The problems addressed, and solutions devised, by educational ethnographers in selection of and sampling from phenomena for internal representativeness external comparison are examined. The process of sampling is designated as a specialized form of the more general process of focusing and choosing in research, which is called selection. Common…

Researchers are often in a dilemma as to whether parametric or nonparametric procedures should be cited when assumptions of the parametric methods are thought to be violated. Therefore, the Kruskal-Wallis test and the ANOVA F-test were empirically compared in terms of probability of a Type I error and power under various patterns of mean…

This paper is based on a particulate pollutant system study to delineate the deficiencies in knowledge regarding the nature and magnitude of particulate pollutant emissions from stationary sources. Presented at the 12th Conference on Methods in Air Pollution and Industrial Hygiene Studies, University of Southern California, April, 1971, it focuses…

Since the development of causal path analysis by Wright, both the standardized and unstandardized procedures in path coefficient estimates have been advocated in the related literature, but the superiority of one technique over the other has not been demonstrated empirically or mathematically. In this study, the sampling properties of both…

A rederivation of Lord's formula for estimating variance in multiple matrix sampling is presented as well as the ways Cronbach's coefficient alpha and the Spearman-Brown prophecy formula are related in this context. (Author/JKS)

Authors present a formula for use when restrictions result from complex or unmeasured variables. (Authors/MB)

In a study of teacher role, the collection of data from a sample of teachers in the United States, Britain, Australia, and New Zealand is described, and the techniques used to analyze the data are discussed. (DB)

Explored possible response bias in a needs assessment survey for a hospice program. Results showed differences between the 22 caregivers who responded to the survey and the 38 who did not respond. Bias in the study may have eliminated clients with the most difficult experiences. (Author/JAC)

L-scaling is introduced as a technique for determining the weights in weighted averages or scaled scores for T joint observations on K variables. The technique is so named because of its formal resemblance to the Leontief matrix of mathematical economics. L-scaling is compared to several widely-used procedures for data reduction, and the…

Empirically determines if two approaches, i.e., individual predictor information versus group information, would yield different predictive results, and since the second approach involved the additional expense of grouping whether the prediction of criterion measures by individual data could be enhanced by the addition of group data. (Author/RC)

Three procedures for evaluating the sampling specificity of results are reviewed. These procedures are Tukey's jacknife technique, Efron's bootstrap technique, and cross-validation methods. The jacknife technique uses different subsamples derived from the original total data set to provide empirical estimates of the generalizability of effect…

Four potential biases incurred by using a sample of wives of male respondents as a sample of women for sex comparisons of the occupational attainment process were examined and empirically assessed. Using data from the Wisconsin longitudinal study of high school seniors, the extent and nature of two potential biases were considered: (1) a sampling…

Methods useful in identifying and assessing outcomes of relatively simple programs may not be practical or appropriate for complex programs and systems. Comparative case study methods are recommended for dealing with such global outcomes of planned organizational change. (Author)

Reports discrepancies between published outcomes from two international tests of science achievement: (1) Second International Assessment of Educational Progress (IAEP) administered in 1991; and (2) Third International Mathematics and Science Study (TIMSS) administered in 1995. States initial comparisons suggested outcome inconsistencies for 11…

Sources of population heterogeneity may or may not be observed. If the sources of heterogeneity are observed (e.g., gender), the sample can be split into groups and the data analyzed with methods for multiple groups. If the sources of population heterogeneity are unobserved, the data can be analyzed with latent class models. Factor mixture models…