DID YOU KNOW? A person who buys a Ferrari will likely begin to value speed over safety in order to avoid dissonance.

1. IS THIS JUST A POSTER DAY? Cosimo Nobile Supervisor: Dr Floriana Grasso Department of Computer Science The authors are trying to persuade the audience about the worthiness of their research. If you thought that this poster day was just part of the university training program let me tell you, from a communication point of view, there is much more going on! The audience might subsequently need to revise some beliefs in order to accept new information. These two aspects of our every day life are not so different as they may seem, they can be seen as two sides, social and cognitive, of the same epistemic coin. there is of course a discrepancy between the technicality and constraints of the theories and the real thing. BU IN OUR CONTEXT… The increasing number of people using the Internet to support their healthcare, provides new opportunities for pursuing public health objectives. We look at how to produce more persuasive pieces of advice to induce behavioural changes. Theories such as beliefrevision (how an individual changes his own mind), argumentation (how an individual tries to change other individuals’ mind by communication), together with other formal rational-choice models, attempt to mimic how humans reason, Little attention has been paid to the tendency for humans to preserve and reinforce our beliefs and attitudes through time for as long as we can,both for cognitive reasons (revising highly important beliefs, which might also explain and support many other beliefs, can be extremely costly) and for sociological reasons (in order to trust our beliefs we pay attention to very few, and carefully selected, information sources without being too fussy on reiterations). • DID YOU KNOW? • A person who buys a Ferrari will likely begin to value speed over safety in order to avoid dissonance. • The more you reward someone to tell a lie, the more public compliance you have but the less change in private opinion. • Millennial and messianic movements start proselytizing more as soon as their prophecies fail. • SO WHAT? • We argue that using CDT as the basis for modelling the user’s beliefs will bring into play the concept of motivation and active revision of beliefs and attitudes for free. • We also suggest that beliefs and attitudes should be structured and interconnected to form an “aristocratic network”, with cognitive dissonance acting as a major shaping force. • The magnitude of dissonance depends in fact strongly on the network’s structure: more intricately linked structures seem more capable of tolerating dissonance than more simply linked ones. We claim therefore that an argumentation model that takes into account such a structure will lead to more effective computer generated communication. Computational Model of Behaviour and Belief Change for Persuasive Dialogues COGNITIVE DISSONANCE According to this theory (CDT), there are some psychological phenomena that bias our beliefs, attitudes and behaviour toward a “dissonance reduction”. When one behaves in a way that runs counter to one’s beliefs or when new dissonant information arises, an aversive motivational state (cognitive dissonance) is created which pushes the individual towards a belief (or behaviour) change.