Racial disparities in obesity in the United States are often assumed to reflect racial disparities in socio-economic status, diet, and physical-activity. Dr. Bisakha Sen, professor in the department of health care organization and policy at the University of Alabama at Birmingham School of Public Health, has presented an econometric method that helps examine this assumption by “decomposing” the racial gap in body-mass index (BMI) into how much can be explained by racial differences in “standard” predictors of BMI and how much remains unexplained.