This Discussion paper has been substantially revised, and is now available under the title "Why do promises affect trustworthiness, or do they?" in Experimental Economics, June 2016, Volume 19, Issue 2, pp 382–393; http://link.springer.com/article/10.1007%2Fs10683-015-9444-1 We set out to test...

We implement a trust game in which the trustee can write a free-form pre-play message for the trustor. The main twist in our design is that there is a 50% probability that the message is delivered to the trustor and a 50% probability that the message is replaced by an empty sheet. We find that...