THE RASCH MODEL - MEASURING THE IMPACT OF SCIENTIFIC JOURNALS - ANALYTICAL-CHEMISTRY

This article focuses on a fresh way to determine a ranking of science journals according to the ''number of citations-to and items-published ,'' data used by SCI JCR of ISI to determine journal ranking by ''impa ct factor.'' This is the first application of latent traits theory to bibliometrics. ''Impact'' is considered a latent variable defined by a set of items (or indicators), citations, and sources. The theoretical background is Item Response Theory, which suggests that, if we can un derstand how each item in a set of items operates with an object, then we can estimate a measure for the object. The Rasch model is the comm onest formulation of that theory. This technique is here applied to th e citations and sources of 43 Analytical Chemistry journals (objects) to provide a Rasch measure for these journals which is compared with t he current ''impact factor'' computation.