Summary Employing a Wald confidence interval to test hypotheses about population proportions could lead to an increase in Type I or Type II errors unless the hypothesized value, p0, is used in computing its standard error rather than the sample proportion. Whereas the Wald confidence interval to estimate a population proportion uses the sample…

In this paper, I propose to demonstrate a means of error estimation preprocessing in the assembly of overlapping aerial image mosaics. The mosaic program automatically assembles several hundred aerial images from a data set by aligning them, via image registration using a pattern search method, onto a GIS grid. The method presented first locates…

Critics of standardized testing have recommended replacing standardized tests with more authentic assessment measures, such as classroom assignments, projects, or portfolios rated by a panel of raters using common rubrics. Little research has examined the consistency of scores across multiple authentic assignments or the implications of this…

In this policy brief, the author explores the problems with attainment measures when it comes to evaluating performance at the school level, and explores the best uses of value-added measures. These value-added measures, the author writes, are useful for sorting out-of-school influences from school influences or from teacher performance, giving…

The goals of this article are twofold: (a) briefly highlight the merits of residual centering for representing interaction and powered terms in standard regression contexts (e.g., Lance, 1988), and (b) extend the residual centering procedure to represent latent variable interactions. The proposed method for representing latent variable…

When treatments are administered in groups, clients interact in ways that lead to violations of a key assumption of most statistical analyses-the assumption of independence of observations. The resulting dependencies, when not properly accounted for, can increase Type I errors dramatically. Of the 33 studies of group-administered treatment on the…

To deal with nonnormal and heterogeneous data for the one-way fixed effect analysis of variance model, the authors adopted a trimmed means method in conjunction with Hall's invertible transformation into a heteroscedastic test statistic (Alexander-Govern test or Welch test). The results of simulation experiments showed that the proposed technique…

Eight independent variables (differential item functioning [DIF] detection method, purification procedure, item response model, mean latent trait difference between groups, test length, DIF pattern, magnitude of DIF, and percentage of DIF items) were manipulated, and two dependent variables (Type I error and power) were assessed through…

The quality of educational data in Nepal was evaluated by investigating three questions: (1) the extent of reporting error in national education data; (2) accuracy of error estimation; and (3) levels at which error is introduced. Evidence suggests that data may be more accurate than decision makers suppose. (SLD)