AN EXAMINATION OF THE ASSUMPTION THAT THE EQUATING OF PARALLEL FORMS IS POPULATION-INDEPENDENT

Linear conversions were developed relating scores on two recent forms of the homogeneous GRE Quantitative Test (GRE-Q) and the specially constituted heterogeneous GRE Verbal-plus-Quantitative Test (GRE-V+Q), using randomly equivalent groups of about 13, 000 taking each form. Specially defined homogeneous subpopulations were then identified, and conversions between scores on the two forms were again calculated, this time based on l000-case samples drawn at random from the subpopulations. Finally, in order to develop empirical measures of equating error, I00 samples of 1, 000 cases each were drawn at random from the two total groups and used to calculate 100 conversions between scores on the two forms. The conversions based on the specially selected subpopulations were then compared with the total-group conversions and evaluated in terms of the empirical standard errors. The results showed that the conversions for the subpopulations agreed with the total-group conversion quite satisfactorily for the GRE-Q and almost as well for the GRE-V+Q. It was concluded that the data clearly support the assumption of population independence for homogeneous tests, but not quite so clearly for heterogeneous tests.     

The US-preexposure effect in honeybees

Signaled avoidance was studied in individual honeybees that visited the laboratory regularly to take sucrose solution from a target set on the sill of an open window. During feeding, substrate vibration or airstream was used to signal a brief shock that could be avoided by breaking off contact with the food for a few seconds. Aversive conditioning of the context was measured in terms of return time (the time between successive visits). In Experiment 1, experience with unsignaled shock was found to lengthen return time—which experience with signaled shock did not—and to impair performance in subsequent avoidance training with signaled shock (the US-preexposure effect). In Experiment 2, experience with unsignaled shock given after signaled avoidance training lengthened return time but had no effect on response to the signal in a subsequent extinction test. These results closely resemble the results obtained in analogous experiments with vertebrates.     

Video Presentations that have to Teach

To be successful, an instructional video presentation needs to be effective, valued, liked and efficient, and educationalists and designers should strive (explicitly and implicitly) to satisfy these criteria. In the interests of optimum teaching effect, a didactical distinction is recommended between video presentations that have to ‘instruct’, ‘explain’, ‘tell’ and ‘let encounter’. A schema or frame of reference is proposed, the use of which (it is claimed) can help to optimise communication between video producer, teacher and instructional designer     

Concurrent validity of the test of nonverbal intelligence with learning disabled children

Results of the TONI, WISC-R, and WRAT were compared for a sample of 66 learning disabled children: 51 males (32 white, 19 black) and 15 females (9 white, 6 black) whose mean age was 9–5 (SD = 1–10). The mean score of the TONI was significantly different from the Performance IQ. Nonsignificant differences were found between the TONI and Full Scale IQ and between the TONI and Verbal IQ. Correlation coefficients between the TONI and WISC-R ranged from a low of .35 for the Verbal IQ to .44 for both the Full Scale and Performance IQs. The correlation coefficients between the TONI and standard scores of the WRAT were .38, .27, and .23, for Reading, Spelling, and Arithmetic, respectively. Implications of these findings are discussed.     

Are mastery learning strategies beneficial for developing problem solving skills?

The purpose of the present study was to investigate instructional methods appropriate for developing problem solving skills (PSS) in a paramedical course. Three instructional methods were compared: Frontal Lecture Strategies (FLS), Mastery Learning Strategies (MLS) and Experiential Mastery Learning Strategies (EMLS) in which feedback corrective procedures were embedded within experiential learning situations. Results showed that FLS produced the highest scores on Lower Mental Process subtest while EMLS yielded the highest scores on all measures of problem solving skills. Several implications of this study for future research are suggested and discussed.     

Do infants see emotional expressions in static faces?

To determine whether young infants discriminate photographs of different emotions on an affect-relevant basis or on the basis of isolated features unrelated to emotion, groups of 17-, 23-, and 29-week-olds were habituated to slides of 8 women posing either Toothy Angry, Nontoothy Angry, or Nontoothy Smiling facial expressions and were then shown 2 new women in the familiarized expression and in a novel Toothy Smiling expression. At all 3 ages, recovery to the novel Toothy Smiling faces occurred only after habituation to Nontoothy faces (whether smiling or angry), not after habituation to Toothy Angry faces, indicating that infants had been responsive to nonspecific features of the photographs (presence or absence of bared teeth) rather than to affectively relevant configurations of features. In a second experiment, 2 older age groups (35 and 41 weeks) also proved to be insensitive to affect-related aspects of still faces, though more so for angry than for happy expressions. It is suggested that the young infant's difficulty in extracting emotional information from static stimuli may be attributable to the absence of the critical invariants (dynamic, multimodally specified) that characterize naturalistic expressions of emotion.     

The rhythmic structure of mother-infant interaction in term and preterm infants

The purpose of this study was to quantify social interaction rhythms in 3- and 5-month-old term and preterm infants and their mothers. Infant-mother dyads were videotaped in a 3-min face-to-face paradigm. For each second of the interaction, separate scores were assigned to infant and mother indicating levels of affective involvement, creating 2 180-sec time series. Spectral and cross-spectral techniques were used to quantify periodicities in each member of the dyad and to estimate the synchrony or coherence of interactional rhythms between each infant and mother. Results showed the existence of periodicities in the behavior of each infant and mother at 3 and 5 months, with most subjects showing spectral peaks between .022 and .10 Hz. Increases from 3 to 5 months in behavioral periodicities were found for infants and mothers as well as for the coherence between infant-mother dyads. Term dyads showed higher coherence than preterm dyads at both 3 and 5 months. Term infants more often led the interaction at both ages. These results were taken as evidence that behavioral periodicities, which may be biologically based, underlie early mother-infant interaction and provide a temporal structure for the organization of cognitive and affective experience. Differences in synchrony between term and preterm infants may explain later reported differences in language between these groups.     

Evidence for confounding in computer-based instruction studies: Analyzing the meta-analyses

A thirty percent sample of the computer-based instruction (CBI) studies meta-analyzed by Kulik et al was examined for evidence of confounding. The purpose of the analysis was to explore the validity of competing claims about the contribution of the computer to measured achievement gains found in CBI studies. Some of these claims propose that CBI effects are overestimated and others argue that CBI effects are underestimated. The result of the analysis strongly suggests that achievement gains found in these CBI studies are overestimated and are actually due to the uncontrolled but robust instructional methods embedded in CBI treatments. It is argued that these methods may be delivered by other media with achievement gains comparable to those reported for computers. Construct validity cautions are offered for those who wish to use meta-analytic results as evidence for implementing CBI in schools and for the design of future CBI research.