Here I collect the most recent important news about my work.

I moved from Groningen to Karlsruhe

posted Nov 10, 2020, 3:14 AM by Michael Maes

Since November 2020, I am professor of sociology at the KIT, a technical university in Karlsruhe, Germany.

Leaving Groningen was a difficult step. I love the city, the Faculty of Behavioral and Social Sciences, the Department of Sociology, and the ICS graduate school. There are many great friends and colleagues that I miss dearly. Thanks for making Groningen my second home.

My new chair is part of the Institute of Technology Futures, which is an interdisciplinary research institute focussing on the effects of technology on humans, societies, and the environment. In addition, I am the scientific director of the Methods laboratory of KIT's House of Competence
My teaching will focus on undergraduate sociology courses. In addition, I will offer courses at the House of Competence and the Institute of Technology Futures.

The KIT provides generous funding for empirical and theoretical research into the complexity of online communication systems. In addition, I will continue my work on cooperation and coordination in networks.

Workshop on validating models of opinion polarization at EUROCSS

posted Sep 2, 2019, 11:05 PM by Michael Maes

We had a great workshop on Validating Models of Opinion Polarization in the Digital Era at the European Symposium Series on Societal Challenges in Computational Social Science. Thanks to my coorganizers, Andreas Flache and Marijn Keijzer and many thanks to all contributors. The slides of the talks can be downloaded from the workshop website.

ORA Grant for empirical and theoretical research on social influence in networks

posted Nov 4, 2018, 5:35 PM by Michael Maes

We have received funding for our project “ToRealSim: Towards realistic computational models of social influence dynamics”. The grant has a volume of 1.2 million Euro. 63 out of initially 294 pre-proposals were admitted to the full-proposal stage, of which 16 proposals received a grant.   

Summary of the project: Recently, many societies shifted towards more polarization and volatility in opinions, for example in attitudes about immigration or climate policy. The project ToRealSim (Towards realistic computational models of social influence dynamics) has the ambition to improve understanding of these dynamics by focusing on the complex micro-macro interactions that may bring them about. Opinion dynamics will be studied as possible unintended results of local yet interdependent social influence processes in large populations. In a combined effort of reseach teams from the Netherlands (U Groningen), UK (U Manchester & Leicester), Germany (Jacobs U, Bremen) and France (LISC, Aubiere), computational agent-based models will be theoretically extended, empirically calibrated with data from experiments and social network studies; and tested against observed opinon dynamics in immigration- and climate-related issues, using in particular a range of large-scale cross-country survey and panel data-sets. Models will further be used to study policy implications.

Communication in Online Social Networks Fosters Cultural Isolation

posted Nov 4, 2018, 5:21 PM by Michael Maes

Together with Marijn Keijzer, and Andreas Flache, I published a paper in Complexity. You can find it here.

Abstract: Online social networks play an increasingly important role in communication between friends, colleagues, business partners, and family members. This development sparked public and scholarly debate about how these new platforms affect dynamics of cultural diversity. Formal models of cultural dissemination are powerful tools to study dynamics of cultural diversity but they are based on assumptions that represent traditional dyadic, face-to-face communication, rather than communication in online social networks. Unlike in models of face-to-face communication, where actors update their cultural traits after being influenced by one of their network contacts, communication in online social networks is often characterized by a one-to-many structure, in that users emit messages directly to a large number of network contacts. Using analytical tools and agent-based simulation, we show that this seemingly subtle difference can have profound implications for emergent dynamics of cultural dissemination. In particular, we show that within the framework of our model online communication fosters cultural diversity to a larger degree than offline communication and it increases chances that individuals and subgroups become culturally isolated from their network contacts.

New working paper on the complexity approach to sociology

posted Feb 24, 2018, 6:33 AM by Michael Maes   [ updated Feb 24, 2018, 6:36 AM ]

I just uploaded a new article to the SSNR. You can download it here.

In the sociological literature, there is an increasing number of contributions with an approach inspired by the field of complexity science. Here, I identify important commonalities between typical sociological research problems and phenomena studied by complexity researchers, arguing that both fields focus on macro-phenomena that emerge from the behavior of micro-entities. Next, I compare the approach of complexity science with prominent methodological approaches to sociology. I argue that complexity research shares core principles with both structural and structural-individualistic approaches to sociology. However, in particular the approach put forward by analytical sociologists overlaps on the crucial dimensions with complexity research. I also discuss differences between complexity research and the contemporary sociological mainstream, identifying aspects where contemporary sociological research can profit from adopting a complexity perspective. Arguing that large parts of the sociological literature seem to have lost focus on sociology’s original contribution to the understanding of human behavior, I frankly formulate six recommendations on how to refocus contemporary sociological research.  


posted Feb 22, 2018, 9:14 AM by Michael Maes   [ updated Feb 22, 2018, 9:19 AM ]

"Piled Higher and Deeper" by Jorge Cham

I got promoted and got tenure. Thanks RuG and thanks to everyone who supported me in the past years. 

