We analyse pricing, effort and tipping decisions in the online service Google Answers. While users set a price for the answer to their question ex ante, they can additionally give a tip to the researcher ex post. In line with the related experimental literature we find evidence that tipping is...

Actual behaviour is influenced in important ways by moral emotions, for instance guilt or shame (see among others Tangney et al., 2007). Belief-dependant models of social preferences using the framework of psychological games aim to consider such emotions to explain other-regarding behaviour....

Intentions-based models of social preferences use the framework of psychological games and incorporate higher order beliefs and actions into the utility function. We test the robustness of two types of intentions-based models (guilt aversion and reciprocity). In addition to incentivised...