Why is violence high and persistent in deprived communities? A formal model

Area of Science:

• Social Sciences
• Economics
• Criminology

Background:

• Rates of violence exhibit significant variation across time and geography.
• Violence is positively correlated with economic deprivation and inequality.
• Local persistence, or enduring neighborhood effects, is a characteristic of violence rates.

Purpose of the Study:

• To identify a single mechanism explaining variations in violence rates.
• To formalize this mechanism in a mathematical model.
• To explore the implications for policy and interventions.

Main Methods:

• Development of a mathematical model of individual-level processes generating population-level patterns.
• Simulation of populations with heterogeneous resource levels.
• Analysis of the relationship between resource levels, desperation, and violence.

Main Results:

• High deprivation/inequality increases desperate individuals, raising exploitation risk and making violence advantageous as a 'toughness signal'.
• Intermediate poverty levels can lead to bistability and hysteresis, where past deprivation perpetuates violence.
• The model successfully reproduces observed variations in violence rates, enduring neighborhood effects, and hysteresis.

Conclusions:

• A unified mechanism based on resource desperation and signaling explains key patterns in violence.
• Hysteresis demonstrates how past socioeconomic conditions can have lasting impacts on violence.
• Findings offer insights for developing targeted interventions to reduce violence.