The comic is from:  "Piled Higher and Deeper" by Jorge Cham (

Paper published in Sociological Methods and Research

posted Jul 20, 2017, 2:46 PM by Michael Maes   [ updated Nov 30, 2017, 2:30 AM ]

Great news. Sociological Methods and Research accepted a joint paper with Dirk Helbing. In this paper, we report results of two experiments testing hypotheses about the effects of noise on the micro-level on macro-outcomes.

While there is no doubt that human behavior follows certain patterns, there is also obvious that humans also often deviate from these patterns. Most social scientists do not pay attention to these deviations. However, many theories predict that deviations from the behavioral patterns of individuals can have decisive impact on the behavior of social collectives even when deviations are rare and random. In this paper, we tested this notion, showing that macro-deviations can have macro-effects and that it can be accurately predicted when deviations matter.

You can download the online-first paper here.

Title: Random deviations improve micro-macro predictions. An empirical test.

Abstract: Many sociological theories make critically different macro-predictions when their micro-assumptions are implemented stochastically rather than deterministically. Deviations from individuals’ behavioral patterns described by micro-theories can spark cascades that change macro-outcomes, even when deviations are rare and random. With two experiments, we empirically tested whether macro-phenomena can be critically shaped by random deviations. 96 percent of participants’ decisions were in line with a deterministic theory of bounded rationality. Despite this impressive micro-level accuracy, the deterministic model failed to predict the observed macro- outcomes. However, a stochastic version of the same micro-theory largely improved macro-predictions. The stochastic model also correctly predicted the conditions under which deviations mattered. Results also supported the hypothesis that non-random deviations can result in fundamentally different macro-outcomes than random deviations. In conclusion, we echo the warning that deterministic micro-theories can be misleading. Our findings show that taking into account deviations in sociological theories can improve explanations and predictions. 

Social influence and opinion polarization on the Internet

posted Jun 20, 2017, 11:35 AM by Michael Maes   [ updated Jun 20, 2017, 11:36 AM ]

We finished a working paper summarizing findings of two field experiments and a natural experiment on social influence and processes of opinion polarization on the Internet.  You can find the working paper here 

Title: Micro Influence and Macro Dynamics of Opinions 

Abstract: There is ongoing debate about the effects of social influence on the micro level and resulting opinion polarization on the macro level. We propose a general model that captures prominent, competing micro-level theories of social influence. Conducting a lab-in-the-field experiment, we observe that individual opinions shift linearly towards the mean of the distribution of other opinions. With this finding, we predict the macro-level opinion dynamics resulting from social influence. We test our predictions using data from a second lab-in-the-field experiment and find that social influence reduces opinion polarization. We corroborate these findings with additional field data.    

German podcast features my research on nudging and cascades

posted Sep 20, 2016, 7:27 AM by Michael Maes   [ updated Sep 20, 2016, 7:35 AM ]

The Braincast podcast featured my research on nudging and cascades of norm violation in social networks. In only 20 minutes, the podcast explains what sociology is about, summarizes my research with Karl-Dieter Opp on norm violation in networks, and debates problems of nudging.

You can listen to the podcast (in German) here. The paper is published here

The following animation movie provides an impression of the dynamics that we studied in our paper.

Two experiments do not support the negative-influence assumption

posted Jun 23, 2016, 3:10 AM by Michael Maes   [ updated Jun 23, 2016, 3:11 AM ]

Together with Károly Takács, and Andreas Flache I published results from two laboratory experiments testing the assumption that individuals tend to increase opinion differences to disliked others (negative influence). The paper is here.

Both classical social psychological theories and recent formal models of opinion differentiation and bi-polarization assign a prominent role to negative social influence. Negative influence is defined as shifts away from the opinion of others and hypothesized to be induced by discrepancy with or disliking of the source of influence. There is strong empirical support for the presence of positive social influence (a shift towards the opinion of others), but evidence that large opinion differences or disliking could trigger negative shifts is mixed. We examine positive and negative influence with controlled exposure to opinions of other individuals in one experiment and with opinion exchange in another study. Results confirm that similarities induce attraction, but results do not support that discrepancy or disliking entails negative influence. Instead, our findings suggest a robust positive linear relationship between opinion distance and opinion shifts.

1-10 of 25