Section: New Results
An Experimental Protocol for Analyzing the Accuracy of Software Error Impact Analysis 
In software engineering, error impact analysis consists in predicting the software elements (e.g. modules, classes, methods) potentially impacted by a change. Impact analysis is required to optimize the testing effort. In this paper we present a new protocol to analyze the accuracy of impact analysis. This protocol uses mutation testing to simulate changes that introduce errors. To this end, we introduce a variant of call graphs we name the ”use graph” of a software which may be computed efficiently. We apply this protocol to two open-source projects and correctly predict the impact of 30
A Learning Algorithm for Change Impact Prediction: Experimentation on 7 Java Applications 
Change impact analysis consists in predicting the impact of a code change in a software application. In this paper, we take a learning perspective on change impact analysis and consider the problem formulated as follows. The artifacts that are considered are methods of object-oriented software; the change under study is a change in the code of the method, the impact is the test methods that fail because of the change that has been performed. We propose an algorithm, called LCIP that learns from past impacts to predict future impacts. To evaluate our system, we consider 7 Java software applications totaling 214,000+ lines of code. We simulate 17574 changes and their actual impact through code mutations, as done in mutation testing. We find that LCIP can predict the impact with a precision of 69
Spoken Dialogue Systems
Human-Machine Dialogue as a Stochastic Game 
In this paper, an original framework to model human-machine spoken dialogues is proposed to deal with co-adaptation between users and Spoken Dialogue Systems in non-cooperative tasks. The conversation is modeled as a Stochastic Game: both the user and the system have their own preferences but have to come up with an agreement to solve a non-cooperative task. They are jointly trained so the Dialogue Manager learns the optimal strategy against the best possible user. Results obtained by simulation show that non-trivial strategies are learned and that this framework is suitable for dialogue modeling.