Six monographs on the Rasch model are summarized. The first gives a historical perspective on the application of the Rasch model in the Portland, Oregon, metropolitan area. The remaining papers summarize research on the Rasch model. The research in Monograph II lead to the conclusion that random samples are not needed to calibrate item levels in…

In a situation where the population distribution of latent trait scores can be estimated, the ordinary maximum likelihood estimator of latent trait scores may be improved upon by taking the estimated population distribution into account. In this paper empirical Bayes estimators are compared with the liklihood estimator for three samples of 300…

A study was conducted at Los Angeles Pierce College (LAPC) to test the relative reliability of small-sample telephone interviewing and large-sample mailings with postcard and telephone reminders for student follow-up. The study involved conducting a telephone survey of 245 former students who had enrolled at LAPC in four program areas, and a mail…

A comparison was made between four different scoring procedures for the 45-item Reading Comprehension subtest, Level I, of the Comprehensive Test of Basic Skills, Form S, for a sample of 1,000 third grade students. These students were selected to have been among those who omitted from 3 to 22 of the 45 items. Another representative sample of 1,300…

This report is based on the results of the Survey of Doctoral Scientists and Engineers and the Nonresponse Bias Survey published by the Commission on Human Resources of the National Research Council in 1975. Possible biases in estimates of variables are examined. Estimates based on data from the 1975 survey respondents, plus the nonresponse bias…

The effects of using different data analysis methods on estimates of treatment effects of educational programs were investigated. Various regression models, such as those recommended for Title I program evaluations, were studied. The first effect studied was the amount of bias that might be expected to occur in the various settings. Results…

Because latent trait models require that large numbers of items be calibrated or that testing of the same large group be repeated, item parameter estimates are often obtained by administering separate tests to different groups and "linking" the results to construct an adequate item pool. Four issues were studied, based upon the analysis…

The application of latent trait theory to classroom tests necessitates the use of small sample sizes for parameter estimation. Computer generated data were used to assess the accuracy of estimation of the slope and location parameters in the two parameter logistic model with fixed abilities and varying small sample sizes. The maximum likelihood…

A linear classification rule (used with equal covariance matrices) was contrasted with a quadratic rule (used with unequal covariance matrices) for accuracy of internal and external classification. The comparisons were made for seven situations which resulted from combining three data conditions (equal and unequal covariance matrices, minimal and…

The current manual NO (x) sampling and analysis method was evaluated. Improved time-integrated sampling and rapid analysis methods were developed. In the new method, the sample gas is drawn through a heated bed of uniquely active, crystalline, Pb02 where NO (x) is quantitatively absorbed. Nitrate ion is later extracted with water and the…

Achievement tests which are specifically linked to an instructional program and have been developed in relation to an objectives base and/or to an item generation rule are considered, as well as student response data. Three types of studies are outlined and the kind of procedures thought useful illustrated. As various methods for examining…

The intent of the study was to determine the extent to which test statistics computed by the unweighted means analysis are F-distributed. Applicability criteria were sought in terms of the number of factor levels and the degree to which cell frequencies differ. The unweighted means analysis, a frequently used approximate analysis, was contrasted…

Described and listed herein with concomitant sample input and output is the Fortran IV program which estimates parameters and standard errors of estimate per parameters for parameters estimated through multiple matrix sampling. The specific program is an improved and expanded version of an earlier version. (Author/BJG)

One solution to the problem of obtaining test scores in order to assess multiple outcomes of educational programs is a basically simple technique called matrix sampling. Matrix sampling is the estimation of total test score statistics by administering random subsets of test items to randomly selected students. This chapter lays out the specific…

An investigation was conducted of the characteristics of two estimation procedures and corresponding test statistics used in the analysis of completely randomized factorial experiments when observations are lost at random. For one estimator, contrast coefficients for cell means did not involve the cell frequencies. For the other, contrast…