The determination of hydrogen sulfide in effluents from coal-fired furnaces and incinerators is complicated by the presence of sulfur oxides (which form acids). Organic compounds also may interfere with or prevent the formation of the cadmium sulfide precipitate or give false positive results because of reaction with iodine. The report presents a…

Distributional characteristics of the measure of sampling adequacy (MSA) were investigated in sample correlation matrices generated from multivariate normal populations with covariance matrix equal to the identity. Systematic variation of sample size and number of variables resulted in minimal fluctuation of the overall MSA from .50. (Author/RC)

Compares the harmonic mean and Kramer unequal group forms of the Tukey test for various: (a) degrees of disparate group sizes, (b) numbers of groups, and (c) nominal significant levels. (RC)

Describes a sampling demonstration, using random numbers generated on a microcomputer, that helps to make the central limit theorem concrete and understandable. (Author/JDH)

Normative sampling procedures were used to determine behavioral compatibility of two disabled students considered academically ready for placement in a regular English class. The procedure compared rate of students' disruptive behavior to range and mean of disruptive behavior of the class considered for placement. (Author/CL)

While violation of the homogeneity of variance assumption has received considerable attention, violation of the assumption of normally distributed data has not received as much attention. As a result, researchers may have the mistaken impression that as long as the assumptions of independence of observations and homogeneity of variance are…

A revised version of Kaiser's Measure of Sampling Adequacy for factor-analytic data matrices is presented. (Author)

Presents a formula for the determination of sample size in survey research and methods for its manipulation in relation to (1) the nature of the problem; (2) the homogeneity of the population; (3) the desired degree of precision; and (4) allowable costs. (Journal availability: Department of Adult Education, Kansas State University, Manhattan, KS…

The work-sampling approach derives a composite overall picture of how an individual allocates time by taking a sufficiently large number of spot observations of activity at random intervals. (For availability, see EA 507 433.) (Author)

The Box-Scheffe and Z-Variance tests for homogeneity of variance are discussed and compared in light of a previous comparison in the literature. Alternative statistics to these tests are discussed and a table comparing the power of the tests is provided. (JKS)

Bechhofer's procedure for selecting the population with the largest mean from among several populations with known variances is discussed as it applies to the problem of selecting the bivariate normal population with the largest correlation coefficient. Tables of appropriate sample sizes are provided and an example is discussed. (Author/JKS)

Various types of finite mixtures of confirmatory factor analysis models are proposed for handling data heterogeneity. Proposed classes of mixture models differ in their unique representations of data heterogeneity, and three sampling schemes for these mixtures are distinguished. Advantages of the Approximate Scoring method are outlined. (SLD)