Does receiving a gift encourage the recipient to send more gifts ? Causal identification of behavioral contagion is very challenging , especially based on observational datafrom social networks. Given that the online monetary gift (also known as a "red packet") in WeChat groups is randomly split between group members, we are able to conduct a natural experiment to identify the causal effect of receiving online red packets on the contagion of gift exchange. Analyzing gifting behavior using a large-scale dataset of 3.4 million WeChatusers, we find that recipients on average repay 18.29\% of the amount they receive. Moreover, our analysis shows that recipients' contagion may be driven by different types of reciprocity. We further find thatthe "luckiest draw" recipients repay 1.5 times more than other recipients, and identify a group norm that luckiest draw recipients should send payment back to the group .
Our study seeks to identify the social contagion of in-group gifts: if gifts trigger their recipients to send more gifts subsequently, the actual impact of a gift on group dynamics would be greatly amplified. Causal identification of contagion is always challenging in observational data; To identify gift contagion, we leverage a natural experiment using a large sample of 36 million online red packets sent within 174,131 chat groups on WeChat, one of the largest social network services worldwide. Our natural experiment is enabled by WeChat's random gift amount algorithm, with which the amount that a user receives does not depend on her own attributes. We find that, on average, receiving one more dollar causes a recipient to send 18 cents back to the group within the subsequent 24 hours. Moreover, this effect is much stronger for "luckiest draw" recipients or those who receive the largest share from a red packet, suggesting a group norm according to which the luckiest draw recipients should send the first subsequent red packets. Additionally, we find that gift contagion is affected by in-group friendship network properties, such as the number of in-group friends and the local clustering coefficient .
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Does receiving a gift encourage the recipient
Our study seeks to identify the social contagion of in-group gifts: if gifts trigger their recipients
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subsequently, the actual impact of a gift on group dynamics would be greatly amplified.
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behavioral contagion is very challenging , especially based on observational datafrom social networks. Given that the online monetary gift (also known as a "red packet") in WeChat groups is randomly split between group members, we are able to conduct
contagion is always challenging in observational data; To identify gift contagion, we leverage
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to identify the causal effect of receiving
using a large sample of 36 million
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on the contagion of gift exchange. Analyzing gifting behavior using a large-scale dataset of 3.4 million WeChatusers, we find that recipients on average repay 18.29\% of the amount they receive. Moreover, our analysis shows that recipients' contagion may be driven by different types of reciprocity. We further find thatthe
sent within 174,131 chat groups on WeChat, one of the largest social network services worldwide. Our natural experiment is enabled by WeChat's random gift amount algorithm, with which the amount that a user receives does not depend on her own attributes. We find that, on average, receiving one more dollar causes a recipient to send 18 cents back to the group within the subsequent 24 hours. Moreover, this effect is much stronger for
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repay 1.5 times more than other recipients, and identify
or those who receive the largest share from a red packet, suggesting
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according to which the
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payment back to the group
the first subsequent red packets. Additionally, we find that gift contagion is affected by in-group friendship network properties, such as the number of in-group friends and the local clustering coefficient