Inferability of Unbounded Unions of Certain Closed Set Systems

摘要

In this article, we study inferability from positive data for the unbounded union of certain class of languages. In order to show inferability, we put an emphasis on a characteristic set of a given language. We consider a class of closed set systems such that there exists an algorithm for generating a characteristic set consisting of one element. Two concrete examples of closed set systems with such algorithms are given. Furthermore, we consider applications of these examples to the study of transaction databases.