Good Question! The Effect of Positive Feedback on Contributions to Online Public Goods

2026-04-11

AI Summary

This study addresses the challenge of declining user engagement in online Q&A communities by investigating how positive feedback incentivizes contributions. Conducting a pre-registered randomized controlled trial on Stack Overflow, the authors anonymously assigned upvotes to isolate and quantify the distinct effects of social recognition and algorithmic visibility—termed “algorithmic amplification”—on user behavior. Results show that receiving upvotes increases the likelihood of users posting new questions by 6.3% and answering others’ questions by 12.9% within four weeks. Notably, algorithmic amplification exerts a significant and sustained effect on answer contributions, persisting for up to twelve weeks. These findings reveal a novel mechanism through which positive feedback indirectly fosters broader community participation by enhancing content visibility.

Technology Category

• Humans and AI: Crowd Sourcing and Human Computation
• Cognitive Modeling & Cognitive Systems: Social Cognition And Interaction
• Application Domains: Humanities & Computational Social Science

Application Category

• Web Mining and Content Analysis: Community question answering
• Responsible Web: Human-perceived consequences of algorithmic deployment on the web
• Economics, Online Markets and Human Computation: LLM based quality controls for crowd work

Abstract

Online platforms where volunteers answer each other's questions are important sources of knowledge, yet participation is declining. We ran a pre-registered experiment on Stack Overflow, one of the largest Q&A communities for software development (N = 22,856), randomly assigning newly posted questions to receive an anonymous upvote. Within four weeks, treated users were 6.3% more likely to ask another question and 12.9% more likely to answer someone else's question. A second upvote produced no additional effect. The effect on answering was larger, more persistent, and still significant at twelve weeks. Next, we examine how much of these effects are due to algorithmic amplification, since upvotes also raise a question's rank and visibility. Algorithmic amplification is not important for the effect on asking additional questions, but it matters a lot for the effect on answering other questions. The increase in visibility increases the probability that another user provides an answer, and that experience appears to shift the poster toward broader community participation.

Problem

• online public goods
• positive feedback
• user participation
• algorithmic amplification
• Q&A platforms

Innovation

• positive feedback
• online public goods
• algorithmic amplification
• randomized experiment
• community participation