Logic List Mailing Archive

PhD student position in Logic-based models of trust, Toulouse (France)

Thesis subject:
Logic-based model of trust in composed services

Supervisors:
Guillaume Feuillade, Andreas Herzig
IRIT-LILaC, Toulouse, France

Description:
In some recent works (Lorini and Demolombe 2008, Lorini and Demolombe 2009, 
Herzig et al. 2010), in the framework of the ANR ForTrust project 
(http://www.irit.fr/ForTrust, 2007-2010), a logical model of trust has been 
devised. In this model the main constituents of trust conceived as a mental 
attitude are formally characterized and its logical properties are studied. In 
accordance with the socio-cognitive theory of trust proposed by (Castelfranchi 
and Falcone 1998, Falcone and Castelfranchi 2001), in the ForTrust model, trust 
is defined as a belief of the truster about certain properties of the trustee 
which are relevant for the achievement of a goal of the truster. Among these 
properties, there are the trustee's skills and abilities, and the trustee's 
willingness to perform a given action for the achievement of the truster's 
goal. However, the ForTrust model is limited since it only considers an agent's 
trust in the atomic action of another agent and does not apply to trust in 
multi-agent plans where the elements in the plan are atomic actions of 
different agents.

The aim of this research project is to extend the ForTrust logic-based model in 
order to obtain a new logic-based model of trust which allows characterizing 
trust in multi-agent plans and, consequently, trusting in composed e-services. 
In this new model, trust in a complex e-service will be defined in a 
compositional way from trust in the components of that e-service. The model 
will also clarify the relationships between trust in complex e-services and 
security properties like privacy, integrity and availability. For instance, the 
model will clarify the conditions under which an agent's belief about certain 
properties of the e-service related to security (e.g. whether the e-service 
preserves confidentiality and/or integrity of information) supports the agent's 
trust in the complex e-service. The model will thus allow to express a 
composition problem where a goal must be achieved using the available 
e-services under trust assumptions, the composition problem translating into a 
satisfiability problem in the logic-based model of trust. This will allow 
extending existing service composition methods by adding the trust component in 
the equation.

The thesis is funded for 3 years by the ANR PIMI project (2010-2013) in which 
the LILaC group of IRIT takes part and that is lead by e-Citiz.

Application:
Please send applications to feuillad@irit.fr and herzig@irit.fr.