Johannes Wachs

Assistant Professor (non-TT)
Vienna Uni. of Economics and Business
Complexity Science Hub Vienna

About Me

I am an assistant professor (non-TT) at the Institute for Information Business of the Vienna University of Economics and Business (WU Wien). I am also affiliated with the Complexity Science Hub. My research examines social, technical, and economic networks and their effects on society.

Previously I was a postdoc of Markus Strohmaier at the Chair for Computational Social Sciences and Humanities at RWTH Aachen. My dissertation, supervised by János Kertész at Central European University, was on the application of network methods to the study of corruption. During my PhD I was a visitor at the Oxford Internet Institute, the Hertie School of Governance, and the Hungarian Academy of Sciences.

News

October 2020: Our team won the IMF Anti-Corruption Challenge!
October 2020: New preprint on user development on Stack Overflow.
August 2020: Janos Kertesz and I wrote a comment for Nature Reviews Physics on applying network science to the study of economic crimes like corruption: [Link].

Publications

Complexity science approach to economic crime [Link]

János Kertész and Johannes Wachs
Nature Reviews Physics, 2020.

Corruption and the Network Structure of Public Contracting Markets across Government Change [Link]

Mihály Fazekas and Johannes Wachs
Politics and Governance, 2020.

Corruption risk in contracting markets: a network science perspective. [Link]

Johannes Wachs, Mihály Fazekas, and János Kertész
International Journal of Data Science and Analytics, 2020.

A network approach to cartel detection in public auction markets. [Link]

Johannes Wachs and János Kertész
Scientific Reports, 2019.

Gender Differences in Participation and Reward on Stack Overflow. [Link]

Anna May, Johannes Wachs, Aniko Hannak
Empirical Software Engineering, 2019.

Social capital predicts corruption risk in towns. [Link]

Johannes Wachs, Taha Yasseri, Balázs Lengyel, János Kertész
Royal Society Open Science, 2019.

The Role of Novelty in Securing Investors for Equity Crowdfunding Campaigns. [Link]

Emőke-Ágnes Horvát, Johannes Wachs, Rong Wang, Aniko Hannak
AAAI Conference on Human Computation and Crowdsourcing (HCOMP), 2018.

And Now for Something Completely Different: Visual Novelty in an Online Network of Designers. [Link]

Johannes Wachs, Balint Daroczy, Aniko Hannak, Katinka Pall, Christoph Riedl
Proceedings of the 10th ACM Conference on Web Science (WebSci), 2018.

Why Do Men Get More Attention? Exploring Factors Behind Success in an Online Design Community. [Link]

Johannes Wachs, Aniko Hannak, Andras Voros, Balint Daroczy
Proceedings of the 11th International AAAI Conference on Weblogs and Social Media (ICWSM), 2017.

Preprints

From Asking to Answering: Getting More Involved on Stack Overflow. [Link]

Timur Bachschi, Aniko Hannak, Florian Lemmerich, Johannes Wachs
arXiv:2010.04025, 2020

How Gamification Affects Software Developers: Cautionary Evidence from a Quasi-Experiment on GitHub. [Link]

Lukas Moldon, Markus Strohmaier, Johannes Wachs
arXiv:2006.02371, 2020

The Effects of Gender Signals and Performance in Online Product Reviews. [Link]

Sandipan Sikdar, Rachneet Singh Sachdeva, Johannes Wachs, Florian Lemmerich, Markus Strohmaier
arXiv:2001.09955, 2020

Inequality is rising where social network segregation interacts with urban topology. [Link]

Gergő Tóth, Johannes Wachs, Riccardo Di Clemente, Ákos Jakobi, Bence Ságvári, János Kertész, Balázs Lengyel
arXiv:1909.11414, 2019

No country for asylum seekers? How short-term exposure to refugees influences attitudes and voting behavior in Hungary. [Link]

Theresa Gessler, Gergő Tóth, Johannes Wachs
SocArxiv, DOI: 10.31235/osf.io/qgpve, 2019.

Teaching

Applied Data Science: Computational Social Science, Vienna University of Economics and Business Winter Semester 2020-21
Research Praktikum, RWTH Aachen Winter Semester 2019-20
Social Data Science, course instructor, RWTH Aachen Winter Semester 2019-20
Social Networks, course instructor, RWTH Aachen Summer Semester 2019
Using Big Data for social science research, teaching assistant, CEU Spring 2017
Data Mining, course instructor, AIT Fall 2016
Scientific Python, teaching assistant, CEU Fall 2016, 2017

Selected Student Theses:
--- Lukas Moldon, Sending signals in open source: Evidence from a natural experiment. Bachelor's Thesis, RWTH Aachen, 2020. [PDF]
--- Timur Bachschi, From Asking to Answering: Social and Structural Aspects of Contributing to Stack Overflow. Bachelor's Thesis, RWTH Aachen, 2020. [PDF]

Education

PhD Network Science, summa cum laude, Central European University (2019)
MS Applied Mathematics with distinction, Central European University (2012)
BS Mathematics, BS Economics, cum laude, Tulane University (2009)

Contact

johanneswachs at gmail dot com