Browsing by Author "Alexander, Ralph A."

Now showing 1 - 6 of 6
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    Correcting for range restriction when the population variance is unknown
    (1984) Alexander, Ralph A.; Alliger, George M.; Hanges, Paul J.
    Correction of correlations diminished by range restriction is a commonly suggested psychometric technique. Such corrections may be appropriate in applied settings, such as educational or personnel selection, or in more theoretical applications, such as meta-analysis. However, an important limitation on the practice of range restriction corrections exists-an estimate of the unrestricted population variance is required. This article outlines and examines the accuracy of a method for estimating the unrestricted variance of a variable from the restricted sample itself. This method is based on the observation that it is possible to table a function of the truncated normal distribution that will allow the extent or point of truncation to be estimated (Cohen, 1959). The correlation of the truncated variable with other variables may then be corrected by standard restriction of range formulas. The method also allows for correction of the mean of the restricted variable.
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    Correcting for restriction of range in both X and Y when the unrestricted variances are unknown
    (1985) Alexander, Ralph A.; Hanges, Paul J.; Alliger, George M.
    Correction of correlation coefficients that have arisen from range restricted populations is commonly suggested and practiced in research on testing and measurement. Until recently, that research has operated under two important limitations. First, the majority of the research has dealt with range restriction on one variable only, and second, the correction formulas have assumed that the variance of the variable(s) in the unrestricted population was known. This article presents a method for estimating such corrections from the data in the restricted sample and applies the method to a recently developed approximation for restriction on both and Y. The procedure is evaluated and found to produce sufficiently accurate results to be useful in many practical range restriction settings.
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    Correction for restriction of range when both X and Y are truncated
    (1984) Alexander, Ralph A.; Carson, Kenneth P.; Alliger, George M.; Barrett, Gerald V.
    The effect of range restriction on one variable in a bivariate normal distribution on the X-Y correlation and the problem of estimating unrestricted from restricted correlations has been widely studied for more than half a century. The behavior of correction formulas under truncation of both X and Y, however, remains largely unresearched. The performance of the correction formula for unidimensional truncation (Thorndike, 1947, Case 2) and an approximation procedure for correcting for bidimensional truncation proposed by Wells and Fruchter (1970) were investigated. The Thorndike correction formula undercorrects in most circumstances. The Wells and Fruchter procedure performs quite well under most conditions but often results in a slight overcorrection. The performance of the Wells and Fruchter and Thorndike formulas are also compared under truncation on X or Y alone. In these circumstances the Wells and Fruchter correction is either equal or markedly superior to the traditional correction. Based on overall performance in recapturing the unbiased population values under both unidimensional and bidimensional truncation, the Wells and Fruchter correction is recommended as the preferred procedure in many practical settings.
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    Designing a measure of visual selective attention to assess individual differences in information processing
    (1981) Avolio, Bruce J.; Alexander, Ralph A.; Barrett, Gerald V.; Sterns, Harvey L.
    A new method for determining individual differences in information processing was developed and illustrated. The measure, Visual Selective Attention, was constructed according to the parameters and specifications of a standardized measure of auditory selective attention. Emphasis was placed upon establishing the relationship of this new measure with traditional measures of information processing (i.e., perceptual style and selective attention). The results provided initial evidence for the reliability and validity of the new measure. Applications for Visual Selective Attention and interpretation of the findings are discussed in view of the current state of the information-processing literature. Implications for additional research focus upon the practical applications of the new measure.
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    The development and application of a computerized information-processing test battery
    (1982) Barrett, Gerald V.; Alexander, Ralph A.; Doverspike, Dennis; Cellar, Douglas; Thomas, Jay C.
    To bridge the gap between computerized testing and information-processing-based measurement, a battery of computerized information-processing based ability and preference measures was developed. The information-processing and preference measures and a battery of paper-and-pencil tests were administered to 64 college students. Although the internal-consistency reliabilities of the computerized information-processing measures were adequate, test-retest reliabilities were lower than desirable for ability measures. The computerized information-processing measures possessed moderate convergent validity but had low correlations with traditional paper-and-pencil measures. Of the computerized preference measures, the most promising results were obtained with the Stimulus Pace measure. A major problem with the use of the computerized information-processing measures in applied settings would be administration time, as the battery took approximately 4 hours. In addition, problems with the stability of results over time and substantial practice effects suggest that even longer testing sessions would be required to obtain reliable measures. Although information-processing measures of short-term memory have, at best, low correlations with traditional intelligence tests, their ability to predict real-world tasks has yet to be sufficiently researched.
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    Scoring the biographical information blank: A comparison of three weighting techniques
    (1983) Telenson, Paul A.; Alexander, Ralph A.; Barrett, Gerald V.
    This study compared three techniques for scoring a biographical information blank (horizontal percent method, vertical percent method, and rare response weighting) against various criteria for field sales representatives. The comparisons were cross-validated over five consecutive time periods. The results showed that the rare weighting technique significantly predicted criterion group membership better than chance. Neither the horizontal nor vertical percent methods predicted criterion group membership better than chance. Based on predictive efficiency, the rare weighting technique was found to be superior to the other two techniques.