Form recognition: Individual strategies in multivariate cue utilization

Twenty-five Ss were each presented 1,250 trials in a form-recognition task requiring S to find a form among 25 other forms on each trial. Fifty different eight-sided randomly derived polygons were used as stimuli, each presented in 25 different problems. Factors based on physical measures of the stimuli were correlated with observed latencies using multiple regression to assess cue-utilization strategies, while beta-weight profiles and intercorrelations of the Ss’ predicted latencies were used as indices of individual differences. Multiple correlations of physical-factor scores with observed latencies accounted for a significant proportion of the variance for all Ss, while between-S correlations of predicted latencies were never below .90. By all criteria employed, use of stimulus information was highly consistent among Ss. Replication of the experiment for one S revealed good reliability and nearly identical strategies.     

Differential Perceptions of College Environment: Student Personnel Staff and Students

The College Characteristics Index was administered to 160 randomly selected students, 15 head residents, and 20 members of the student personnel staff. Considerable disparity in perception of the environment was found among the 3 groups. Generally, students perceived the environment as possessing a greater degree of all the characteristics measured and valued by the academic community (i.e., aspiration level, intellectual climate, and academic achievement) than did the other reference groups. The differences in perceptions suggest that head residents and other student personnel staff may be involved with selected aspects of the campus life and with atypical groups of students.     

Student Patterns of Financing Education at a Land-Grant University

A financial aid survey was administered to the entire student body (10,185) at a land-grant university. The data showed that parental assistance was the main source of financial support, but that it declined in importance each year, while student employment by the university increased each year. Legislation providing increased opportunities for student employment appears to be appropriate and desirable. A wide variety of individual solutions to financial planning were noted.     

Parsing to Learn

Learning a language by parameter setting is almost certainly less onerous than composing a grammar from scratch. But recent computational modeling of how parameters are set has shown that it is not at all the simple mechanical process sometimes imagined. Sentences must be parsed to discover the properties that select between parameter values. But the sentences that drive learning cannot be parsed with the learner's current grammar. And there is not much point in parsing them with just one new grammar. They must apparently be parsed with all possible grammars, in order to find out which one is most successful at licensing the language. The research task is to reconcile this with the fact that the human sentence parsing mechanism, even in adults, has only very limited parallel parsing capacity. I have proposed that all possible grammars can be folded into one, if parameter values are fragments of sentential tree structures that the parser can make use of where necessary to assign a structure to an input sentence. However, the problem of capacity limitations remains. The combined grammar will afford multiple analyses for some sentences, too many to be computed on-line. I propose that the parser computes only one analysis per sentence but can detect ambiguity, and that the learner makes use of unambiguous input only. This provides secure information but relatively little of it, particularly at early stages of learning where few grammars have been excluded and ambiguity is rife. I consider three solutions: improving the parser's ability to extract unambiguous information from partially ambiguous sentences, assuming default parameter values to temporarily eliminate ambiguity, reconfiguring the parameters so that some are subordinate to others and do not present themselves to the learner until the others have been set. A more radical alternative is to give up the quest for error-free learning and permit parameters to be set without regard for whether the parser may have overlooked an alternative analysis of the sentence. If it can be assumed that the human parser keeps a running tally of the parameter values it has accessed, then the learner would do nothing other than parse sentences for comprehension, as adults do. The most useful parameter values would become more and more easily accessed; the noncontributors would drop out of the running. There would be no learning mechanism at all, over and above the parser. But how accurate this system would be remains to be established.     

A more recent look at the prevalence of stuttering in the United States

Data was requested from 50 states and 5 protectorate-trusteeships on: (1) the total school enrollment and (2) the number of stutterers identified each year between 1964–1973. The data are interpreted with reference to past prevalence figures. Trends within the 1964–1973 period are discussed. The study lends support to Van Riper's predicted declining prevalence of stuttering, yet there was no significant changes in incidence over the 10 year period.     

The word superiority effect: A comparison between restricted and unrestricted alternative set

Three experiments were conducted to investigate the word superiority effect (WSE) (Reicher, 1969). The first two experiments used mixed presentations of words and nonwords, and positional uncertainty of the critical letter. Experiment 1 used an unrestricted set of alternatives, while Experiment 2 used only two alternatives (R and L). Experiment 3 compared letter detection in nonwords with a restricted and unrestricted alternative set. WSE was found for both Experiments 1 and 2, at about the same level. Experiment 3 showed superior performance when alternatives were known in advance. It was concluded that context has an effect on letter recognition even with prior knowledge of alternatives if the critical position is not known in advance. Some incompatibilities between the present results and those of other investigators in the field are discussed.     

The relation of phenomenal brightness reversal and re-reversal to backward masking and recovery

Three recent experiments have demonstrated that a visual target suppressed through backward masking can be recovered by the introduction of a second mask. Present theories of backward masking cannot account for this since they assume that a masked target has no representation in the visual system. Amechanism is suggested to account for both visual backward masking and recovery in terms of lateral inhibition. Experimental evidenc e is offered in support of the hypothesized mechanism.