Lie to Me: Lying Virtual Agents Dissertaç˜ao para obtenç˜ao do Grau de Mestre em Engenharia ...

82 Pages·2012·1.33 MB·English

Lie to Me: Lying Virtual Agents
Henrique Daniel Santar´em Reis
Disserta¸ca˜o para obtenc¸˜ao do Grau de Mestre em
Engenharia Inform´atica e de Computadores
Ju´ri
Presidente: Professor Doutor Joaquim Armando Pires Jorge
Orientador: Professora Doutora Ana Maria Severino de Almeida e Paiva
Vogal: Professor Doutor Nuno Manuel Mendes Cruz David
Maio 2012
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Acknowledgements
First I would like to thank IST-Taguspark, INESC-ID and GAIPS for the condition which
enabled me to develop my work. To my advisor Ana Paiva, for all the support, motivation and
opportunity to work at GAIPS.
I would also like to thank everyone at GAIPS for their help throughout my work. A special
thanks to Jo˜ao Dias for following my work closely, for the new ideas, discussions and supporting
me in the hardest moments. Another special thanks to Henrique Campos, Joana Almeida and
Andr´e Carvalho for great companionship, support and for enduring this journey with me.
Finally, to my parents and girlfriend, who provided the greatest amount of motivation.
Lisboa, May 14th 2012
Henrique Reis
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To my family and girlfriend for all their
support and patience
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Resumo
O objectivo da nossa tese foi o de dotar agentes virtuais com a capacidade de modelar a mente
de outros agentes e usar essa informa¸c˜ao no seu racioc´ınio. Estendemos uma arquitectura j´a
existentecomumn´ıveldeTeoriadaMenteparaNn´ıveis. Quisemosavaliarseagentescapazesde
utilizarmaisdoqueumn´ıvelseriampercepcionadoscomosendomaisinteligentesemcomparac¸˜ao
com agentes que apenas usam um n´ıvel, focando-nos na noc¸˜ao de engano. Revimos conceitos-
chave sobre este assunto utilizando trabalhos espec´ıficos da ´area de Psicologia que se focavam
em enganar, mentira e Teoria da Mente, assim como trabalhos que tinham como objectivo
implementar sistemas num contexto parecido a este. Descrevemos o modelo conceptual que
desenh´amos para alcan¸car o objectivo a que nos propusemos, seguindo depois para a descri¸c˜ao
de como foi implementado. Para avaliar o nosso trabalho desenvolvemos um cen´ario de estudo
baseado num jogo de bluff e mentira, fazendo duas vers˜oes, uma com um n´ıvel de Teoria de
Mente e outra com dois. Grav´amos a aplica¸c˜ao a correr e fizemos v´ıdeos de demonstrac¸˜ao para
avaliar a diferenc¸a do comportamento do agente mentiroso nas duas vers˜oes. A avalia¸c˜ao foi
composta por testes preliminares, de simula¸c˜ao e atrav´es de um question´ario final, sendo esta
u´ltima parte feita com 60 participantes. Os nossos resultados demonstraram-se consistentes
com a nossa hip´otese de que quanto maior o n´ıvel de abstrac¸c˜ao de Teoria da Mente, melhor os
agentes conseguem realizar tarefas que implicam enganar outr´em.
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Abstract
The objective of this thesis was to endow agents with the ability to model the mind of other
agentsandtousethisinformationontheirreasoningprocess. Wewantedtoassessifareasoning
ability capable of more then one level would be perceived as more socially intelligent than
one with only one level, focusing our work on deception behaviour generation. Key concepts
were reviewed regarding this topic, such as research work in the field of Psychology focused on
deception, telling lies and Theory of Mind, in addition to some works which tried to implement
systems with a similar goal. We proceeded by describing the conceptual model to achieve
our proposed goal, based on the Mindreading model of Baron-Cohen, to update N levels of a
Theory of Mind. An implementation specification was describe, explaining how we implemented
our model using an existing autonomous agent architecture and other frameworks. For the
evaluation stage we developed a case study based on a deception game and made two version
of liars: a one level and a second level Theory of Mind. We recorded the application running
and made demonstration videos to evaluate the differences in the deceptive behaviour. The
evaluation itself was composed of preliminary, simulation and a final questionnaire. The latter
were performed with 60 participants. The results showed to be consistent with our hypothesis
that the more reasoning abstraction level of a Theory of Mind, the better agents can performed
deceptive tasks.
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