Application of the Rasch model to measuring the impact of scientific journals

This paper focuses on a fresh and fair way to determine a ranking of science journals according to the ''number of citations-to and articles published,'' data used by SCI Journal Citation Reports of ISI to determine journal ranking by ''impact factor.'' Impact is considered a latent variable defined by a set of items (citations and articles published). The theoretical background is Item Response Theory, which suggests that, if we can understand 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 most common formulation of that theory. This technique is here applied to the citations and articles published of 62 medical journals (objects) to provide a Rasch measure for these journals which is compared with the current ''impact factor'' computation.