Bootstrapping while barefoot (crime models vs. theoretical models in the hunt for serial killers)

Investigating random homicides involves constructing models of an odd sort. While the differences between these models and scientific models are radical, calling them models is justified both by functional and structural similarities. Serial homicide investigations illustrate the marked difference between theoretical models in science and the models applied in these criminal investigations. This is further illustrated by considering Glymourian bootstrapping in attempts to solve such homicides. The solutions that result differ radically from explanations in science that are confirmed or disconfirmed by occurrences. Unlike the scientist, the flatfoot gumshoe is also barefoot: he is bereft of a general, determinative theoretical frame. This result shows that criminal investigations do not apply science in the Galilean sense.I wish to thank philosophers Keith Cooper, William Wimsatt, and, especially, Jay Bachrach for helpful comments on earlier versions of this paper.     

Development and psychometric validation of the verbal affective memory test

We here present the development and validation of the Verbal Affective Memory Test-24 (VAMT-24). First, we ensured face validity by selecting 24 words reliably perceived as positive, negative or neutral, respectively, according to healthy Danish adults’ valence ratings of 210 common and non-taboo words. Second, we studied the test's psychometric properties in healthy adults. Finally, we investigated whether individuals diagnosed with Seasonal Affective Disorder (SAD) differed from healthy controls on seasonal changes in affective recall. Recall rates were internally consistent and reliable and converged satisfactorily with established non-affective verbal tests. Immediate recall (IMR) for positive words exceeded IMR for negative words in the healthy sample. Relatedly, individuals with SAD showed a significantly larger decrease in positive recall from summer to winter than healthy controls. Furthermore, larger seasonal decreases in positive recall significantly predicted larger increases in depressive symptoms. Retest reliability was satisfactory, rs?≥?.77. In conclusion, VAMT-24 is more thoroughly developed and validated than existing verbal affective memory tests and showed satisfactory psychometric properties. VAMT-24 seems especially sensitive to measuring positive verbal recall bias, perhaps due to the application of common, non-taboo words. Based on the psychometric and clinical results, we recommend VAMT-24 for international translations and studies of affective memory.     

On measuring selective attention to an expected sensory modality

Perceptual judgments can be affected by expectancies regarding the likely target modality. This has been taken as evidence for selective attention to particular modalities, but alternative accounts remain possible in terms of response priming, criterion shifts, stimulus repetition, and spatial confounds. We examined whether attention to a sensory modality would still be apparent when these alternatives were ruled out. Subjects made a speeded detection response (Experiment 1), an intensity or color discrimination (Experiment 2), or a spatial discrimination response (Experiments 3 and 4) for auditory and visual targets presented in a random sequence. On each trial, a symbolic visual cue predicted the likely target modality. Responses were always more rapid and accurate for targets presented in the expected versus unexpected modality, implying that people can indeed selectively attend to the auditory or visual modalities. When subjects were cued to both the probable modality of a target and its likely spatial location (Experiment 4), separable modality-cuing and spatial-cuing effects were observed. These studies introduce appropriate methods for distinguishing attention to a modality from the confounding factors that have plagued previous normal and clinical research.     

On the spatial extent of attention in object-based visual selection

A new test was devised to avoid previous confounds in measures of object-based limits on divided visual attention. The distinction between objects was manipulated across a wide spatial extent. Target elements appeared on the same object only when far apart, and appeared close only when on different objects, so that object effects could not be reduced to spatial effects, nor vice versa. Subjects judged whether two odd elements within a display of two dashed lines were the same or different. They performed better when the target elements were far apart on a common line rather than on two distinct lines, even though the latter arrangement was more likely. Thus, nonstrategic object-based limits on divided attention can arise even across large distances. However, when subjects were precued to expect targets in a narrow region of the display, the object effect was eliminated, implying that object-based selection may only operate within spatially attended regions.     

BEHAVIORAL COMMUNITY PSYCHOLOGY: ENCOURAGING LOW-INCOME PARENTS TO SEEK DENTAL CARE FOR THEIR CHILDREN1

The present study examined the effectiveness and cost efficiency of three different techniques to encourage low-income rural parents to seek dental care for their children. The families of 51 children who needed immediate dental care (determined by dental screening at a local school) were placed into three matched groups and randomly assigned to the treatment conditions: One Prompt (Note Only), Three Prompt (Note, Telephone Contact, Home Visit), and One Prompt plus $5 Incentive. The Three Prompt and One Prompt plus $5 Incentive were significantly more effective in initiating dental visits than the Note-Only procedure. Not only was the One Prompt plus $5 Incentive technique effective in producing a slightly larger percentage of initial dental visits compared to the Three-Prompt technique, it also produced a significantly larger number of followup visits. Furthermore, the cost-effectiveness analysis showed the Incentive condition to be less costly than the Three-Prompt condition in encouraging initial dental visits.     

A PERFORMANCE-BASED LOTTERY TO IMPROVE RESIDENTIAL CARE AND TRAINING BY INSTITUTIONAL STAFF

Two experiments were conducted on four units of a residential facility for the multiply-handicapped retarded in an attempt to improve daily care and training services. Experiment I compared the effects of two procedures in maintaining the work performance of attendants, using an A-B design on two units. One procedure consisted of implementing specific staff-resident assignments, the other consisted of allowing attendants who had met performance criteria to be eligible for a weekly lottery in which they could win the opportunity to rearrange their days off for the following week. Results showed that the lottery was a more effective procedure as measured by the per cent of time attendants engaged in predefined target behaviors, and by their frequency of task completion in several areas of resident care. Experiment II replicated and extended these results to the area of work quality on two additional units, using a multiple-baseline design. The performance lottery was found to be an effective economical procedure that could be implemented by supervisory staff on a large scale.     

Paired comparisons with individual differences

A model of Bradley-Terry type for paired comparisons is considered. In addition to the usual parameters, the model allows for individual parameters and corresponding parameters for the choice-alternatives. The model is applied to a set of data from a Danish investigation of the attitude of blue collar workers towards alternative social gains. The proposed model is finally compared to a model recently suggested by Schönemann and Wang.