By Jesse Bruhn 

I study criminal street gangs using new data that describes the geospatial distribution of gang territory in Chicago and its evolution over a 15-year period. Using an event study design, I show that city blocks entered by gangs experience sharp increases in the number of reported batteries (6%), narcotics violations (18.5%), weapons violations (9.8%), incidents of prostitution (51.9%), and criminal trespassing (19.6%). I also find a sharp reduction in the number of reported robberies (-8%). The findings cannot be explained by pre-existing trends in crime, changes in police surveillance, crime displacement, exposure to public housing demolitions, reporting effects, or demographic trends. Taken together, the evidence suggests that gangs cause small increases in violence in highly localized areas as a result of conflict over illegal markets. I also find evidence that gangs cause reductions in median property values (-$8,436.9) and household income (-$1,866.8). Motivated by these findings, I explore the relationship between the industrial organization of the black market and the supply of criminal activity. I find that gangs that are more internally fractured or operate in more competitive environments tend to generate more crime. This finding is inconsistent with simple, market-based models of criminal behavior, suggesting an important role for behavioral factors and social interactions in the production of gang violence

Bravo Working Paper # 2021-004 . Brown University Orlando Bravo Center for Economic Research, 2021. 71p.

By Jerzy  Kochanowsk

This book analyzes the history of the black market in Poland before the 1940s and the development of black-market phenomena in post-war Poland. The author evaluates the interrelation between black-market phenomena and historical and geographical conditions. At first, the black market stabilized the system by making it more flexible and creating a margin of freedom, albeit in the short term. In the long run, the informal economic activities of the people ran counter to and undermined the official ideology of the state. The author concludes that in post-war Poland, owing to a singular coincidence of historical, political, economic and social factors, the second economy had its own unique character and an endemic presence that loomed large in the Soviet Bloc.

Bern: Peter Lang, 2017. 436p.