Miguel Rebollo

On the use of argumentation in agreement technologies
(Henry Prakken)

Agents need argumentation (i) for their internal reasoning and (ii) for their interaction with other agents. Explaining basic things about argumentation process: argument attacks. The situation of the dialog can be modeled in a graph colored by defining in and out arguments (Dung, 1995). And there is a sound and complete game that allows to determine if an argument is feasible or not without having to calculate the entire network: an argument A is feasible when there is a winning strategy for A follow.ing the game rules.

Problem: it is asumed that all information is centralized and static (a single theory -KB-) So dialogue game systems are developed. He’s using the Walton & Kreebe dialogue types (without eristic :-) I’ve seen this a lot of times already.

An Interesting thing: blocking behavior (always asking why) It can be solve by using sanctions:
social sanctions (i wont talk you any more)
shift of burden of proof by a third party (referee): q since r // why r? // referee: you must defend not-r

I already knew most of these things (thanks to Stella)

“Prof. Kripke, let me introduce Prof. Nash”, or
Logic for Automated Mechanism Design
(Mike Wooldridge)

In MAS the interaction is done by mechanisms = protocol + self-interest and agents are the participants in these mechanisms. So mech. can’t be treated as simple protocols. (ex. sniping in eBay -bidding in the last 5 min. trying to be the last bidder-). A MAS can predict the sniping behav. of users in eBay?  The environment of an agent is a mechanism too, that contains other agents that act strategically to achieve their own goals

The formalization used is ATL (alternate-time logic), introduced in 1997 top analyze games. It defines a branching-time model as a graph and CTL is the logic used to talk about branching-time structures, extending propositional logic with path quantifiers (A,E) and tense modalities (F, G, X, U).

CTL sais when something is inevitable or possible, but it hasn’t notion of strategy action nor agency (it’s a problem to model mechanisms…. and service-based applications too). ATL is intended to overcome these limitations. The basic expression is

meaning “coalition C can cooperate to ensure that . The idea is that, using coalitions, we can model who is going to achieve a property (a coalition can be an individual entity or even an empty set -modeling ‘nature’-). An example about social choice (voting) mechanism. Now, mechanisms can be validated.The logic can capture dependencies among agents, as stressfulness (all goals met), veto (j needs i to achieve its goal), mutual dependence (all agents are mutual dependence… veto relationship)

(note: but we can’t model actions yet, so I guess it isn’t useful for us)

A concrete application about social laws (normative systems). Objectives will be ATL formulae and mechanisms are behavioral constraints To avoid undesirable behaviors, we have to cut out some transitions. An effective social law . But compute this is a NP-hard problem. An example with the typical train organization in a tunnel. But you cannot model just the properties you want to avoid. The properties you want to preserve have to be modeled too in order to have system doing useful things.

But, what to do with non-compliance? The idea isto incentive compatibility and, to do this, we need preferences (a prioritized list of goal formulae). I like this idea: the utility of the agent comes from this list, from a worst (and weak) rule to the best (and stronger) rule. For instance, related with resources, have it assigned often and for a long time.

Towards the biological basis of cooperation
(Arcadi Navarro)

Talking about genome and human evolution. The interesting thing: the effects on social behavior.

After a very interesting introduction to genomic, begins trying to relate genetics with social behavior: because to cooperate can have some explanations in our genes (and this can be the explanation of why humans have  been a successful specie): genetic variability for behavioral traits is considerable. The problem is that this is very difficult to interpret. Fortunately, there are some genetics related with economic behavior that can be studied and replicated in labs.

Example: the ultimate game: people trend to make 50:50 offers and to reject less that 30% (not an reasonable decision from an economic point of view). But chimpanzees behaves as rational maximizes in an ultimatum game. Both species have evolve completely different behaviors. Why? we have to study this from a genetic perspective. -> agents playing games are as chimpanzees. And researchers are discovered that serotonin makes individuals to be more generous (just a joke: men have more serotonin than women). Or even between MZ twins, differences in the acceptance threshold in ultimatum game have been observed. Examples with more genes.

Measuring Strategic Uncertainly and Risk in Coordination-, entry-Games and lotteries with fMRI
(Rosemari Nagel)

Uncertainty can be classified as

• exogenous (risk): know the prob. of all possible states of the world (objective prob.)
• endogenous: in absence of endogenously given prob.;  -> strategic uncertainty (SU) e.g. outcomes depends on social interaction -games- (subjective prob.)

How brain solve individual or strategic uncertainty? Can we predict choices and brain activity in games?
Results: people behaves similarly in lottery and coordination games, but not in entry games. And the activity in the brain increases in lottery -> coordination -> entry. Some graphics about the different parts of the brain active while playing each type of game. Similar activity in entry games of risk lovers and risk averse people.

Summarizing, the entry games create mode strategic uncertainty as predicted by the nature of the mixed equilibrium which also involves levels of reasoning.

Como en otras ocasiones, se ha publicado la convocatoria para la formación de investigadores del CSIC. Es una beca pensada para alumnos de últimos cursos de carrera, para realizar una estancia en un centro del CSIC, supervisado por sus investigadores, entre los meses  de junio y septiembre.

Aquí tienes el listado con los temas posibles en los que trabajar. Ya puestos, te recomiendo los del IIIA, en Barcelona. Particularmente, el que lleva por título “Aplicación facebook para el estudio del castigo distribuido en entornos
virtuales” (JAE-INT-1594), dirigido por Jordi Sabater, y cuya descriptión te dejo aquí:

“En comunidades abiertas y distribuidas con un componente básico de interacción social entre agentes podemos observar los efectos emergentes de dichas interacciones.

