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Randomized Field Experiment on Determinants of Self-employed Worker's Participation in Public Pension
Initial registration date
April 28, 2018
May 01, 2018 10:24 AM EDT
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Japan International Cooperation Agency (JICA)
Other Primary Investigator(s)
Asian Development Bank
Additional Trial Information
This study aims to investigate the reasons why the take-up rate of the public pension for self-employed workers such as herders in Mongolia is low and find effective policies to increase the take-up rate. We distribute different types of leaflets to local community (bagh) meeting participants with conducting a questionnaire survey to study their impact on take-up rate. We target 690 baghs in eight provinces, stratified at the province level and herder's population share within provinces. We will analyze the impact on take-up and contribution using administrative records.
Sawada, Yasuyuki, Tomoaki Tanaka and Junichi Yamasaki. 2018. "Randomized Field Experiment on Determinants of Self-employed Worker's Participation in Public Pension." AEA RCT Registry. May 01.
We randomly distribute different kinds of explanatory material about the social insurance. In collaboration with the Social Insurance General Office of Mongolia, we create four sets of leaflets. All of the leaflets include general information about the public pension, along with the following additional information:
(Control) General information about the public pension only,
(Treatment 1) Survivors and disability pension, supplementary to the public pension,
(Treatment 2) Japanese official assistance for the public pension administration for consolidating the trust, and (Treatment 3) Mobile banking payment for reducing the transaction cost.
Intervention Start Date
Intervention End Date
Primary Outcomes (end points)
Our main outcomes are (1) the voluntary social insurance take-up, (2) the payment of the social insurance contributions based on administrative records.
Primary Outcomes (explanation)
Secondary Outcomes (end points)
Secondary Outcomes (explanation)
We distribute different types of leaflets to local community (bagh) meeting participants with conducting a questionnaire survey to study which information can increase take-up. We target 690 baghs in eight provinces, stratified at the province level and herders' population share within provinces from March to October in 2017. When distributing the leaflets, we conduct a survey at the same time to collect basic information such as age and time and risk preferences. We will analyze the impact on take-up and contribution using administrative records covering the data before and after the distribution, which will be available in May/2018.
Experimental Design Details
We conducted randomization in office by a computer.
The randomization was conducted at the local community level.
Was the treatment clustered?
Sample size: planned number of clusters
690 local communities
Sample size: planned number of observations
Approximately 38,000 individuals
Sample size (or number of clusters) by treatment arms
173 local communities control (general information only), 168 local communities treatment 1 (survivors and disability pension), 170 local communities treatment 2 (Japanese official assistance), 179 local communities treatment 3 (mobile banking)
Minimum detectable effect size for main outcomes (accounting for sample design and clustering)
INSTITUTIONAL REVIEW BOARDS (IRBs)
The research ethics committee at the University of Tokyo
IRB Approval Date
IRB Approval Number