A correction of the standard F-ratio for unreliability of the dependent measure has recently been proposed by Winne; the rationale is analogous to that of correcting a correlation for attenuation. However, there are two problems associated with Winne's correction of which potential users should be aware. First, the corrected statistic, F*, has…

The known interval scale, referred to as the 7.8 scale, has been criticized as an invalid measuring instrument in the form of an attitude scale. It is the purpose of this paper to demonstrate that this scale can produce spuriously inflated correlation coefficients, high reliability, and false significance on statistical tests. The case will be…

Part and bi-partial canonical correlations were developed by extending the definitions of part and bi-partial correlation to sets of variates. These coefficients may be used to help researchers explore relationships which exist among several sets of normally distributed variates. (Author)

In this paper it is argued that the problem of construct validation in the construction of instruments and indicators is an important problem for educational researchers and practitioners; moreover, it is claimed that the popular notion of operational definition is a misleading idea which has obscured the problem of construct validity in…

An equation was derived to determine the relationship between the pooled within-subgroup r (correlation coefficient) and the r obtained from the total group data. It was, thus, possible to assess the amount of distortion introduced by pooling heterogeneous subgroups. As a basis for deciding whether to pool two subgroups in order to calculate a…

A computer-based learning simulation was developed at Florida State University which allows for high interactive responding via a time-sharing terminal for the purpose of demonstrating descriptive and inferential statistics. The statistical simulation (STATSIM) is comprised of four modules--chi square, t, z, and F distribution--and elucidates the…

Computational formulae for the following three tests of significance, useful in the interrupted time series design, are given: (1) a "t" test (Mood, 1950) for the significance of the first post-change observation from a value predicted by a linear fit of the pre-change observations; (2) an "F" test (Walker and Lev, 1953) of the…

The results of an extensive analysis of the statistical methodology employed by researchers whose manuscripts were published in the first twelve volumes of the "Educational Administration Quarterly" are reported. (Author)

A goodness of fit test presented by Andersen (EJ 143 939) is shown to be incorrect. The correct test is described and a re-analysis of Andersen's data is provided. (Author/CTM)

Graham Douglas' claims (TM 503 496) that the X2-test statistics of the paper, "Paired Comparisons with Individual Differences" (EJ 143 939), are incorrect are acknowledged to be justified (Author/CTM)

Reports a class exercise which requires students to recalculate the Chi-squares, t-tests, and one-way ANOVAs found in published psychological research articles. Describes students' reaction to the exercise and provides data on the 13% error rate they discovered. (Author/JDH)

Multiple regression analysis is frequently being employed in experimental and non-experimental research. However, when data include predictor variables that are correlated, some regression results can become difficult to interpret. This paper presents a study to provide a demonstration that structure coefficients may be useful in these cases.…

If the quantitative result of a study is observed only when the mean difference is statistically significant, the observed mean difference, variance, and effect size are biased estimators of corresponding population parameters. The exact distribution of sample effect size and the maximum likelihood estimator of effect size are derived. (Author/BW)

The Welch-James procedure may be used to test hypothesis on means, when independent samples from populations with heterogenous variances are available. Summation formulas for the Welch-James procedure are presented for the 2x2 design. Matrix formulas that permit routine application of the procedure to crossed factorial designs are presented.…

This report compares findings from the End of Training surveys administered to Participant Teachers (PTs) who took part in the Classic version of Intel Teach to the Future and who took part in the Expansion version of Intel Teach to the Future. Classic survey data were collected between March 2001 and July 2003. PT Expansion survey data were…