[Paper Review] How to Ask for a Favor: A Case Study on the Success of Altruistic Requests

Tim Althoff, Cristian Danescu-Niculescu-Mizil+1 more|arXiv (Cornell University)|May 13, 2014

Spam and Phishing DetectionComputer Science41 references56 citations

TL;DR

This study investigates the success factors of altruistic requests in online communities by analyzing 1,500+ requests for free pizza on Reddit's r/Random_Acts_Of_Pizza, where all requests seek identical rewards with no tangible return. Using NLP and social network analysis, it identifies that clear narratives expressing need, linguistic cues of gratitude and evidentiality, generalized reciprocity, and high asker status significantly increase success likelihood, while sentiment and politeness do not.

ABSTRACT

Requests are at the core of many social media systems such as question & answer sites and online philanthropy communities. While the success of such requests is critical to the success of the community, the factors that lead community members to satisfy a request are largely unknown. Success of a request depends on factors like who is asking, how they are asking, when are they asking, and most critically what is being requested, ranging from small favors to substantial monetary donations. We present a case study of altruistic requests in an online community where all requests ask for the very same contribution and do not offer anything tangible in return, allowing us to disentangle what is requested from textual and social factors. Drawing from social psychology literature, we extract high-level social features from text that operationalize social relations between recipient and donor and demonstrate that these extracted relations are predictive of success. More specifically, we find that clearly communicating need through the narrative is essential and that that linguistic indications of gratitude, evidentiality, and generalized reciprocity, as well as high status of the asker further increase the likelihood of success. Building on this understanding, we develop a model that can predict the success of unseen requests, significantly improving over several baselines. We link these findings to research in psychology on helping behavior, providing a basis for further analysis of success in social media systems.

Motivation & Objective

• To understand what drives the success of altruistic requests in online communities where no tangible reward is offered.
• To disentangle the effects of what is requested from linguistic and social factors influencing request success.
• To identify specific textual and social features that predict whether a request will be fulfilled.
• To extend findings from social psychology to online peer-to-peer giving contexts, particularly in the absence of external incentives.

Proposed method

• Collected and analyzed 1,500+ requests from r/Random_Acts_Of_Pizza, where all requests seek the same reward: a free pizza.
• Extracted high-level social features from text using social psychology frameworks, such as perceived need, gratitude, evidentiality, and generalized reciprocity.
• Measured asker status via Reddit karma and subcommunity activity to assess social influence on request success.
• Used logistic regression models to predict request success based on linguistic, social, and temporal features, comparing against multiple baselines.
• Controlled for confounding variables by focusing on a single request type (pizza) and single-giver fulfillment model.
• Evaluated the predictive power of features like narrative clarity, sentiment, and user similarity against a null model.

Experimental results

Research questions

• RQ1 What linguistic features in a request significantly increase the likelihood of being fulfilled in an altruistic online context?
• RQ2 How do social factors such as the asker’s status or perceived need influence the success of a request?
• RQ3 To what extent do psychological principles like generalized reciprocity and gratitude predict request success?
• RQ4 Does sentiment or politeness in the request text correlate with higher success rates when no reward is offered?
• RQ5 How do narrative structures expressing need or urgency compare in effectiveness to requests based on craving or desire?

Key findings

• Requests that clearly express a narrative of need—such as financial hardship or lack of food—were significantly more likely to succeed than those based on craving or desire.
• Linguistic cues indicating gratitude and evidentiality (e.g., 'I’ve been struggling to find work') were strong predictors of success, even after controlling for other factors.
• Users with higher Reddit karma or greater subcommunity engagement were significantly more likely to have their requests fulfilled, indicating that status enhances success likelihood.
• Generalized reciprocity—e.g., expressing a desire to 'pay it forward'—was associated with higher success, suggesting prosocial framing increases appeal.
• Contrary to expectations, the sentiment of the request text (positive or negative) showed no significant correlation with success when controlling for other variables.
• User similarity, measured by shared subcommunity membership, did not significantly differ between successful and unsuccessful request pairs, indicating that similarity alone does not drive success in this context.