Gender differences in geographical knowledge

In five experiments involving more than 1800 undergraduate students, males more accurately located places on maps of the United States or its various regions than did females. These gender differences could not be attributed to education, travel history, desire to travel, or in the amount of incidental exposure to several potential sources of geographic information in everyday life. Males performed more accurately than females on measures of egocentric and allocentric spatial orientation, but performance on these tasks was only weakly predictive of accuracy on tests of geographical knowledge. Since males and females learned the locations of places on an unfamiliar map at similar rates, regardless of whether such learning occurred under intentional or incidental instructions, gender differences in geographical knowledge cannot be attributed to differences in capacity to learn place locations on maps. An attentional hypothesis is proposed to account for the more accurate performance of males on tests of geographical knowledge.     

Shift in stimulus range and the exponent of the power function for loudness

The exponent of the power function for loudness was tracked over the course of 60 trials with one stimulus range and compared to the exponent over the course of 60 subsequent trials with a different stimulus range. Three stimulus sets were used: (1) weak, a short range of relatively soft tones (45-55 dBA); (2) strong, a short range of relatively loud tones (64-74 dBA); and (3) complete, a longer range of soft to loud tones (40-90 dBA). All pairs of stimulus sets were tested, together with three control conditions in which no shift in range occurred. Ten subjects were run in each of the nine groups. For preshift trials, the mean exponent was lowest for the strong stimulus series, highest for the weak series, and at an intermediate value for the complete series. These differences were all significant. Following a shift in stimulus range, the weak series still yielded the highest exponent, but the exponents were not reliably different for the complete and strong series. Postshift exponents also depended significantly on the preshift range experienced by the subjects. These effects were not confined to the period immediately following the shift in range, but persisted for up to 60 trials.     

Electrodermal nonresponding, premorbid adjustment, and symptomatology as predictors of long-term social functioning in schizophrenics

The hypothesis that electrodermal nonresponsiveness to orienting stimuli delineates a core group of "Kraepelinian" type schizophrenics was tested by following up social functioning outcome over a 2-year period in 37 schizophrenics. Good social functioning outcome required both some self-supporting ability in the job market and a minimal social life. The prior assessments included monitoring of electrodermal responses to a series of moderately intense tones, ratings of reported and observed symptoms during an interview, and ratings of premorbid adjustment on the basis of an interview with a close relative. Electrodermal nonresponding, poor premorbid adjustment, and negative symptomatology predicted poor social functioning during the second follow-up year, but the relationship to nonresponding pertained exclusively to a group of 15 first-episode patients. Discriminant analysis showed that electrodermal nonresponding and symptoms were the only independent predictors of outcome.     

Additive hypotheses of the effect of head and eye movement on dark convergence

Dark vergence depends on the vertical direction of gaze; it decreases with raised gaze and increases with lowered gaze. The vertical direction of gaze can be varied by means or raising or lowering the eyes or by way of tilting the head forward or backward. The effects of both manipulations on dark vergence are different. According to Heuer (1988) the effects of head tilt and eye inclination on dark vergence are almost, but not exactly, additive. In Exp. 1 the hypothesis of additive effects of gaze direction and eye inclination was tested and could not be rejected. The two additive hypotheses (head tilt and eye inclination vs. gaze inclination and eye inclination) result in different predictions for dark vergence with "compensatory" head and eye inclinations, which leave the direction of gaze in space invariant. In Exp. 2 it was shown that predictions from both hypotheses deviated from the observed values of dark vergence. Thus none of the two additive hypotheses provides exact predictions of dark vergence for all possible combinations of head tilt and eye inclination. For practical purposes the approximation might be sufficient. In particular, although mean dark vergence cannot be predicted exactly, individual differences can be predicted quite accurately.     

Automaticity and interference in bilinguals

Summary In an experimental study with 40 English-German and 40 German-Swedish bilingual high school students, automaticity and interference were analyzed on the basis of Shiffrin and Schneider's theory of controlled and automatic processing. Confirming the assumptions inferred from the theory, dominant bilinguals reacted significantly faster to pictured objects in their dominant language than did balanced bilinguals in either of their two languages. Interaction effects with frequency indicated less experience with rare words in the balanced groups. Matched on the basis of reaction time scores, the balanced groups continued to show a higher error rate in recall, but not in recognition when compared with the dominant groups. It was concluded that training alone could not account for the differences in recall. A congenitally determined mental speed factor was suggested for which the theory makes no direct commitment. The strong interrelation between automaticity and interference was shown; their significance for bilinguals in highly speeded and unstructured tasks was also shown. The results reveal high cross-cultural consistency.An earlier version of this paper was presented at the 3rd Nordic Symposium on Bilingualism, held in Umea, Sweden, June 4 to 5, 1980     

Factor analysis by instrumental variables methods

Three alternative estimation procedures for factor analysis based on the instrumental variables method are presented. These procedures are justified by the method of least squares. Formulas for asymptotic standard errors of factor loadings are derived. The procedures are empirically compared to the method of maximum likelihood. The conclusion, based on the data used in this study, is that two of the procedures seem to work well.     

Location vs. frequency of pure tones as a basis of fast discrimination

There are ample data suggesting that a spatial difference between two competing auditory messages provides a better basis for selective attention and listening than other differences. The present experiments show that the spatial difference (left vs. right ear) between two auditory inputs leads to their faster discrimination than even large differences in frequency (in the same ear). These results might explain the afore-mentioned privileged status of the spatial dimension as a basis of selective attention: spatial differences lead in faster identification of relevant or attended input than differences in other dimensions.