely a set of physical exercises. It was reasoned, on the basis of cognitive dissonance theory, that the expenditure of effort would lead to a positive change in the ability to approach the snake but only under conditions of high decision freedom. Half of the subjects in each of the therapy conditions participated with high choice; the other half with low choice. Subjects' improvement in their approach to snakes was assessed. A main effect for decision freedom was predicted and found independently of the type of effort that subjects expended. A second experiment conceptually replicated the findings of the first experiment. Subjects who wanted to become more assertive participated in an effortful, physical exercise therapy or in a modified form of the standard treatment for fear of assertiveness. The results of the 2 × 2 factorial experiment again showed a main effect for decision freedom such that high choice subjects became more assertive. The findings were discussed in terms of dissonance and attribution theories as well as for implications for future consideration of psychotherapy.     

The effects of base rates and individuating information on judgments about another person

Past research suggests that in judging a person's category membership, people largely ignore the population frequency of membership in the category (base rates) in favor of individuating information about the particular person. This study tested the hypothesis that base rates will be utilized to the extent that the usefulness of the individuating information for diagnosing category membership is diminished. Subjects were given problems in which both base rates of membership in each of two categories and individuating information about a target person were presented. Then, in each case, they were asked to assess the probability that the target person belonged to each category. In three sets of problems, the diagnostic usefulness of the individuating information (personality characteristics) was diminished by including individuating information that was either inconsistent or irrelevant, or by increasing the similarity of the two alternative membership categories. In a fourth set of problems, the individualistic information included consistent, relevant personal characteristics and the membership categories were dissimilar. As expected, base rates were used in each of the first three sets of problems but were ignored in the fourth set. The results were interpreted in terms of informational factors that induce a shift away from a habitual, spontaneous reliance on a source of information (e.g., personality traits) for which one has well-developed rules (e.g., intuitive personality theories), and toward a more controlled, deliberate mode of thinking wherein other sources of information (e.g., base rates) are attended to and incorporated into judgment through less frequently used rules (e.g., sampling rules).     

Attributed influence: The importance of observing change

The presence of a target's unexpected change in behavior following an influence attempt was hypothesized to be a critical variable for attributing influence to a particular agent. Observers read a brief story in which an agent's intervention was followed by the target's compliance, noncompliance, or countercompliance to the request. The results indicated that influence was attributed to the agent in the conditions demonstrating change, i.e., compliance and countercompliance, regardless of the direction of that change. Additional findings indicated that influence attributed to an agent decreased if the target delayed final compliance with the intervention.     

The development of grapheme-phoneme correspondence in normal and dyslexic readers

The present experiment was concerned with the development of grapheme-phoneme conversion ability in normal and reading-age matched dyslexic readers. The use of grapheme-phoneme correspondences was observed in a recognition memory task for pronounceable nonwords. The nonwords were presented in either the visual or auditory modality and had to be recognized immediately from the converse modality, thus necessitating decoding of stimuli across modalities. The use of grapheme-phoneme correspondences increased with reading age in the normal readers but not in the dyslexics. It was postulated that dyslexics have a specific difficulty in grapheme-phoneme conversion. For them an increase in reading age is attributable mainly to an increase in size of sight vocabulary.     

The development of linear syllogistic reasoning

Between 24 and 26 children in each of grades 3, 5, 7, 9, and 11 (with mean ages of 8.5, 10.2, 13.0, 15.0, and 16.6 years, respectively) were tested in their ability to solve linear syllogisms, problems such as “John is taller than Mary. Mary is taller than Pete. Who is tallest? John, Mary, Pete.” Response latencies and error rates decreased across grade levels and sessions. Component latencies also generally decreased with increasing age. Four alternative information-processing models were fit to the group latency data at each grade level. These models were (a) a spatial model, according to which people represent the terms of a linear syllogism in the form of a linear spatial array; (b) a linguistic model, according to which linear syllogisms are solved via inferences on functional relations represented by linguistic deep structures; (c) an algorithmic model, according to which people solve linear syllogisms by applying a series of simple, essentially mechanical steps, and (d) a mixed model, which combines selected features of the spatial and linguistic models, and adds new features of its own. The latency data supported the mixed model at each grade level, although in grade 9 the model was not the preferred one until the second session of testing.     

