TY  - JOUR
AU  - Echenique,Federico
AU  - Fryer,Roland G., Jr.
TI  - On the Measurement of Segregation
JF  - National Bureau of Economic Research Working Paper Series
VL  - No. 11258
PY  - 2005
Y2  - April 2005
UR  - http://www.nber.org/papers/w11258
L1  - http://www.nber.org/papers/w11258.pdf
N1  - Author contact info:
Federico Echenique
Humanities and Social Sciences, MC 228-77
California Institute of Technology
1200 East California Boulevard
Pasadena, CA 91125
Tel: 626/395-4273
Fax: 626/405-9841
E-Mail: fede@hss.caltech.edu

Roland G. Fryer, Jr
Department of Economics
Harvard University
Littauer Center 208
Cambridge, MA  02138
Tel: 617/495-9592
Fax: 617/495-8570
E-Mail: rfryer@fas.harvard.edu
AB  - This paper develops a measure of segregation based on two premises: (1) a measure of segregation should disaggregate to the level of individuals, and (2) an individual is more segregated the more segregated are the agents with whom she interacts. Developing three desirable axioms that any segregation measure should satisfy, we prove that one and only one segregation index satisfies our three axioms, and the two aims mentioned above; which we coin the Spectral Segregation Index. We apply the index to two well-studied social phenomena: residential and school segregation. We calculate the extent of residential segregation across major US cities using data from the 2000 US Census. The correlation between the Spectral index and the commonly-used dissimilarity index is .42. Using detailed data on friendship networks, available in the National Longitudinal Study of Adolescent Health, we calculate the prevalence of within-school racial segregation. The results suggests that the percent of minority students within a school, commonly used as a substitute for a measure of in-school segregation, is a poor proxy for social interactions.
ER  -