This study assessed the effects of small-group tutoring with and without validated classroom instruction on at-risk students' math problem solving. Stratifying within schools, 119 3rd-grade classes were randomly assigned to conventional or validated problem-solving instruction (Hot Math, schema-broadening instruction). Students identified as at…

The ECTS grade transfer scale is an interface grade scale to help European universities, students and employers to understand the level of student achievement. Hence, the ECTS scale can be seen as an interface, transforming local scales to a common system where A-E denote passing grades. By definition, ECTS should distribute the passing students…

Loglinear and logit models that have been suggested for studying differential item functioning (DIF) are reviewed, and loglinear formulations of the logit models are given. A polynomial loglinear model for assessing DIF is introduced that incorporates scores on the matching variable and item responses. The polynomial loglinear model contains far…

This paper addresses issues of vertical equating for the Arkansas Comprehensive Testing, Assessment and Accountability Program (ACTAAP) assessments as they relate to school accountability and determination of Adequate Yearly Progress (AYP) as required by the recent federal legislation, the No Child Left Behind Act. The paper first provides a brief…

Two traditional equating schemes and seven item response theory equating schemes were compared. Data used came from the 1978 equating project of the Iowa Tests of Educational Development. The study entailed both the equating of forms of similar difficulty and the equating of levels of differing difficulty. (Arthor/RL)

Determining whether score distributions differ on two or more test forms administered to samples of examinees from a single population is explored using three statistical tests using loglinear models. Examples are presented of applying tests of distribution differences to decide if equating is needed for alternative forms of a test. (SLD)

Scales defined by most item response theory (IRT) models are truly invariant with respect to certain linear transformations of parameters. The problem is to find the proper transformation to place calibrations on a common scale. This paper explores issues of extending and adapting unidimensional linking procedures to multidimensional IRT models.…

Simulated items from two test forms using joint maximum likelihood estimation (JMLE) and marginal maximum likelihood estimation (MML) in the vertical equating situation (using an anchor test) when data were nonrandomly missing. Under MML, when the different ability parameters of students were not taken into account, the item difficulty parameters…

Conducted a simulation study of separate versus concurrent item parameter estimation in common item equating using simulation data from a test with 60 dichotomous items and considering: (1) estimation program; (2) sample size per form; (3) number of common items; and (4) equivalent versus nonequivalent groups. Results are not decisive enough to…

A general delta method is described for computing the standard error (SE) of a chain of linear equations. The general delta method derives the SEs directly from the moments of the score distributions obtained in the equating chain. Computer simulations demonstrate the method. (SLD)

The effects of different degrees of smoothing on results of equipercentile equating in random groups design using a postsmoothing method based on cubic splines were investigated, and a computer-based procedure was introduced for selecting a desirable degree of smoothing. Results suggest that no particular degree of smoothing was always optimal.…

Studied whether circular equating could provide an adequate measure of various types of equating error when applied to different equating methods under different equating designs. Analyses and simluations show that circular equating is generally invalid as a criterion to evaluate the adequacy of equating. (SLD)

VALEURTECH is a pilot project under the European Commission's Leonardo II programme. It includes 35 partners from higher education institutions and professional organizations in eight European countries and has the major objectives: of (a) setting up a homogeneous "labelling" process, such as a diploma supplement, based on a common…

The discussion here covers five articles that are linked in the sense that they all treat population invariance. This discussion of population invariance is a somewhat broader treatment of the subject than simply a discussion of these five articles. In particular, occasional reference is made to publications other than those in this issue. The…

A sequence of simulations was carried out to aid in the diagnosis and interpretation of equating differences found between random and matched (nonrandom) samples for four commonly used equating procedures: (1) Tucker linear observed-score equating; (2) Levine equally reliable linear observed-score equating; (3) equipercentile curvilinear…