Linear programing was used to select items from item pools (N=1,500) based on one-, two-, and three-parameter models so that a target test information function (TTIF) was reached. Focus was on the distributional characteristics of selected items. The linear-programing approach focuses on the worst feature of the TTIF. (TJH)

A method is described for simultaneous test construction using the Operations Research technique zero-one programming. The model for zero-one programming consists of two parts. The first contains the objective function that describes the aspect to be optimized. The second part contains the constraints under which the objective function should be…

The distribution of a certain item response theory (IRT) based person fit index to identify systematic types of aberrance is discussed. For the Rasch model, it is proved that: (1) the joint distribution of subtest-residuals (the components of the index) is asymptotically multivariate normal; and (2) the distribution of the index is asymptotically…

This brief overview notes that an adaptive test differs from standardized achievement tests in that it does not consist of a certain set of items that are administered to a group of examinees. Instead, the test is individualized for each examinee. The items administered to the examinee are selected from a large pool of items on the basis of the…

Computer-adaptive testing (CAT) allows improved security, greater scoring accuracy, shorter testing periods, quicker availability of results, and reduced guessing and other undesirable test behavior. Simple approaches can be applied by the classroom teacher, or other content specialist, who possesses simple computer equipment and elementary…

The construction of parallel tests from item response theory (IRT) based item banks is discussed. Tests are considered parallel whenever their information functions are identical. After the methods for constructing parallel tests are considered, the computational complexity of 0-1 linear programming and the heuristic procedure applied are…

A procedure for the sequential optimization of the calibration of an item bank is given. The procedure is based on an empirical Bayes approach to a reformulation of the Rasch model as a model for paired comparisons between the difficulties of test items in which ties are allowed to occur. First, it is indicated how a paired-comparisons design…

Nine methods for automated test construction are described. All are based on the concepts of information from item response theory. Two general kinds of methods for the construction of parallel tests are presented: (1) sequential test design; and (2) simultaneous test design. Sequential design implies that the tests are constructed one after the…

A new test construction method based on integer linear programming is described. This method selects optimal tests in small amounts of computer time. The new method, called the Cluster-Based Method, assumes that the items in the bank have been grouped according to their item information curves so that items within a group, or cluster, are…

The central idea in building and maintaining an item bank is to calibrate all the items onto a "common variable." The arithmetic involved in the calibration process is presented. It is recommended that an analysis of fit be done in every application to verify that the estimates of item difficulties are in fact sample-free. These…

Differential drift of item location parameters over a 10-year period is demonstrated in data from the College Board Physics Achievement Test. Item content and secondary school curricula shifts are associated with drift. Statistical procedures for detecting item parameter drift in item pools for long-term testing programs are proposed. (TJH)

This report describes a procedure that promises to improve the stability, accuracy, and efficiency of the employment of latent trait models and an application of the procedure to the Rasch model. Data were collected from the Portland Public Schools Level Tests administered to 25,740 students. Since each of the 173 items (chosen from the total…

Although two-stage testing is not the most efficient form of adaptive testing, it has some advantages. In this paper, linear programming models are given for the construction of two-stage tests. In these models, practical constraints with respect to, among other things, test composition, administration time, and inter-item dependencies play an…

A "maximin" model for item response theory based test design is proposed. In this model only the relative shape of the target test information function is specified. It serves as a constraint subject to which a linear programming algorithm maximizes the information in the test. In the practice of test construction there may be several…

Two iterative procedures for constructing Rasch scales are presented. A log-likelihood ratio test based on a quasi-loglinear formulation of the Rasch model is given by which one item at a time can be deleted from or added to an initial item set. In the so-called "top-down" algorithm, items are stepwise deleted from a relatively large…