The distribution postulate in Bohm's theory

On Bohm's formulation of quantum mechanics particles always have determinate positions and follow continuous trajectories. Bohm's theory, however, requires a postulate that says that particles are initially distributed in a special way: particles are randomly distributed so that the probability of their positions being represented by a point in any regionR in configuration space is equal to the square of the wave-function integrated overR. If the distribution postulate were false, then the theory would generally fail to make the right statistical predictions. Further, if it were false, then there would at least in principle be situations where a particle would approach an eigenstate of having one position but in fact always be somewhere very different. Indeed, we will see how this might happen even if the distribution postulate were true. This will help to show how loose the connection is between the wave-function and the positions of particles in Bohm's theory and what the precise role of the distribution postulate is. Finally, we will briefly consider two attempts to formulate a version of Bohm's theory without the distribution postulate.     

Assessing Multicultural Counseling Competence: A Review of Instrumentation

The authors review four new instruments designed to assess multicultural counseling competence in trainees and practicing professionals. The Cross-Cultural Counseling Inventory—Revised (CCCI-R), the Multicultural Counseling Awareness Scale—Form B (MCAS:B), the Multicultural Counseling Inventory (MCI), and the Multicultural Awareness-Knowledge-and Skills Survey (MAKSS) were each critically reviewed in terms of item development, psychometric properties, and pragmatic utility. Specific research suggestions for continued empirical validation on the instruments are posited, and strong cautions regarding their current use in training are leveled.     

Social attitudes of schizophrenics

The Wilson-Patterson Conservatism Scale was given to 34 schizophrenic and 34 non-schizophrenic patients in a Dutch mental hospital. The absence of liberal-scoring schizophrenics was interpreted as consistent with the theory that the social withdrawal seen in chronic schizophrenia represents a strategy for coping with stimulus overload. Internal consistency analysis of C scale performance indicated that this test might be used to assess thought disorder in much the same way as the Bannister and Fransella Grid Test, but a great deal more economically. Furthermore, the questionnaire permits a more detailed examination of the source of inconsistency than does the repertory grid method.     

Note on preference for stimulus complexity across the life-span

Preference for stimulus complexity across the life-span was investigated with 175 females ranging in age from 17 to 72 yr. of age. Preference for complexity appeared to be age-invariant and monotonic function. Relationships to previous findings are discussed.     

The location of superfactors P, E and N within an unexplored personality factor space

Two questionnaires designed by Howarth (HPQ, APF2) whose factor space in unexplored and the EPQ (Eysenck) were jointly scale factored on 79 subjects, under the hypothesis that Eysenck's superfactors of P, E, and N should be represented as major influences in the resultant factor structure. A prinicipal component analysis yielded 7 factors from 24 by the Kaiser-Guttman and Scree Test, these 7 being rotated to a maximum simple structure by the Direct Oblimin procedure. Although failing to satisfy Bargmann's test of simple structure, this solution was accepted as adequate, noting the deficiencies og Bargmann's test and the efficiencies of the rotation method used. Within the 7 factor solution, P, E, and N were seen to be located as factor numbers 2, 3 and 1, respectively. One interesting detail is that a sociability primary loaded with an impulsivity primary on the Extraversion factor contrary to Guilford's (1977) arguments for the independence of these primaries. It is concluded that Eysenck's assertion of the enduring stability and breadth of the PEN factor triad has been upheld.     

A reconsideration of testing for competence rather than for intelligence.

David C. McClelland's 1973 article has deeply influenced both professional and public opinion. In it, he presented five major themes: (a) Grades in school did not predict occupational success, (b) intelligence tests and aptitude tests did not predict occupational success or other important life outcomes, (c) tests and academic performance only predicted job performance because of an underlying relationship with social status, (d) such tests were unfair to minorities, and (e) "competencies" would be better able to predict important behaviors than would more traditional tests. Despite the pervasive influence of these assertions, this review of the literature showed only limited support for these claims.     

Stability and skill in driving

Two experiments addressed the relation between postural stability, perceptual sensitivity, and stability of driving performance. A vehicle was fitted with differential GPS for measuring position and speed, position sensors for measuring brake and accelerator depression, force transducers for measuring door, console and footrest bracing forces, and an accelerometer for measuring the 3D accelerations of the vehicle. In Experiment 1, we investigated whether the initiation of deceleration and the control of braking might be due to sensitivity to the perceptual variable tau, which specifies time-to-contact (TTC), and in particular, whether its first derivative, tau-dot, is used to maintain a constant deceleration profile. Using both untrained experienced drivers (EDs) and trained driving instructors from the Holden Performance Driving Centre (HPDC), results confirmed that, regardless of skill level, tau-dot was maintained at a value close to 0.5 and, as predicted by Lee [Perception 5 (1976) 437], braking was initiated when TTC approximately 5 s. In Experiment 2, we wished to quantify the purported differences in driving behaviour between EDs and HPDC instructors during a variety of everyday manoeuvres. Results indicated that instructors utilised a different cornering trajectory, a different emergency braking strategy, and were able to perform a high-speed swerve and recovery task more effectively than the EDs. In general, the instructors applied greater bracing forces using the door and console compared with EDs. The instructors also applied greater footrest forces during emergency braking than did the EDs. The greater use of bracing by instructor drivers to resist g-forces represents a strategy of active stabilisation that enhances both postural stability, as well as overall stability and consistency of driving performance. Results are discussed with regard to the dynamics of perceptual-motor coordination, and how increased stability might improve sensitivity to relevant perceptual information. We conclude that driver-training programmes that focus on increasing driver stability (as a pre-requisite for increased control) show great promise as a means to improving one's attention during driving, and hence have the potential to dramatically improve road safety in general.