Test Design and Speededness

A critical component of test speededness is the distribution of the test taker's total time on the test. A simple set of constraints on the item parameters in the lognormal model for response times is derived that can be used to control the distribution when assembling a new test form. As the constraints are linear in the item parameters, they can easily be included in a mixed integer programming model for test assembly. The use of the constraints is demonstrated for the problems of assembling a new test form to be equally speeded as a reference form, test assembly in which the impact of a change in the content specifications on speededness is to be neutralized, and the assembly of test forms with a revised level of speededness.