Feature extraction of the “English Proficiency Test” conducted by the National Association of Commercial High Schools using data mining

Abstract

The National Association of Commercial High Schools, a public interest incorporated foundation established with the aim of contributing to the development and improvement of commercial education in high schools, conducts a variety of qualification examinations. In this study, one of these tests, the “English Proficiency Test” is focused on and examined in terms of metrical linguistics. In short, frequency characteristics of character- and word-appearance are investigated using a program written in C++. These characteristics are approximated by an exponential function. Furthermore, the percentage of Japanese junior high school required vocabulary and American basic vocabulary is calculated to obtain the difficulty-level of each material.