Capturing gender-based microsegregation: A modified ratio index for comparative analyses

Comparative studies of occupational sex segregation have employed a variety of measures to estimate the extent of segregation across labor markets. In this article, the authors focus on two intrinsic limitations of the ratio index, which is derived from the log-linear framework: singularity for totally segregated occupations and sensitivity near the extremes. To capture the real essence of gender occupational segregation, it is necessary to examine rather detailed occupational categories. Such detailed occupational classification poses a problem for the ratio index since small occupations are more likely to be mono-gender occupations. The authors propose an alternative modified index that resolves both the singularity and the sensitivity problems by employing the "first-order approximation" of the logarithmic function. The modified index makes it possible to compute measures of microsegregation for detailed occupational categories. The advantages of the proposed index for comparative microsegregation analyses are illustrated and discussed.