A method for calibrating the spatial coordinates of a visual display to high accuracy

High-resolution CRT displays are subject togeometric distortion: lines that are straight in the internal coordinates of the graphics software and hardware are curved when projected onto a plane in the observer’s line of sight. As the available resolution of CRT screens increases, it becomes more difficult to measure and correct for this distortion. We present a simple, highly accurate method for determining the mapping between internal coordinates and the viewing plane. It requires that an observer, using a calibration program, adjust triples of displayed points until they are collinear. A metal straightedge placed between the observer and the screen aids in this judgment. We describe the calibration of an IBM Enhanced Graphics Display in high-resolution mode (350 × 640 pixels), and illustrate how to use the estimated mapping to choose internal coordinates to draw undistorted figures that are accurate to within 0.5 pixel. The method can be used to assess or to correct the accuracy of visual displays. The method is relevant to experiments in spatial vision, spatial perception, perception of dot patterns, and any application in which geometrically accurate stimuli are required.     

Visual search along the colour dimension

Subjects searched for a chromatic target among coloured background items. With low target-background chromatic similarity, response latencies remained uniformly short whether the target was present or not and whether the items were chromatically homogeneous or not. Latencies increased with increases in target-background similarity and were longest with heterogeneous backgrounds, with which the effects of trial type also became manifest. We employed Treisman's model of visual search to account for these findings. In particular, we suggest that similarity increases forced a shift from a preattentive to an attentive search, the latter being importantly shaped by the background's level of chromatic variance.     

TEACHING CONVERSATION-RELATED SKILLS TO PREDELINQUENT GIRLS1

The use of conversation-related skills by youthful offenders can influence social interactions with adults. These behaviors are also likely to be useful to adolescents after their release from a treatment program (Journal of Applied Behavior Analysis, 1972, 5 , 343–372). Four girls, aged 13 to 15 yr, residing at Achievement Place for Girls in Lawrence, Kansas, received training on conversation-related behaviors. A multiple-baseline design across youths and across behaviors was used. Youth answer-volunteering in response to questions and three youth nonverbal components (“hand on face”, “hand at rest”, and “facial orientation”) were measured during daily 10-min sessions with a simulated guest in the group home's living room. Answer-volunteering was scored each session as the per cent of 13 “secondary” questions that the simulated guest did not have to ask following 10 “primary” questions. The three nonverbal components were scored according to their occurrence during 10-sec intervals and the resultant scores were averaged per session for an overall appropriate nonverbal score. The girls individually earned points within the home's token economy for participating in each session and additional points were awarded after training if preselected behavioral criteria were achieved for each of the two behavior categories per girl. Some of the training sessions were led by a “teaching-parent” (specially trained houseparent) while others were led by individual girls. Point consequences were administered by both the teaching-parent and by the “peer-trainers”. The average observed rate of answer-volunteering by the girls during pretraining sessions was 30% for S₁, 30% for S₂, 23% for S₃, and 68% for S₄. The average rate of answer-volunteering during posttraining sessions was: S₁ = 92%, S₂ = 89%, S₃ = 90%, and S₄ = 98%. The average nonverbal score during pretraining sessions was 82% for S₁, 53% for S₂, 60% for S₃, and 82% for S₄. The average nonverbal score during posttraining sessions was: S₁ = 98%, S₂ = 98%, S₃ = 98%, and S₄ = 100%. Videotapes of the sessions were shown in a random sequence to four adults (probation officer, social worker, etc who represented “significant others” for the youths' future success in the community. The adults judged posttraining tapes on the average as more appropriate 100% of the time for S₁, 100% of the time for S₂, 90% of the time for S₃, and 70% of the time for S₄. The study demonstrated that training of conversation-related skills is feasible with predelinquent girls, that the girls can help train each other, and that social validation of the training results is possible.     

Comparison of the distortion of probability information in decision under risk and an equivalent visual task

Decision makers typically overweight small probabilities and underweight large probabilities. However, there are recent reports that when probability is presented in the form of relative frequencies, this typical pattern reverses. We tested this hypothesis by comparing decision making in two tasks: In one task, probability was stated numerically, and in the other task, it was conveyed through a visual representation. In the visual task, participants chose whether a "stochastic bullet" should be fired at either a large target for a small reward or a small target for a large reward. Participants' knowledge of probability in the visual task was the result of extensive practice firing bullets at targets. In the classical numerical task, participants chose between pairs of lotteries with probabilities and rewards matched to the probabilities and rewards in the visual task. We found that participants' probability-weighting functions were significantly different in the two tasks, but the pattern for the visual task was the typical, not the reversed, pattern.     

