The effect of subject's race and other's race on judgments of causality for success and failure

This study examined the proposition that blacks and whites make dispositional attributions for an in-group's positive behaviors and an out-group's negative behaviors. The study also examined whether this positive in-group bias was caused by dislike of the out-group or belief in a stereotype. Thus, blacks and whites made attributions to black and white others who succeeded or failed on tasks for which there was either no stereotype or a more negative stereotype of whites than of blacks. An out-group other's failure on both tasks was attributed to lack of ability more than was an in-group other's failure. This finding suggests that the in-group bias is caused by dislike of the out-group. Furthermore, in success conditions subjects' attributions to the in-group or out-group other did not differ. It was suggested that these attributions may result from a combination of an in-group bias and a polarized appraisal.     

Functional constraints on sentence processing: A cross-linguistic study

English and Italian provide some interesting contrasts that are relevant to a controversial problem in psycholinguistics: the boundary between grammatical and extra-grammatical knowledge in sentence processing. Although both are SVO word order languages without case inflections to indicate basic grammatical relations, Italian permits far more variation in word order for pragmatic purposes. Hence Italians must rely more than English listeners on factors other than word order. In this experiment, Italian and English adults were asked to interpret 81 simple sentences varying word order, animacy contrasts between the two nouns, topicalization and contrastive stress. Italians relied primarily on semantic strategies while the English listeners relied on word order—including a tendency to interpret the second noun as subject in non-canonical word orders (corresponding to word order variations in informal English production). Italians also made greater use of topic and stress information. Finally, Italians were much slower and less consistent in the application of word order strategies even for reversible NVN sentences where there was no conflict between order and semantics. This suggests that Italian is ‘less’ of an SVO language than English. Semantic strategies apparently stand at the ‘core’ of Italian to the same extent that word order stands at the ‘core’ of English. It is suggested that these results pose problems for claims about a ‘universal’ separation between semantics and syntax, and for theories that postulate a ‘universal’ priority of one type of information over another. Results are discussed in the light of the competition model, a functionalist approach to grammar that accounts in a principled way for probabilistic outcomes and differential ‘weights’ among competing and converging sources of information in sentence processing.     

Two classes of models for magnitude estimation

One class of models assumes that presentation of a signal results in an internal representation as a random variable. Depending on whether the signal is close to or far from the preceding signal, the variance of the representation is smaller or larger. Responses are determined largely by this random variable; however, when the signal is close to the preceding one, the response is generated by modifying the representation multiplicatively by some function of the ratio of the previous response to its representation. Power and linear functions are explored. The form of the random variable is assumed to be that arising from either the timing or the counting model operating on a Poisson process. Detailed analyses are carried out successfully only for the timing model with neural sample sizes independent of intensity; however, the data require the sample to increase with intensity. The linear response function coupled with the constant sample size counting model appears somewhat viable, but detailed calculations are very difficult to carry out. The second class of models postulates a power function relation between magnitude estimates and signals intensity for which the exponent is a Gaussian distributed random variable and the unit is the product of two log normal random variables. Again we assume an attention band such that succesive stimuli that are widely separated in intensity lead to independent samples of the random variables while a variety of assumptions is explored for successive stimuli that are near each other in intensity. Although they each give rise to the qualitative features of the data, estimates of parameters are sufficiently inconsistent that we are led to reject all of the submodels studied.     

The effect of unequal group size on Tukey's HSD procedure

A limitation of the Tukey HSD procedure for multiple comparison has been the requirement of equal number of observations for each group. Three approximation techniques have been suggested when the group sizes are unequal. Each of these techniques was empirically analyzed to determine its effect on TypeI error. Two of the considered variables, average group size and differences in group size, caused differing actual probabilities of TypeI error. One of the three techniques (Kramer's) consistently provided actual probabilities in close agreement with corresponding nominal probabilities.     

The effects of figurai shape on the perception of area

It was hypothesized that figures of equal area and different shapes are perceived as differing in area and that these apparent differences in area are due to the interaction of certain shape variables. Thirty figures were presented to 45 Ss for paired comparisons. Forty-five sets of 30 Choice scores were calculated. The performance of each S was tested for consistency by the Method of Circular Triads (p>.01). A Coefficient of Agreement (u) indicated that the Ss agreed among themselves (p>.01). Fifteen Ss were tested twice for test-retest reliability (p>.01). The 45 sets of Choice scores were then converted to rank values and averaged over all Ss. The mean rank values of the 30 figures were treated with the two-way analysis of variance by ranks to determine the significance of the differences among them (p>.01). A Coefficient of Concordance (W) was calculated on the 45 sets of rank values to support the results of the analysis of variance (p>.01). Subsequently, the 30 mean rank values were treated as the dependent variable in a multiple correlation (R) with the shape variables as the independent variables (p>.01). The apparent area of the figures was found to vary inversely with perimeter, number of turns, breadth, and external area.     

A stochastic model for free recall

A statistical model for verbal learning is presented and tested against experimental data. The model describes a Markov process with a realizable absorbing state, allowing complete learning on some finite trial as well as imperfect retention prior to this trial.This work was carried out while the author was at Lincoln Laboratory, Massachusetts Institute of Technology.Operated with support from the U. S. Army, Navy, and Air Force.