Date of Award

January 2018

Document Type


Degree Name

Master of Science (MS)


Economics & Finance

First Advisor

Cullen Goenner


This paper examines certain factors relating to collective efficacy; loosely defined as the strength of a community, and the effect those factors have on police homicides in the respective communities. More specifically, this study analyzes three components that contribute to collective efficacy: linguistic isolation, residential stability, and educational attainment. Data utilized in this study include U.S. Census data as well as data from a unique dataset containing California state-wide homicides during the 1990s. Using a negative binomial regression on pooled zip code data shows that, in relation to the factors mentioned above, educational attainment is the most influential characteristic analyzed in relation to police homicides, even more so than the racial makeup of a neighborhood. This result was found to be statistically significant at the 1% level. The results imply that for each percent increase of the persons without a high school diploma by the age of 25, the community sees a multiplicative rate of increase of 1.59 percent (IRR 1.0159) in the number of police homicides. Moreover, a one standard deviation increase in the percentage of high school dropouts by age 25 was associated with a 29.6% increase in the police homicide rate. The paper did not find any systematic relationship between the aforementioned focal components (linguistic isolation, residential stability, and educational attainment) of collective efficacy and that of victimization of African Americans by police officers. As such, in terms of policy recommendations, it would seem that additional public funds should be spent on local education and adult graduation rates to assist with the growing issue of police homicides.