Tax & Revenue
Compliance, enforcement, and administrative simplification.
5 positive
5
experiments
3
replicated
Notable experiment
Social Norm Tax Letters →By Policy Area
Evidence organized by domain.
The registry holds 132 experiments. This section organizes them by policy domain — showing what the accumulated evidence says about each area, where it is strong, and where it is thin.
Basic Income
Unconditional cash, guaranteed income pilots, and direct transfer programs.
3 positive1 mixed
4
experiments
0
replicated
Notable experiment
Finland Basic Income Experiment →Benefits Enrollment
Take-up of public programs and friction reduction in eligibility systems.
5 positive1 null2 mixed
8
experiments
2
replicated
Notable experiment
SNAP Enrollment Information Letters for Seniors →Cash Transfers
Conditional and unconditional income support programs.
4 positive1 mixed
5
experiments
2
replicated
Notable experiment
PROGRESA Conditional Cash Transfer →Energy & Environment
Conservation, emissions, and behavior change for environmental outcomes.
6 positive
6
experiments
4
replicated
Notable experiment
Opower Home Energy Reports →Education
Schools, class size, curriculum, and learning outcomes.
8 positive2 mixed
10
experiments
2
replicated
Notable experiment
Universal Free School Breakfast Program →Early Childhood
Prenatal through age 5 — the highest-return period for public investment.
8 positive
8
experiments
2
replicated
Notable experiment
Nurse-Family Partnership — Elmira Trial →Libraries
Public library programming, attendance, and community services.
3 positive
3
experiments
3
replicated
Notable experiment
Library Fine Elimination →Public Health
Coverage, behavior change, and health system design.
8 positive3 null7 mixed
18
experiments
9
replicated
Notable experiment
SMS Reminders for Childhood Vaccination — Meta-Analysis →Parks & Public Space
Physical environment, community space, and active living.
2 positive
2
experiments
0
replicated
Notable experiment
Community Park Advisory Boards →Administrative Process
Government service delivery, permit systems, and bureaucratic friction.
6 positive
6
experiments
1
replicated
Notable experiment
SMS Wait Time Notifications for NHS Appointments →Voter Engagement
Turnout, registration, and civic participation.
7 positive
7
experiments
6
replicated
Notable experiment
Voter Registration Postcards to Unregistered Eligible Citizens →Housing
Mobility, affordability, eviction prevention, and neighborhood effects.
6 positive1 mixed
7
experiments
3
replicated
Notable experiment
At Home / Chez Soi — Housing First →Public Safety
Crime reduction, policing strategies, and community violence intervention.
12 positive4 null1 negative4 mixed
21
experiments
11
replicated
Notable experiment
Philadelphia Hot Spots Policing →Financial Services
Savings, retirement, credit access, and behavioral finance.
8 positive2 mixed
10
experiments
4
replicated
Notable experiment
Commitment Savings Accounts for Agricultural Workers →Transportation
Congestion, mode-shift, transit demand, and road safety.
6 positive
6
experiments
4
replicated
Notable experiment
5p Plastic Bag Charge →International Development
Poverty reduction programs in low- and middle-income countries.
13 positive1 mixed
14
experiments
8
replicated
Notable experiment
Colombia Familias en Acción →