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Self-Assessment: The Role of the Social Environment
Last registered on August 14, 2020


Trial Information
General Information
Self-Assessment: The Role of the Social Environment
Initial registration date
August 14, 2020
Last updated
August 14, 2020 9:55 AM EDT
Primary Investigator
LMU Munich & briq
Other Primary Investigator(s)
Additional Trial Information
Start date
End date
Secondary IDs
The aim of this study is to present descriptive and causal evidence on the role of the social environment in shaping the accuracy of self-assessment. We introduce a novel incentivized measurement tool to measure the accuracy of self-assessment among children and use this tool to compare children from high socioeconomic status (SES) families to children from low SES families. To move beyond correlational evidence, we will explore the effects of the randomized participation in a mentoring program designed to enrich the social environment of children.
External Link(s)
Registration Citation
Kosse, Fabian. 2020. "Self-Assessment: The Role of the Social Environment." AEA RCT Registry. August 14. https://doi.org/10.1257/rct.6287-1.0.
Experimental Details
Intervention Start Date
Intervention End Date
Primary Outcomes
Primary Outcomes (end points)
Accuracy of Self-Assessments: We designed an experimental paradigm with three main goals in mind. The paradigm should: (i) provide children with cues about their skills such that a higher self-assessment ability can manifest itself. At the same time, there should be no ability differences or differences in experience with respect to the specific paradigm between treatment groups; (ii) provide an incentivized measure that reflects the accuracy of self-assessments; (iii) be intuitive and easy to comprehend for children of age eight or nine. The latter goal, in particular, posed a challenge.
Primary Outcomes (explanation)
Secondary Outcomes
Secondary Outcomes (end points)
Secondary Outcomes (explanation)
Experimental Design
Experimental Design
We used official registry data to obtain the addresses of families (with children aged from seven to nine) living in the German cities of Bonn and Cologne. Families were contacted via postal mail and informed about the possibility to take part in the mentoring program and the interviews. We informed parents that participation in the mentoring program was not guaranteed due to limited capacity. The interested families were asked to fill out and return a short questionnaire concerning the socioeconomic characteristics of the household and to sign a non-binding letter of intent to take part in the interviews and the mentoring program. We received 1,626 complete responses and, based on the questionnaire, we categorized respondents as either high or low-SES households. SES reflects the level of resources available at the household level, i.e., material, educational, and time resources. Accordingly, a household was classified as low SES if at least one of the three following criteria was met: Low income: Equivalence income of the household is lower than 1,065 Euro. This corresponds to the 30\% quantile of the German income distribution. (ii) Low education: Neither the mother nor the father of the child has a school-leaving degree qualifying for university studies. (iii) Single-parent status: A parent is classified as a single parent if he/she is not living together with a partner.

All low-SES families that expressed interest were invited to take part in the study. To take part, families had to participate in a baseline wave of interviews (fall 2011) and provide written consent to allow the transmission of their addresses to the mentoring program. Importantly, the mentoring program could only accommodate 212 families; hence, out of 590 low-SES families who participated in the baseline wave and gave consent, 212 were randomly selected and constitute our treatment group (Treatment Low SES). The remaining 378 families form the control group (Control Low SES). Randomization was stratified by city (Cologne or Bonn) and SES criteria, for a total of 14 strata. Given the larger relative supply of mentors in Bonn, we assigned a higher share of children in Bonn to the treatment group. Thus, the assignment into treatment was random conditional on location. Therefore, we condition on location for the analyses.

We also invited 150 randomly-chosen high-SES families to take part in the study (not the mentoring program). 122 took part in the baseline wave of interviews and serve as an additional benchmark group (Control High SES).

After the one-year mentoring program, all families that participated in the baseline wave (Treatment Low SES, Control Low SES, and Control High SES) were invited to take part in the post-treatment interviews and experiments (post-treatment wave) in which all of our main outcome variables were elicited.

We exogenously enhanced the social environment of the treated low-SES families with the help of an existing and well-established non-profit mentoring program in Germany, ``Balu und Du''. In this program, elementary school children are provided with a mentor for up to one year. The mentors are predominantly university students (aged from 18 to 30) who volunteer to serve as a mentor for a child. The mentoring program is not targeted toward specific learning goals (such as improved school grades), but rather to enriching children’s everyday lives. A key component of the program is to introduce children to new activities, enable new experiences, and provide feedback; possibly exactly the inputs that are needed for them to develop an accurate sense of their abilities and that might be missing in low-SES families. In practical terms, a mentor typically spends one afternoon per week in one-to-one interactions with his/her mentee. During this time, they engage in joint activities such as cooking, sports, handicraft work, or visiting a zoo, museum, or playground.
Experimental Design Details
Randomization Method
We uses stratified randomization by city (Cologne or Bonn) and SES criteria. Randomization was done in office by a computer.
Randomization Unit
Was the treatment clustered?
Experiment Characteristics
Sample size: planned number of clusters
590 children
Sample size: planned number of observations
590 children
Sample size (or number of clusters) by treatment arms
Out of 590 low-SES families who participated in the baseline wave and gave consent, 212 were randomly selected and constitute our treatment group (Treatment Low SES). The remaining 378 families form the control group (Control Low SES).
Minimum detectable effect size for main outcomes (accounting for sample design and clustering)
IRB Name
IRB Approval Date
IRB Approval Number
Post Trial Information
Study Withdrawal
Is the intervention completed?
Intervention Completion Date
January 31, 2013, 12:00 AM +00:00
Is data collection complete?
Data Collection Completion Date
March 31, 2013, 12:00 AM +00:00
Final Sample Size: Number of Clusters (Unit of Randomization)
494 children
Was attrition correlated with treatment status?
Final Sample Size: Total Number of Observations
494 children
Final Sample Size (or Number of Clusters) by Treatment Arms
Control: 314 children Treatment: 180 children
Data Publication
Data Publication
Is public data available?
Program Files
Program Files
Reports, Papers & Other Materials
Relevant Paper(s)