@article {2697,
	title = {A Comparison of Constraint Programming and Mixed-Integer Programming for Automated Test-Form Generation},
	journal = {Journal of Educational Measurement},
	volume = {55},
	number = {4},
	year = {2018},
	pages = {435-456},
	abstract = {Abstract The final step of the typical process of developing educational and psychological tests is to place the selected test items in a formatted form. The step involves the grouping and ordering of the items to meet a variety of formatting constraints. As this activity tends to be time-intensive, the use of mixed-integer programming (MIP) has been proposed to automate it. The goal of this article is to show how constraint programming (CP) can be used as an alternative to automate test-form generation problems with a large variety of formatting constraints, and how it compares with MIP-based form generation as for its models, solutions, and running times. Two empirical examples are presented: (i) automated generation of a computerized fixed-form; and (ii) automated generation of shadow tests for multistage testing. Both examples show that CP works well with feasible solutions and running times likely to be better than that for MIP-based applications.},
	doi = {10.1111/jedm.12187},
	url = {https://onlinelibrary.wiley.com/doi/abs/10.1111/jedm.12187},
	author = {Li, Jie and van der Linden, Wim J.}
}
@article {2241,
	title = {Conditional Item-Exposure Control in Adaptive Testing Using Item-Ineligibility Probabilities},
	journal = {Journal of Educational and Behavioral Statistics},
	volume = {32},
	number = {4},
	year = {2007},
	pages = {398-418},
	abstract = {<p>Two conditional versions of the exposure-control method with item-ineligibility constraints for adaptive testing in van der Linden and Veldkamp (2004) are presented. The first version is for unconstrained item selection, the second for item selection with content constraints imposed by the shadow-test approach. In both versions, the exposure rates of the items are controlled using probabilities of item ineligibility given \&theta; that adapt the exposure rates automatically to a goal value for the items in the pool. In an extensive empirical study with an adaptive version of the Law School Admission Test, the authors show how the method can be used to drive conditional exposure rates below goal values as low as 0.025. Obviously, the price to be paid for minimal exposure rates is a decrease in the accuracy of the ability estimates. This trend is illustrated with empirical data.</p>
},
	doi = {10.3102/1076998606298044},
	url = {http://jeb.sagepub.com/cgi/content/abstract/32/4/398},
	author = {van der Linden, Wim J. and Veldkamp, Bernard P.}
}
@article {2237,
	title = {Constraining Item Exposure in Computerized Adaptive Testing With Shadow Tests},
	journal = {Journal of Educational and Behavioral Statistics},
	volume = {29},
	number = {3},
	year = {2004},
	pages = {273-291},
	abstract = {<p>Item-exposure control in computerized adaptive testing is implemented by imposing item-ineligibility constraints on the assembly process of the shadow tests. The method resembles Sympson and Hetter\&rsquo;s (1985) method of item-exposure control in that the decisions to impose the constraints are probabilistic. The method does not, however, require time-consuming simulation studies to set values for control parameters before the operational use of the test. Instead, it can set the probabilities of item ineligibility adaptively during the test using the actual item-exposure rates. An empirical study using an item pool from the Law School Admission Test showed that application of the method yielded perfect control of the item-exposure rates and had negligible impact on the bias and mean-squared error functions of the ability estimator.</p>
},
	doi = {10.3102/10769986029003273},
	url = {http://jeb.sagepub.com/cgi/content/abstract/29/3/273},
	author = {van der Linden, Wim J. and Veldkamp, Bernard P.}
}
