Reducing Crime and Violence Experimental Evidence on Adult Noncognitive Investments in Liberia

The trial exposes poor, at-risk men to a mix of cognitive behavior therapy (CBT) and cash transfer in order to rehabilitate them from a life of petty crime, drug and anti-social behavior. A total of 999 at-risk youth were recruited for the study and assigned to one of the following treatment arms:
1) Cash only: a one-time cash disbursement of $200 – about three months wage - with no restrictions on usage.
2) Therapy: Eight week intervention in which twenty men met in groups three times a week, four hours at a time, led by two facilitators. On alternate days when groups did not meet, facilitators visited men at home or work to provide advising and encouragement. Therapy aimed to improve participants’ self-image and self-control.
3) Therapy and cash: After therapy ended, the men were given a one-time disbursement of $200.
4) Control: The men do not receive cash or therapy.

2011-03-11

2012-04-11

Changes in:
1) anti-social behavior
2) income
3) self-control
4) time preferences
5) anti-criminal and anti-violence values
6) others (pro-social behavior, mental health, self efficacy and esteem, appearance, substance abuse, quality of social networks, subjective wellbeing and executive function)

1) Anti-social behavior: selling drugs, fights, weapons, arrest, aggressive and hostile behavior, intimate partner abuse, political violence.
2) Income: (i) estimated earnings in all activities in the past two weeks; (ii) consumption in the past two weeks; and (iii) an index of durable assets.
3) Self-control: (i) 9 questions from the Barrett Impulsiveness Scale which assesses one’s inability to control thoughts and actions (ii) 8 questions from the NEO-five factor personality inventory to assess conscientious. Topics included following societal rules, and controlled, careful behavior (iii) 7 questions on perseverance from the GRIT scale which captures the ability to press on in the face of difficulty (iv) 8 questions on reward responsiveness—whether they are motivated by immediate, typically emotional rewards—from the Behavioral Inhibition/Behavioral Activation Scale.
4) Time preference: measured through incentivized games and survey questions to create a summary index of 4 measures of patience and 4 of time inconsistency.
5) Anti-criminal and anti-violence values: Self reported measures of towards violence and crime in their own lives. 11 questions were asked about using violence to solve personal problems, 12 questions about participating in crime as a livelihood and 6 about political violence. A composite index was creating using all three categories of questions.
6) Other outcomes: self-reported and various standardized testing instruments.

The experiment uses a 2x2 factorial design. In the first lottery, half the recruited men were assigned to therapy. In a second lottery, half the full sample of the participants was assigned to a cash grant. This created four treatment arms where 25% received both therapy and cash, 25% received only cash, 28% only therapy, and 22% to neither.

A pilot phase was first conducted with 100 men and given that there were no security issues, expanded to include 899 more. Participants were surveyed five times: baseline, two shortrun surveys at 2 and 5 weeks, and long run surveys at 12 and 13 months after grants. Given the sample men was extremely mobile, extensive effort was made to track individual participants, even travelling to different parts of the country to track them down. Ultimately, the resurvey rate was 92.7%. The other issue was that most responses were self-reported where individuals might be inclined to underreport stigmatized behavior such as gambling and criminal activity. To validate self-reported responses, a randomly chosen subsample of 240 participants were shadowed for four days by specially trained facilitators who recorded their findings without knowing what the original self-reported responses were.

Two different randomizations took place: one to assign therapy status and the other to assign cash grant status. Randomization was by public draw where men took turns drawing colored chips from a fabric bag.

Individual men

No

Study not clustered

999 men

Total: 999 men
Therapy: 277
Cash: 251
Therapy & cash: 249
Control: 222

It was estimated that the Minimum Detectible Effect for a sample size of 1,000 (with a quarter for each of the four treatment arms) would be a 0.12 standard deviation change in a standardized dependent variable for a two-tail hypothesis test with statistical significance of 0.05, statistical power of 0.80, an intra-cluster correlation of 0.25, and the proportion of individual variance explained by covariates as 0.10.

REDUCING CRIME AND VIOLENCE EXPERIMENTAL EVIDENCE ON ADULT NONCOGNITIVE INVESTMENTS IN LIBERIA

The paper shows that self-control, time preferences, and values are malleable in adults, and that investments in these skills and preferences reduce crime and violence. The authors recruited criminally-engaged Liberian men and randomized half to eight weeks of group cognitive behavioral therapy, fostering self-regulation, patience, and noncriminal values. They also randomized $200 grants. Cash alone and therapy alone dramatically reduced crime and violence, but effects dissipated within a year. When cash followed therapy, however, crime and violence decreased by as much as 50 percent for at least a year. They hypothesize that cash reinforced therapy’s lessons by prolonging practice and self-investment.

Blattman, Christopher, Julian Jamison, and Margaret Sheridan. “Reducing Crime and Violence: Experimental Evidence on Adult Noncognitive Investments in Liberia.” NBER Working Paper No. 21204, May 2015.

http://papers.ssrn.com/sol3/papers.cfm?abstract_id=2594868