Audience Design in Multiparty Conversation

How do speakers design what they say in order to communicate effectively with groups of addressees who vary in their background knowledge of the topic at hand? Prior findings indicate that when a speaker addresses a pair of listeners with discrepant knowledge, that speakers Aim Low, designing their utterances for the least knowledgeable of the two addressees. Here, we test the hypothesis that speakers will depart from an Aim Low approach in order to efficiently communicate with larger groups of interacting partners. Further, we ask whether the cognitive demands of tracking multiple conversational partners' perspectives places limitations on successful audience design. We find that speakers can successfully track information about what up to four of their partners do and do not know in conversation. When addressing groups of 3–4 addressees at once, speakers design language based on the combined knowledge of the group. These findings point to an audience design process that simultaneously represents the perspectives of multiple other individuals and combines these representations in order to design utterances that strike a balance between the different needs of the individuals within the group.     

Teaching dancercise to persons who are mentally handicapped: Programming transfer of stimulus control to a community setting

This study demonstrated procedures to promote the acquisition and transfer of stimulus control of an age-appropriate exercise skill. Three young adults diagnosed as mentally handicapped in a residential setting were taught a commercial dancercise routine during individual training sessions using a package of instructional procedures. A combination of a multiple baseline across subjects and a multiple baseline across response groups design showed that skill acquisition occurred only after each subject received training, and that performance did not generalize across exercise response groups. Training progressively incorporated more participants, new teachers, and new settings. Ultimately, subjects performed in a community dancercise class attended by 100 nonhandicapped persons.     

Functional classes and equivalence relations

Three adult subjects were taught a set of two-choice simultaneous discriminations, with three positive and three negative stimuli; all possible combinations of positive and negative stimuli yielded nine different pairs. The discriminations were repeatedly reversed and rereversed, the former positive stimuli becoming negative and the former negative stimuli becoming positive. With all subjects, a reversal of the contingencies for one pair of stimuli became sufficient to change their responses to all of the other pairs. The reversals had produced functional stimulus classes. Then, all subjects showed conditional discriminations emerging between members of a functional class; given a sample from one class and comparisons from both classes, they selected the comparison that was in the same class as the sample. Next, 2 of the subjects showed that the within-class conditional relations possessed the symmetric and transitive properties of equivalence relations; after having been taught to relate new stimuli to existing class members, the subjects then matched other class members to the new stimuli. Subsequent tests of two-choice discriminations showed that the conditional discriminations had transferred functional class membership to the new stimuli. The 3rd subject, who did not show equivalence relations among functional class members, was also found to have lost the within-class conditional relations after the equivalence tests.     

Temporal pattern of agonist-antagonist EMG activity during rapid limb movements in man

Analysis of elbow-extension movements, executed at maximal velocity, show positive correlations of timing of agonist-antagonist EMG activity with both movement velocity and displacement. Results indirectly support the notion that the antagonist musculature provides a braking force to arrest rapid limb movements.     

Task-related arousal of type A and type B persons: level of challenge and response specificity

To determine whether different levels of challenge had differential effects on the arousal levels of Type A and Type B persons, 30 Type A and 30 Type B male subjects worked on an intelligence test task (digits backwards recall) that was easy, moderately difficult, or extremely difficult. Arousal was measured in terms of systolic blood pressure, diastolic blood pressure, pulse rate, pulse volume, skin resistance, and subjective arousal. Results indicated that while working on the extremely difficult task, the Type A subjects evidenced reliably higher systolic blood pressure than did the Type B subjects (p = 0.1; difference = 7.52 mm of Hg) and that there were not reliable differences between the subjects in systolic blood pressure at other levels of challenge or on other measures of arousal.     

Analysis of Religious Bias among Christian Students in Science

Christians are notably underrepresented in science in part due to long-standing public perceptions of science-religion incompatibility and antireligious bias in science. This research explores whether undergraduates at a Christian university perceive and impose anti-Christian cultural stigma in science. Survey results from 126 biology students revealed that though students generally perceived the culture of science to be anti-Christian, they perceived Christians to have equal opportunities for scientific achievement. Results from a quasi-experimental audit study, in which students evaluated one of two profiles for mock prospective Ph.D. applicants (Christian or undisclosed faith) showed that students did not project anti-Christian stereotypes in terms of competence, hireability, or likeability, but showed some evidence of pro-Christian favorability. Together, this study suggests that the affirmational community of a Christian University may alleviate some negative impacts of anti-Christian stereotypes in academic biology, even as students perceive discrimination against Christians in science and atheists as more scientifically competent.     

MULTIDIMENSIONAL SCALING WITH A PRIORI DIMENSIONS

W aern Y. Multidimensional scaling with a priori dimensions. Scand. J. Psychol., 1972, 13 , 178–189.—This paper presents a method of multidimensional scaling by direct similarity estimates. The method is presented as an alternative to other multidimensional scaling methods, when hypotheses can be made concerning the dimensions underlying the perceptual variation. The method is used with five different sets of stimuli and compared, to an as to dimensions assumption-free component analysis, based on a vector model. The two methods resulted in similar configurations in most cases. One difference was found in a colour material, where the assumed dimensions could be regarded not to be orthogonal to each other. Here the a priori scaling revealed the assumed configuration as projected on the oblique axes whereas the component analysis could not give this information.     

Detection of extraneous signals during sentence recognition

In two separate experiments, 40 Ss were presented with recorded sentences during each of which a click occurred. Ss had to depress a key as soon as they heard the click. RTs were f aster when the click was located at the major syntactic break of the sentence compared with RTs to clicks not at a break. This confirmed the hypothesis that processing load is a function of the surface structure of sentences, although the role of minor breaks was not clear. A second finding was that RTs were slower when the click was in the first rather than in the second half of the sentence. This can also be explained in terms of differential processing loads.