Understanding of immunological techniques such as the Enzyme Linked Immuno Sorbent Assay (ELISA) is an important part of instructional units in human health, developmental biology, microbiology, and biotechnology. This paper describes a simple ELISA exercise for undergraduate biology that effectively simulates the technique using a paper model.…

This digest discusses types of computer applications used in science assessment; underlying assumptions that guide their roles in assessment; and issues which relate to validity, gender equity, instructional delivery, mode of user interface, and responsibility to the public. Assessment applications for computers can be broadly classified into two…

An item response theory-based parametric procedure proposed by N. S. Raju, W. J. van der Linden, and P. F. Fleer (1995) known as differential functioning of items and tests (DFIT) can be used with unidimensional and multidimensional data with dichotomous or polytomous scoring. This study describes the polytomous DFIT framework and evaluates and…

In studies investigating the power of person-fit statistics it is often assumed that the item parameters that are used to calculate the statistics can be estimated in a sample without aberrant persons. However, in practical test applications calibration samples most likely will contain aberrant persons. In the present study, the influence of the…

Relating natural language to mathematical language is an important component of elementary mathematics education. This paper describes new steps toward a computerized database of addition and subtraction word problems that could provide teachers and students with access to critical natural language terms and expressions for mathematical…

Four papers from a project concerning information-processing characterizations of the knowledge and processes involved in design are presented. The project collected and analyzed verbal protocols from instructional designers, architects, and mechanical engineers. A framework was developed for characterizing the problem spaces of design that…

The zeitgeist for reform in education precipitated a number of changes in assessment. Among these are performance assessments, sometimes linked to "high stakes" accountability decisions. In some instances, the trustworthiness of these decisions is based on variance components and error variances derived through generalizability theory.…

When items are selected during a computerized adaptive test (CAT) solely with regard to their measurement properties, it is commonly found that certain items are administered to nearly every examinee, and that a small number of the available items will account for a large proportion of the item administrations. This presents a clear security risk…

Correlation coefficients are frequently reported in educational and psychological research. The robustness properties and optimality among practical approximations when phi does not equal 0 with moderate sample sizes are not well documented. Three major approximations and their variations are examined: (1) a normal approximation of Fisher's Z,…

The influence of sample size (N) and model parsimony on a set of 22 goodness of fit indices was investigated, including those typically used in confirmatory factor analysis and some recently developed indices. For sample data simulated from 2 known population data structures, values for 6 of 22 fit indices were reasonably independent of N and were…

The Mantel-Haenszel (MH) procedure has become one of the most popular procedures for detecting differential item functioning (DIF). One of the most troublesome criticisms of this procedure is that while detection rates for uniform DIF are very good, the procedure is not sensitive to non-uniform DIF. In this study, examinee responses were generated…

The assessment of dimensionality of data is important to item response theory (IRT) modelling and other multidimensional data analysis techniques. The fact that the parameters from the factor analysis formulation for dichotomous data can be expressed in terms of the parameters in the multidimensional IRT model suggests that the assessment of the…

An investigation of the effects of randomly missing data in two-predictor regression analyses is described. The differences in the effectiveness of five common treatments of missing data on estimates of R-squared values and each of the two standardized regression weights is also investigated. Bootstrap sample sizes of 50, 100, and 200 were drawn…

The extent to which properties of the ability scale and the form of the latent trait distribution influence the estimated item parameters of item response theory (IRT) was investigated using real and simulated data. Simulated data included 5,000 ability values randomly drawn from the standard normal distribution. Real data included the results for…

Suitable for secondary school students, the workbook provides flowcharting activities to help students understand the logical steps used in problem solving. Before applying the flowcharting procedures to mathematical problems, students are first introduced to familiar non-mathematical problems such as sharpening a pencil or eating peanuts. Section…