The computation of discrimination values

Results have been reported showing the usefulness of discrimination value in automatic construction of dictionaries for information retrieval. While discrimination value is defined in the literature, no specific explanation of its computation is given. In this paper the computation of discrimination value is discussed, a relatively efficient algorithm is presented and an example is given.     

Smooth-pursuit eye movements in the newborn infant.

The capacity of newborn infants to smooth-pursuit eye movements in single-target tracking and in optokinetic nystagmus to a moving striped field was examined utilizing DC electrooculography. Smooth-pursuit movements were observed in all infants who were alert during testing, but they occupied less than 15% of viewing time during single-target tracking. The velocity of smooth-pursuit segments in single-target tracking increased linearly to a target velocity of 19 degrees/sec and deteriorated rapidly at faster speeds. No smooth pursuit occurred above 32 degrees/sec in single-target tracking. By contrast, optokinetic nystagmus was observed at all field velocities to 40 degrees/sec, but the speed of the mean slow component increased linearly to 25 degrees/sec and diminished above that field velocity. Infant optokinetic nystagmus differed strikingly from that of adults in that tonic ocular deviation was in the direction of field movement rather than away from it. This feature of neonatal optokinetic nystagmus is consistent with deficient foveal function and suggests that the relatively poor smooth-pursuit performance of newborns may be related to foveal immaturity.     

Do Fourteenth Amendment considerations outweigh a potential state interest in mandating cochlear implantation for deaf children?

Currently, the decision concerning pediatric cochlear implantation for children remains a personal choice for parents to make. Economic factors, educational outcomes, and societal attitudes concerning deafness could result in an increased governmental interest in this choice. This article examines case law related to the issue of parental autonomy to determine whether the state, acting in the role of parens patriae, could use economic and social reasons to mandate the provision of cochlear implants for all eligible children. The author uses previous cases as a framework to develop an opinion on whether a constitutional protection for parents may exist.     

Spatial invariance of handwriting

Two aspects concerning the production of shapes in handwriting are distinguished in the present paper. The first aspect is indicated by thespatial variability of letters measured across replications. Spatial variability is assumed to reflect the basic spatial noise observed in everyday writing. The second aspect deals with the geometric characteristics of letter shapes, measured by the ratio of the vertical over the horizontal letter size (Y/X-ratio). The main question is whether the geometric characteristics and basic spatial noise originate from a common source. More specifically, we are interested in whether Y/X-ratio as well as spatial variability will alter across changed circumstances, or whether Y/X-ratio will alter without a change in spatial variability. Subjects wrote the simple letter sequencelelele in conditions with and without vision under three scaling conditions requirements (small, normal and large letter sizes). The main results were that geometric aspects of letters altered (Y/X-ratio) under no vision and under the scaling requirement to write in a small format. In contrast, shapes were produced with unchanged spatial variability in all conditions of vision and scaling requirements. The results suggest that alterations of geometric aspects of letters across changed circumstances do not necessarily involve an increase in spatial variability.     

Differences and similarities between violent offenders and sex offenders

OBJECTIVES: To investigate differences and similarities between violent offenders and two types of sex offenders, rapists and child molesters, in terms of their personality, the nature of the victim, the role of alcohol, and their confession to their crime. METHOD: Thirty-six adult sex offenders, 23 child molesters, and 32 violent offenders were compared on personality measures, their relationship with the victim, the presence of alcohol intoxication, their confession rate and retraction at trial, and the reasons they gave for having confessed to the police. RESULTS: Child molesters and adult sex offenders (rapists) were significantly more introverted than the violent offenders. The child molesters had higher social desirability scores than the other groups, they tended to assault relatives and friends, they were rarely intoxicated while committing the offense, and they had strong internal need to confess to the police. Rapists and violent offenders were more commonly intoxicated during the commission of the offense; the former tended to assault acquaintances, where violent offenders most commonly assaulted strangers. Exactly half of the rapists retracted their confession when the case went to trial; in contrast none of the other offenders retracted their confession. CONCLUSIONS: The results show that there are significant differences as well as similarities between the three groups of offenders, which have implications for assessment and treatment.     

Naming-speed processes, timing, and reading: a conceptual review

This article integrates the findings in the special issue with a comprehensive review of the evidence for seven central questions about the role of naming-speed deficits in developmental reading disabilities. Cross-sectional, longitudinal, and cross-linguistic research on naming-speed processes, timing processes, and reading is presented. An evolving model of visual naming illustrates areas of difference and areas of overlap between naming speed and phonology in their underlying requirements. Work in the cognitive neurosciences is used to explore two nonexclusive hypotheses about the putative links between naming speed and reading processes and about the sources of disruption that may cause subtypes of reading disabilities predicted by the double-deficit hypothesis. Finally, the implications of the work in this special issue for diagnosis and intervention are elaborated.     

POSTDICTION STUDY OF THE GRADUATE RECORD EXAMINATION AND EIGHT SEMESTERS OF COLLEGE GRADES1

Data from a postdictive study of the tests of the Graduate Record Examination and the eight semesters of undergraduate grade averages, each semester's average being computed independently of the rest, are presented. Postdictive validities of the aptitude portions of the GRE are essentially similar to predictive validities obtained earlier by the senior author. Both predictive and postdictive validity gradients over the eight semesters are relatively steep, with freshman grades having the highest correlations with the tests. The validity gradient for all advanced tests combined does not follow the pattern for the aptitude tests, but neither does it show the opposite gradient. Advanced test results are most highly correlated with sophomore grades, but the validity gradient over the eight semesters is relatively flat. A small scale extension of this research into post baccalaureate training indicated that senior grades were most predictive of graduate criteria, but a larger scale study is clearly called for. Possible implications for ability theory and for selection of graduate students are discussed.     

Use of grade-based norms versus age-based norms in psychoeducational assessment for a college population

Considerable discussion has occurred about the most appropriate methods for diagnosing learning disabilities (LD) in postsecondary students. Two of the many areas of controversy that have emerged include the appropriate diagnostic criteria to use and the appropriate referent group. A review of previous court cases demonstrates that the issue of whether to compare an individual to the general population or to a smaller referent population has not been adequately clarified. Furthermore, few empirical studies have examined the impact of choosing different referent groups on the likelihood that one will be diagnosed with LD. Therefore, this correlational study described the levels of agreement between three diagnostic models of LD, using both age- and grade-based norms to represent two referent groups for each of the three models. The sample included 155 postsecondary students referred for testing due to academic difficulties. The findings indicated that in two of the three models tested, comparing individuals to their grade-matched peers (i.e., using grade-based norms) resulted in more LD diagnoses than comparing individuals to their age-matched peers (i.e., age-based norms).