En el marco de estudio de sistemas multiagentes, los diseñadores de agentes buscan incluir los mecanismos necesarios para que los agentes inteligentes sean capaces de interactuar de manera racional con los humanos. Los humanos, y como resultado emergente de sus interacciones, hemos desarrollado las conocidas “normas sociales” que restringen y coordinan nuestro comportamiento. Las normas sociales se caracterizan como normas que resuelven problemas de acción colectiva.

De la misma manera, los humanos hemos desarrollado mecanismos de imposición y mantenimiento de normas tal y como puede ser el castigo. Debido a las restricciones que nos imponen las sociedades virtuales, tanto el cumplimiento de las normas como la aplicación de dichos castigos, pueden ser ejecutados de manera distribuida. Los castigos directos y costosos han sido estudiados durante décadas por psicólogos y economistas, obteniendo resultados conclusivos acerca de este tipo de castigos.

Sin embargo, nosotros estamos interesados (para así aprovechar las ventajas que nos ofrecen los ambientes distribuidos) en el estudio del castigo de manera distribuida. En especial, los castigos indirectos distribuidos. Un claro ejemplo de dicho mecanismo es la reputación. La transmisión de rumores puede ser usada para aplicar un castigo, a quien sea que fuera necesario. Sin embargo, poco se conoce acerca de la latencia y dinámica de este tipo de castigo.

Para avanzar en el conocimiento de los sistemas distribuidos e indirectos de castigo, pretendemos construir una plataforma experimental que nos ayude a comprender el funcionamiento de un mecanismo tan usado como el de la transmisión de rumores.
Dicho proyecto implicará el desarrollo de una aplicación para la conocida plataforma social “Facebook”. Dicha aplicación se mostrará a los sujetos de estudio como un juego tipo colaborativo, donde se permitirá (y controlara como objeto de estudio) la transmisión de la información.”

El plazo termina el 6 de marzo.

Más información en la web de la  convocatoria.

Lo relevante empieza en el segundo 45 aprox. Y si no lo entiendes es que el jueves no estabas donde deberías

(Scrubs S04E13 Mi infarto de miocardio)

Es lo que voy a contar en ua charla de café, para explicar cómo Islander y Thomas encajan para modelar este tipo de sistemas (SES), aplicados al demostrador mWater, que es el que corresponde a nuestro grupo dentro del proyecto Agreeent Technologies.

Básicamente, he tratado de explicar brevemente las idesas de E. Ostrom, Premio Nobel de Economía del 2009, sobre el modelado de este tipo de sistemas y bajo qué condiciones las iniciativas de autoorganización pueden tener éxito. Juan Freire habla de lo mismo aplicado a urbanismo emergente.

Por si no hay copias  para todos o alguien de lo que no han asistido quiere descargar el documento, os lo dejo disponible aquí. Luego amplio este post para explicar alguna cosa más.

Y como siempre, cualquier comentario es bienvemido

Dentro de un rato vamos a hablar sobre la definición de agreement (acuerdo). Esto no es lo que vamos a usar, pero me apetecía hacerlo y colgarlo para recordarlo bien. Son cosas que ya habíamos comentado en una reunión en junio de 2009 y que no había escrito en ningún lado, así que casi se me olvida. Menos mal que Antonio copió (y sabe dónde lo tenía, que es más importante) lo que dije entonces.

Así que, para que no me vuelva pasar, os dejo aquí las 5 dimensiones que forman el acuerdo: contexto, participantes, creación, contrato y ejecución. Con cada una de ellas he añadido algunas consideraciones que se me iban ocurriendo. Seguro que ni son todas las que están ni están todas las que son, pero puede ser un comienzo.

Y como slideshare no copia las transiciones, lo dejo en un vídeo. Es sólo un minutín, así que no te aburirás mucho. También puedes descargar la versión en  PDF. Y, como siempre, te recuerdo que cualquier comentario será bien recibido.

(he cambiado el vídeo de sitio porque se cortaba el audio)

The International Symposium on Distributed Computing and Artificial Intelligence (DCAI 2010) is an annual forum that will bring together ideas, projects, lessons, etc.. associated with distributed computing, artificial intelligence and its applications in different themes. The workshop will be organized into CEDI 2010 that will be held at the Polytechnic University of Valencia in September 7-10th, 2010.

This symposium will be organized by the Biomedicine, Intelligent System and Educational Technology Reseach Group (BISITE) of the University of Salamanca. The technology transfer in this field is still a challenge and for that reason this type of contributions will be specially considered in this symposium. This conference is the forum in which to present application of innovative techniques to complex problems.

The artificial intelligence is changing our society. Its application in distributed environments, such as the Internet, electronic commerce, mobile communications, wireless devices, distributed computing, and so on is increasing and is becoming an element of high added value and economic potential, both industrial and research. These technologies are changing constantly as a result of the large research and technical effort being undertaken in both universities and businesses. The exchange of ideas between scientists and technicians from both academic and business areas is essential to facilitate the development of systems that meet the demands of today’s society.

DCAI 2010 is sponsored by the IEEE Systems Man and Cybernetics Society, Spain Section Chapter. The accepted papers included in DCAI 2010 proceedings (long papers, short papers and doctoral consortium papers) will be published by Springer Verlag in the Advances in Intelligent and Soft-Computing series of Springer. At least one of the authors will be required to register and attend the symposium to present the paper in order to include the paper in the conference proceedings.

(Read the complete Call for Papers)