Tag
peer_effects
14 findings
EducationClass Size Reduction IneffectivenessThe indirect treatment effect on non-remedial students remaining in smaller, more homogeneous classrooms was 0.133 standard deviations (statistically insignificant, with a 95% confidence interval ranging from -0.076 to 0.189).RCTBehaviour & psychologyFriendship Network Social ReinforcementFully treated friendship networks produced a 0.46 standard deviation increase in knowledge (versus 0.28 SD for students with zero treated friends) and a 0.24 standard deviation increase in positive sexual attitudes (versus 0.04 SD for students with zero treated friends).RCTEducationHeterogeneous Peer Preference SortingDemonstrates that under heterogeneous student preferences across curricula (such as commercial versus academic/industrial tracks), student sorting increases average aggregate utility without imposing negative peer externalities on non-participants.Expert TheoryEconomics (general)Community Incentive and Distance Instrumental Variable MethodThe first-stage regression predicting the proportion of village members learning HIV results yields a strong F-statistic of 23.98 without controls, with an average of 72.3% of village members learning test results (SD = 0.186).RCTLabour & employmentIntra-Production Line Soft Skill Productivity SpilloversUntrained workers on treatment lines accrued 8.02 additional person days during treatment (p < 0.05) and experienced efficiency gains of 7.14 percentage points post-treatment (over two-thirds the size of direct treatment effects), leading to an overall line-level efficiency increase of 4.31 percentage points (p < 0.05).RCTEducationLinear-in-Means Peer Externalities ModelThe theoretical framework demonstrates that under linear-in-means peer assumptions, student re-sorting does not alter aggregate population test scores ($\bar{Y} = \beta_0 \bar{X} + \beta_1 \bar{X}$); individual gains are strictly offset by losses to non-participants unless $\beta_2 > 0$.Expert TheoryEducationNon-Peer Productive Voucher GainsAmong vocational applicants, voucher winners attended schools where peers were 25% less likely to attend college and 33% more likely to drop out. Despite worse peer characteristics, voucher winners experienced a 25% increase in high school graduation likelihood and a 0.33 to 0.66 standard deviation increase in college entrance exam (ICFES) scores.RCTCrime & justicePeer Group Composition Constraints in Program TargetingWhile 100% of crime reduction cost savings ($652–$1,250 per participant) stem from the 3% at-risk subgroup, universal open-enrollment programs embed at-risk youth in a broader peer group where 97% of participants have no criminal record, preventing adverse peer contagion.Expert TheoryEducationPost-Randomization Peer Compositional StabilityAssigned teacher effectiveness showed no statistically significant relationship with peer baseline math scores (coefficient = 0.246, SE = 0.164) or other peer traits; joint hypothesis p-values were 0.405 for grades 4–8 and 0.321 for high school, proving post-randomization peer stability.RCTEducationPeer Effects Overcontrolling in Value-Added ModelsThe component removed by peer effect controls predicted student achievement after random assignment with a coefficient of 1.150 (p < 0.01, SE = 0.336), proving it contains causal teacher effectiveness. In contrast, the component removed by individual baseline score controls yielded a coefficient of 0.047 (SE = 0.042), showing baseline score controls successfully remove non-teacher sorting noise.RCTLabour & employmentPeer Productivity SpilloversSitting near a peer with above-average productivity increased an individual worker's output by 5%, driven primarily by an increase in total hours worked rather than speed per unit of time, and increased the worker's probability of choosing commitment contracts by 5 percentage points.RCTBehaviour & psychologyPeer Saturation and Information DiffusionEvaluates whether achieving a 75% training saturation threshold in local administrative units increases social spillover effects and program uptake compared to a 25% threshold.RCTSociety & networksSemantically Weighted Peer Networks and Multidimensional Communication BalanceAggregate interaction flows between peers across business-weighted and sentiment-weighted networks exhibit a high positive correlation ($r = 0.699$), and both correlate strongly with the unweighted benchmark network ($r = 0.821$ and $r = 0.951$, respectively). Virtual-within peer effects on proposal submission remain virtually identical across benchmark ($\beta = 0.533, p < 0.01$), business ($\beta = 0.521, p < 0.01$), and sentiment ($\beta = 0.530, p < 0.01$) networks.RCTMethods & evidenceWorkplace Batching and Peer Isolation ProtocolControl group workers showed zero output decline on Day 9 after witnessing Wave A treatment workers receive early cash payouts, confirming the absence of relative fairness spillover.RCT