Econophysics and Sociophysics

Lecture IV

R. Mansilla

CEIICH, UNAM

Just a little of History…again

The founding fathers of social sciences have always had a clear idea of the importance of systematizing their knowledge of social groups based on the concepts and principles of Physics, which had been remarkably successful in predicting their phenomena under study. This research program were not concluded basically because social phenomena have a much higher complexity compared to the physical phenomena and because the lack of computing power needed to build realistic models. Berry, B. J. L., Kiel, L. D., Elliot, E., Adaptive agents, intelligence and emergent human organization: Capturing complexity through agent-based modeling, Proceedings of the National Academy of Science of the USA, 99, pp. 7187, 2002. We want to expose as exceptional examples of such efforts a couple of researchers well known in the branch of Social Sciences.

Thomas Hobbes (1588-1679)

Thomas Hobbes is best known for his political thought, and deservedly so. His vision of the world is strikingly original and still relevant to contemporary politics. His main concern is the problem of social and political order: how human beings can live together in peace and avoid the danger and fear of civil conflict.   His theoretical work began after reading an edition of The Elements of Euclides. He became fascinated with the axiomatic order of the theory and tried to apply that to social phenomena. Of immediate embarked on a long journey to Padua just to know and be able to talk to Galileo.

A Quetelet (1796 - 1874)

After receiving this doctorate he was appointed to the chair of elementary mathematics at the Athenaeum in Brussels. In February 1820 he was elected to the Royal Belgium Academy of Science and greatly invigorated the Academy over the following years. In December 1823, he went to Paris to study astronomy at the Observatory there. He was impressed by the work of Laplace on probability and its applications to the statistics of the French Empire. He thought on the possibility of use it for the study of social phenomena. His biggest work is a book entitled Social Physics.

Robert Alxelrod

He is best known for his interdisciplinary work on the evolution of cooperation which has been cited in more than five hundred books and four thousand articles. Current research interests include complexity theory, especially agent-based modeling.

The Evolution

of Cooperation

A seminal paper

The Sznajd model is a one-dimensional chain of spins and a rule of evolution defined as follows:

SiSi−1 Si+1

Considering only these two rules, one of the following configurations is attained

Therefore it should necessary add an element of randomization. After each iteration a group of spins are chosen at random and flips the orientation. These flipping is made also randomly.

Avalanches are observed similar to those reported first by P. Bak in the model of self organizing criticality. The variable to study here was the time between changes in orientation of the spins.

Serge Galam Center for Research in Applied Epistemology

Ècole Polytechnique Paris

•  Predicting victory for the 'NO' vote on the European Constitution.

•  Prediction of the scenary where the party of J. F. Le Pen would be able to achieve the win in a democratic form.

•  Predicting elections "50-50" for instance A- Gore and G. W. Bush. He also studied the Mexican 2006 presidential election.

•  Convergence to an equilibrium. http://arxiv.org/abs/physics/0703095

Basic objections

•  Assumes that there is independence in contacts between people. •  Agents are uniformly susceptible to the opinions of their neighbors.

•    Ignores social networks.

•  Does not take into account the movement of the population.

•  Mass media of comunication are considered in the models.  We decided to develop a model in which there were three political parties, The independence of decisions were removed, namely, the agents discuss their views with members of their household, co-workers or felows in their schools. Note that a three party election could be simulated with a Potts model.

8.348.345

8.358.355

8.368.365

8.378.375

x 104

8.168.18

8.28.22

8.248.26

8.288.3

x 104

8.36

8.38

8.4

8.42

8.44

8.46

8.48

x 104

A jewel

12

τ n = τ1n−b

Improvised Explosive Devices

FIN