Measuring ethnic labour market concentration and segmentation

With the huge influx of immigrants into the United States in recent years, considerable efforts have been devoted to describing the extent and variation of labour market concentration across ethnic groups within or between regions. However, there is no consensus among social scientists on how to measure and identify ethnic labour market concentration patterns. The issues mainly include, firstly, how to define an employment sector - as an industrial or an occupational sector; secondly, how to break down employment categories; and thirdly the extent to which a job sector can be identified as an ethnic-concentrated sector, that is, what index and what threshold value should be used to define a 'niche' sector? Using the case of Chinese in the San Francisco Consolidated Metropolitan Statistical Area, this paper demonstrates how different choices could encourage different evalzuation and understanding of multi-ethnic urban labour market segmentation processes.