The Statistical Verisimilitude of Qualitative Theories

In this paper we will deal with the problem of the verisimilitude of qualitative theories stated in first order languages with two or more families of predicates (Qtheories). In particular, we will explicate the notion of Q-theory and define suitable measures of the qualitative verisimilitude of Q-theories. Afterwards, we will introduce appropriate measures for the statistical verisimilitude of Q-theories. This will allow us to show that Q-theories can be used to describe the statistical structure of cross classified populations, and that their adequacy in this task can be evaluated by measuring their statistical verisimilitude.