The multi-factor structure of the Brief Self-Control Scale: Discriminant validity of restraint and impulsivity

The Brief Self-Control Scale (BSCS; Tangney, Baumeister, & Boone, 2004) was developed to assess dispositional self-control as it is conceptualized by contemporary theoretical perspectives; however, concerns regarding its unidimensionality and validity remain. This article addresses these concerns using three samples to define, confirm and test a multi-factor version of the BSCS. Results of Study 1 (n = 909) identified two factors of the BSCS: restraint and impulsivity. Results of Study 2 (n = 364) confirmed that the 2-factor structure fit the data well and performed better than 1-factor structures. Finally, results from Study 3 (n = 175) demonstrated the utility of the multi-factor BSCS in predicting self-reported affective and behavioral outcomes. Implications for research and theoretical development are discussed.     

The Role of Relational Contextual Cues versus Relational Coherence Indicators as Response Options on the Implicit Relational Assessment Procedure

The Psychological Record - Recent research has indicated that the results of the implicit relational assessment procedure (IRAP) may be affected by certain facets of the measure. The current...     

Parkinson’s Disease: Patients’ Knowledge,Attitudes, and Interest in Genetic Counseling

The objective of this study was to assess the genetics knowledge of patients with Parkinson’s disease (PD), and to explore their attitudes on genetic testing and interest in genetic counseling. We surveyed 158 patients from the University of Maryland Parkinson’s Disease and Movement Disorders Center. Patients averaged a score of 63% on general genetics knowledge and 73% on PD genetics knowledge. Participants had an overall positive attitude toward genetic testing: 80% believed that the use of genetic tests among people should be promoted, and 83% would undertake genetic test for PD if it was available. Patients reported a high interest to discuss the benefits, risks, and impacts of genetic testing for PD (mean sum score?=?26, range?=?9–35), and 43% patients expressed interest in meeting with a genetic counselor. Multivariate regression analysis showed that patients who had more positive attitudes toward genetic testing for PD were more interested in meeting with a genetic counselor (β?=?0.6, p?<?0.001). This study is the first to demonstrate an interest in genetic counseling among patients with PD. Our findings demonstrate a new niche for genetic counselors to support patients in clarifying gaps or misconceptions in knowledge about PD genetics as well as the possible risks, benefits, and limitations of genetic testing.     

Mathematics anxiety affects counting but not subitizing during visual enumeration

Individuals with mathematics anxiety have been found to differ from their non-anxious peers on measures of higher-level mathematical processes, but not simple arithmetic. The current paper examines differences between mathematics anxious and non-mathematics anxious individuals in more basic numerical processing using a visual enumeration task. This task allows for the assessment of two systems of basic number processing: subitizing and counting. Mathematics anxious individuals, relative to non-mathematics anxious individuals, showed a deficit in the counting but not in the subitizing range. Furthermore, working memory was found to mediate this group difference. These findings demonstrate that the problems associated with mathematics anxiety exist at a level more basic than would be predicted from the extant literature.     

Predicting land use voting behavior: expanding our understanding of the influence of attitudes and social norms

Voting to tax oneself in the current economic climate seems improbable. Framed in theories of normative influence and behavior change, this study tests the factors that predict voting for a county‐level millage (i.e., tax) to fund land preservation. Behavioral beliefs that contribute to people's attitudes toward the millage are identified and a model is tested with an expanded normative component. Results indicate that attitudes and subjective norms significantly predict voting intentions, and injunctive norms (i.e., people's perceptions of others' approval of taking an action) add significantly to the model's predictive power. Findings are reinforced by election results in which the millage proposal passed and can contribute to the applied literature by identifying social‐psychological factors that can be targeted with campaign messages.     

The modification of sentence structure and its relationship to subjective judgements of creativity in writing

The present study objectively defined and manipulated some compositional variables in 10-sentence stories written by fourth-, fifth-, and sixth-grade students, and related these operationally defined variables to subjective judgements of creativity. Points, exchangeable for candy and extra recess, were given to members of two teams contingent upon their using different adjectives, different action verbs, and different sentence beginnings. The students' use of these selected parts of speech was modified and the independent subjective ratings indicated that stories written during contingency conditions were generally rated as more creative than those written during baseline conditions. Operational definitions that specify non-repetition or variety of responses, and contingencies that require response diversity may provide a beginning basis for defining writing creativity and the conditions that maximize its occurrence.