President's Professor and Head, Computer Science Department, Carnegie Mellon University
Fellows of ACM and IEEE
Towards a Theory of Trust in Networks of Humans and Computers
How can I trust the information I read over the Internet? We argue that a general theory of trust in networks of humans and computers must be built on both a theory of behavioral trust and a theory of computational trust. This argument is motivated by increased participation of people in social networking, crowdsourcing, human computation, and socio-economic protocols, e.g., protocols modeled by trust and gift-exchange games, norms-establishing contracts, and scams. User participation in these protocols relies primarily on trust: trust in both the computational elements in the network and the human element. Thus, towards a general theory of trust, to computational trust, we add behavioral trust, a notion from the social and economic sciences. Behavioral trust captures participant preferences (i.e., risk and betrayal aversion) and beliefs in the trustworthiness of other protocol participants. We argue that a general theory of trust should focus on the establishment of new trust relations where none were possible before. This focus would help create new economic opportunities by increasing the pool of usable services, removing cooperation barriers among users, and at the very least, taking advantage of network effects. Hence a new theory of trust would also help focus security research in areas that promote trust-enhancement infrastructures in human and computer networks.