Research Projects


Theoretical Basis for Opinion Dynamics

        In this project, we investigate the use of Bayesian solutions as a basis for creating new models in Opinion Dynamics. By using subjective probabilities to model the opinions of the agents in an artificial society, we obtain a theoretical framework for proposing models for different circumstances. This provides a powerful tool for developing new descriptions as well as improving existing ones, with the additional benefit that the agents can be described as endowed with a bounded rationality (supported by grants from FAPESP and CNPq).

This line of work has also allowed the modeling of emergence of extreme opinions. A very interesting application is the study of the circumstances that increase or decrease extreme opinions in a society. This has attracted some media attention (see the links in the Media section).

   Social Effects on Science

    The aim of this research is to investigate the consequences that social influences can have on the reliability of scientific knowledge. In order to better understand how different behaviors can influence or not the possibility that scientists will choose a better description, we use agent-based models as a tool to explore possible circumstances where a majority opinion in a scientific artificial society might not correspond to the best choice.

    Correlations in Financial Time Series

An important part of the correlation matrix for temporal series of many assets can be explained as noise. In order to model this effects, we are studying a statistical description that allows for a simple introduction of non-stationarity and that fits the eigenvalues of the correlation matrix reasonably well. This model has, as a limit case, a Random Matrix description of the problem, while preserving the existence of non-random eigenvalues.

Diffusion of Innovations

By using the techniques of Opinion Dynamics, we investigate how an innovation will spread through a society of artificial agents. This has interesting applications in the dissemination of new ideas as well as the adoption of new products.

    Rationality and Heuristics - Normative Theories and 
Human Thinking 

People do not obey to normative theories of rationality when making decisions. However, the observed behavior when dealing with uncertainty can be described as an approximation to a Bayesian inference.  We aim to better understand the requirements for a rational behavior, from a Bayesian point of view and to understand what kinds of heuristics people use to make decisions when faced with uncertainty.

Starting Projects

    Information Theory and Music

By applying techniques of Information Theory, we plan to develop new methods of musical analysis and make contributions to the problem of recomposing missing parts of musical works.

     Citation Dynamics

Scientific citations are supposed to represent quality and to indicate who were the first scientists responsible for a given discovery. In this work, we propose models to explore the dynamics of how works get cited, with a special interest in the problem of earlier works that remain unknown for quite a while.