Statistics for measuring the efficiency of electronic information retrieval

As electronic information searching with different software strategies and interactive systems becomes the only way to access desired holdings, the need to measure the efficiency of individual search strategies becomes critical to the research process that drives the choice of systems and instruction. Formal experimental research depends on the choice and use of an appropriate statistical technique. The relationship between two dichotomously categorized variables distributed on an underlying continuous distribution is a tetrachoric correlation. The use of the tetrachoric correlation for experimental research and hypothesis testing of the efficiency of computerized information searching is described and illustrated.