Computer methods and ecological validity in reading research

Computer-based procedures for obtaining word-by-word reading times are evaluated in terms of criteria for basic research and for ecologically valid research. Ecological validity can sometimes compromise experimental designs that should control extraneous variables or separate confounded factors. Two reading paradigms that were developed for basic research on linguistic coding mechanisms are also shown to meet many of the criteria for ecological validity.     

Reaction time measures of backward masking

We employed both simple and choice reaction time (RT) paradigms in which the subjects were required to respond to 3.0 cycles per degree (c/d) square-wave gratings presented to one eye, while checkerboard masks were presented at various stimulus-onset asynchronies to the other eye. No masking was evident using the simple RT paradigm, but with the choice RT task, checkerboard masks presented to the contralateral eye of three subjects resulted in substantial decreases in response speed when the test preceded the mask by stimulus-onset asynchronies of 25 to 75 ms. Masks that contained lower fundamental spatial frequencies (1.0 c/d) than the target were more effective than masks containing fundamental spatial frequencies (6.0 c/d) higher than the target, while masks that contained fundamental components identical to those in the target (3.0 c/d) produced maximum masking. The results offer support for the sustained-transient theory of visual processing and validate RT as a technique for examining spatio-temporal factors in masking.     

An entropy approach to the scaling of ordinal categorical data

This paper studies the problem of scaling ordinal categorical data observed over two or more sets of categories measuring a single characteristic. Scaling is obtained by solving a constrained entropy model which finds the most probable values of the scales given the data. A Kullback-Leibler statistic is generated which operationalizes a measure for the strength of consistency among the sets of categories. A variety of data of two and three sets of categories are analyzed using the entropy approach.This research was partially supported by the Air Force Office of Scientific Research under grant AFOSR 83-0234. The support by the Air Force through grant AFOSR-83-0234 is gratefully acknowledged. The comments of the editor and referees have been most helpful in improving the paper, and in bringing several additional references to our attention.     

The recoding of social orientations with ranking and pair comparison procedures

Ranking and pair comparison methods are proposed for the recording of individual social orientations. The experimental data were analysed with random utility models that were specially developed by the authors. The utility functions used contain almost all the social motives discussed in the literature as special cases. In order to classify the subjects into classes of similar social orientation, a procedure was proposed that was based on the particular utility function. The experiments were carried out with 144 subjects. The proposed recording methods and analysis procedures proved to be suitable. Results showed that not only simple social Orientation, such as individualism, competition, etc., could be observed in the subjects, but that orientations with more complex utility functions could also be found that have not previously been reported in the literature. The classification of the orientations using both methods showed a high level of agreement.     

The presence of a temporal discrimination in the conditioned emotional response with humans,

Six college students participated in matching-to-sample tasks. Conditioned emotional response (CER) training consisted of pairing a tone with a "painful" level of shock. Three of the subjects demonstrated response suppression, one subject showed facilitation, and two showed no change. Analysis of response rate during the tone interval indicated that, for those subjects who showed response suppression, the decrease in response rate was greatest immediately before onset of the unconditioned stimulus. This temporal discrimination was similar to that obtained with infrahumans.     

An evaluation of Unix in the psychology computer laboratory

Psychology users of the Unix operating system responded to questionnaire items concerning the use of Unix, the ease of learning and using Unix, and the value and quality of the system for their research needs. The data suggest that Unix is poor according to human-factors criteria, but good according to programming and systems criteria.     

Color preference for black and white by infants and young children

The purpose of this study was to determine whether a preference for the color white was present in infants and young children. A color preference test was administered to 160 subjects who ranged in age from 6 mo. to 4.5 yr. Data were obtained from a 120-item test in which 12 different pairs of toys were presented to each subject. The toys in each pair were identical except that one was black and the other was white. The toy the subject selected was considered the subject's preference and the color of that toy was recorded. Statistical analysis did not support existing literature, refuting the published idea that white preference is a general quality in all human beings.