A Case Where It Is Better to have an Unstandardized measure of the Right Construct than a Standardized Measure of a Related One: Application to Coding Interviews Within a Course in SAS Programming

Abstract

Interview-based examinations provide richer data than formats such as multiple choice and short answer, albeit at the cost of being less standardized. This describes administering a coding interview as the final examination in a class on SAS programming, plus primarily qualitative reflections. We conclude that when the goal is to assess facility with programming an interview-based examination should come into especial consideration. We argue that a coding interview measures the right thing, namely how well the student designs and writes SAS programs – which in turn depends on factors such as general programming literacy, critical SAS-specific knowledge, ability to design SAS programs, and the ability to engage in problem solving as part of the process of program development -- rather than something that is merely correlated with this core construct, as would be the case for the objective questions that are included within typical certification tests. In doing so it is not completely standardized, but sufficiently so. This examination format more closely matches how students engage in SAS programming in actual practice: for example, by incorporating web searching. Moreover, it has the innovative and desirable property of embedding instruction in addition to evaluation. Coding interviews are a time-intensive form of evaluation, but much more is learned about student performance, there is an opportunity to teach as you go, and the time is well spent.