Internet experiment

We explore the effects of social distance in experiments conducted over the Internet on three continents, in classroom laboratory sessions conducted in Israel and Spain, and in computer sessions pairing participants from different states, one in Texas and the other in California. Our design elicits individual behavior profiles over a range of contingencies, enabling us to identify heterogeneity among our participants. We find that many people show regard for others, even with the apparent social distance inherent with Internet interaction. In all cases, a substantial minority makes choices indicating positive reciprocity; the proportion doing so varies inversely with social distance