Let (not) your left hand know what your right hand does. A field experiment on the role of signalling motivation in donation behaviour
Tommaso Reggiani 
Matteo Rizzolli 
Fabio Sabatini 
Prosocial actions, such as donation in support of a cause, may be driven by both intrinsic and extrinsic motivations. Laboratory studies have shown that, to the extent to which prosocial behaviour can signal to others that one is “good”, signalling may work as a powerful extrinsic incentive. But what happens when an action can be perceived both as prosocial or antisocial depending on the point of view? How does signalling influence giving behaviour in scenarios where, for their donation, individuals can be seen as good or bad by others with virtually the same likelihood? We present and discuss a field experiment designed to respond to these so far unanswered questions. The experiment was held in the context of a fundraising initiative aimed at supporting a controversial legal action against the outcome of an open competition for assistant professor in Economics. We find that donations are U-shaped with the power of signalling. This effect is stronger for those donors who are more sensitive to the potential image-related costs and benefits associated with their donation behaviour. Several interpretations of these findings are discussed.
Keywords: incentives; motivations; signalling; prosocial behaviour; field experiment
JEL Codes: D64, C93, Z13
 SECS Team and Sapienza University of Rome, Department of Economics and Law. Email: email@example.com.