An Introduction to Statistics in Linguistics (5) Whether There is a Difference in the Proportion

Abstract

Quantitative analysis of language is often stated using the difference of the proportion calculated from frequency of various survey items such as words, part of speech, etymological types, character types, co-occurrence words, and the number of people who answered "yes", by corpus surveys and questionnaire surveys. However, most corpus surveys and questionnaire surveys are sample surveys, not complete surveys. The proportion obtained from the sample survey should not be treated the same as the proportion of the population. Also, even when comparing proportions, the sample size must be stated. The ratio of 10/50 and 20/50 and the ratio of 4/20 and 8/20 are the same for the former 20% and the latter 40%, and the difference in ratio is 20 points, but in the latter case, it is not a statistically meaningful difference. In this paper, while showing some concrete examples together with the calculation formulas, we describe the points to be noted about whether there is a difference in the proportion. The statistical explanation is kept to a minimum, and it is shown by a calculation formula that can be understood by knowledge of four arithmetic operations and square roots.