What is trustworthiness and what drives it?

This paper experimentally isolates the impact of various combinations of the following motives on trustworthiness: (i) unconditional other-regarding preferences; (ii) vulnerability-responsiveness; (iii) deal-responsiveness; and (iv) gift-responsiveness. Our results indicate that – besides unconditional other-regarding preferences like altruism and inequality aversion – vulnerability-responsiveness is the most important driver for trustworthiness. Prompted by our experimental findings we provide behavioral definitions of trust, trustworthiness, and trust-responsiveness based on revealed willingness to accept vulnerability and the response to it. An important difference from existing definitions is that ours allow trust to be present without generosity. •Experiments are run to isolate the impact of various motives for trustworthiness.•Considered motives include vulnerability-, gift- and deal-responsiveness.•Vulnerability-responsiveness turns out to be the most important conditional motive.•Behavioral definitions of trust, trustworthiness and trust-responsiveness are provided.