Facilitating referential communication among children: The listener as teacher

This study was designed to test the hypothesis that systematic variations in listener behavior can have an important influence on both speaker behavior and communicative success among children. In particular, we investigated the idea that systematic variations in listener behavior might have not only within-trial effects on the adequacy of speakers' messages and the accuracy of communication among children, but also cumulative effects on speakers' initial messages across trials. Effects of stimulus complexity were also examined. Pairs of 7- and 9-year-old children participated in a referential communication game, with the younger child serving as speaker and the older one as listener. Half of the listeners were given a plan for effective listening which emphasized the importance of asking questions if the speakers' messages were ambiguous. Replicating earlier findings, the plan manipulation was successful in encouraging listeners to ask questions when necessary. The major result was that listener questions not only had the expected trial-by-trial effect on message adequacy and communicative accuracy, but also showed a cumulative effect on speaker performance. When exposed to systematic listener feedback, speakers improved their initial messages over trials. Stimulus complexity was not a major determinant of performances. These findings suggest that provision of systematic listener feedback may be an effective method for teaching speaker skills to young children.     

Categorical and spatial modes of representation in young children's recall

Preschool children aged 4 and 6 were asked to recall a set of line drawings under two conditions: pictures blocked in category groups, and pictures blocked in noncategory groups. For 4-year-olds, the blocking condition made no difference in the structure of their recall; but for the 6-year-olds, the category blocking served as a support for category clustering of their recall lists. No purely spatial clustering appeared at either age. It was concluded that 6-year-olds' use of classes is closely linked to concrete spatial arrangement of objects.     

Self-assessment,self-enhancement,and task preference

If task choice depends on a person's interest in the accurate assessment of his or her abilities, task attractiveness should be positively related to the diagnosticities of all performance outcomes with regard to one's ability level. In contrast, the view that people are primarily interested in maximizing pride or mininizing shame would predict that task attractiveness is positively related to the diagnosticity of success but negatively related to the diagnosticity of failure. To test these predictions, subjects were presented with tasks that varied orthogonally in the extent to which success was diagnostic of high ability level and the extent to which failure was diagnostic of low ability level. Consistent with the self-assessment view, task attractiveness increased both with the diagnosticity of success and with the diagnosticity of failure. Furthermore, both effects were more pronounced for high achievement motive subjects than for low achievement motive subjects. This result lends support to the self-assessment view, which assumes that high achievement motive subjects are more interested in attaining the ability-relevant information contained in any performance outcome.     

Commitment and satisfaction in romantic associations: A test of the investment model

Two experiments were designed to test the adequacy of the investment model of developing relationships in predicting satisfaction with and commitment to ongoing associations. According to the investment model, attraction to and satisfaction with a relationship is a function of a comparison of the relationship outcome value (both rewards and costs) to the individual's expectations, or comparison level. Commitment to a relationship is said to be a function not only of the relationship outcome value, but also the quality of the best available alternative and the magnitude of the individual's investment in the relationship. The intrinsic or extrinsic investment of resources serves to increase commitment by increasing the costs of leaving the relationship. Thus, increases in investment size, decreases in alternative value, and increases in relationship value should increase commitment to an ongoing relationship. In Experiment 1, a role-playing study, commitment to relationships increased with intrinsic and extrinsic investment size and decreased with the value of alternatives, but was not appreciably affected by relationship costs. Satisfaction/attraction significantly increased as relationship costs decreased. In Experiment 2, a survey of ongoing romantic associations, satisfaction/attraction was predicted by relationship reward value and relationship cost value. Commitment to relationships increased as relationship reward value and investment size increased and as alternative value and relationship cost value decreased, although the effects of cost value were weak.