Interpolation in structure from motion

We investigated surface interpolation in displays of structure from motion (SFM). To do so, we introduced a new method for measuring surface perception in dynamic displays—theSFM probe. An SFM probe is a dot that moves rigidly with the dots on a simulated surface, and whose distance from that surface can be adjusted with a joystick or similar control. The displays we studied were random-dot cylinders containing a vertical strip devoid of feature points (thegap). Subjects adjusted an SFM probe, presented in the gap, until the probe dot appeared to be on the surface. Variability in probe-dot placement decreased with increasing texture density on the cylinder and increased with increasing gap width. Subjects showed a consistent bias to place the probe dot outside the cylinder. This bias increased with increasing texture density for the SFM displays. (The opposite bias was found in a static two-dimensional interpolation task with an arc whose curvature matched that of the cylinder: Subjects placed the probe dot inside the arc.) This outside bias is inconsistent with several theoretical approaches to surface interpolation.     

Behavioral consequences of song learning: Discrimination of song types by male white-crowned sparrows

The functional significance of learned population differences in male song in the white-crowned sparrow was explored in natural populations using playback tests. Laboratory results have shown that learning of the population-specific song seems to take place in early life and is strongly dependent upon the nature of the auditory experience at that time. However, the varied results of recent studies make it difficult to reach a confident conclusion about the ecological functions of song learning. The present research took advantage of naturally occurring variation in the differences between songs of adjacent populations to determine a function relating degree of difference in song to intensity of territorial singing elicited. Applying a typological evaluation of syllable structure to the four segments of the song allowed a crude quantitative ranking of the differences between local songs and playback stimuli. These results, together with those of other studies, suggest a unimodal aggressive response function of males to songs of other males. A maximum response to songs slightly different from the local song environment suggests that male exclusion based upon acquired song components may contribute to the maintenance of discrete and stable song dialects.     

The pastor and his privacy

Pastoral Psychology -     

Employment rejection and acceptance letters and their unintended consequences on image,self-concept,and intentions

This paper demonstrates that the positiveness and negativeness of letters of acceptance and rejection from companies have an impact on company image, self-concept of recipient, and reported future intentions of potential recruits. The implication for employers writing letters of acceptance and rejection is that they should communicate with prospective recruits in a positive manner no matter what the letter's message. Positive rejection letters can mitigate effects of rejection and negative acceptance letters can impair the positiveness of acceptance.This research was partially supported by Grant #82037 from the Purdue Agricultural Research Station. Reprints should be addressed to Dr. Richard Feinberg, Department of Consumer Sciences and Retailing, Purdue University, 1262 Matthews Hall, West Lafayette, IN 47907-1262.     

The effects of observation on emotional arousal and affiliation

This study assessed the influence of anticipated experimenter surveillance during the performance of a painful or potentially embarrassing act on affiliative preferences before engaging in that act. As predicted, there was an overall preference for isolation when the act to be performed was embarrassing, and this tendency increased with anticipated surveillance. There was an overall preference for affiliation under fear arousal, and this preference also increased with anticipated surveillance. Contrary to previous research, whether or not the potential affiliate was a subject in the experiment (i.e., in a similar or dissimilar emotional state) did not affect these tendencies. Possible ways of accounting for these findings are discussed.     

Perceived direction of rotation of simulated three-dimensional patterns

Direction of rotation judgments were obtained from 72 subjects for computer-generated dot patterns simulating points randomly distributed in a sphere rotating about a vertical axis. The displays were produced either with normal polar projections or with perspective effects limited to the horizontal or to the vertical dimension of the projection. The simulated viewing distance used in the projections and the visual angle subtended by the projected displays were also varied. Accuracy of direction judgments was about the same with perspective effects limited to the vertical dimension as with normal polar projections but did not exceed chance expectations with perspective effects limited to the horizontal dimension. Accuracy was lower at the greater simulated viewing distance and at the greater visual angle.     

Perceptions of personal control and conformity of vocational choice as correlates of vocational development

This study examined differences in vocational maturity of women across different levels of internal-external control and typical versus atypical vocational choice. It was predicted that internally controlled women would have higher vocational maturity scores than externally controlled women; women who make atypical vocational choices would have higher vocational maturity scores than women who make typical choices. Data from the Attitude Scale of Crites' Career Maturity Inventory, MacDonald and Tseng's I-E Scale, and dichotomized ratings of typical versus atypical vocational choice were obtained from 179 freshmen to senior female student volunteers in a large New England university. Analysis of variance indicated that internally controlled women had significantly higher vocational maturity than externally controlled women (p <. 01); no differences were found in vocational maturity between those making typical or atypical vocational choices; the lowest level of vocational maturity was found for externally controlled females making atypical vocational choices. Implications of these findings for counseling are discussed.