I am an Assistant Professor at the computer science department of the University of Zürich. I received my PhD from the College of Computer & Information Science at Northeastern University advised by Alan Mislove and David Lazer.
Broadly, my work investigates a variety of content serving websites such as Search Engines, Online Stores, Job Search Sites or Freelance Marketplaces. In this quickly changing online ecosystem companies track users' every move and feed the collected data into big data algorithms in order to match them with the most interesting, most relevant content. Since these algorithms learn on human data they are likely to pick up on social biases and unintentionally reinforce them. In my PhD work I created a methodology called Algorithmic Auditing which tries to uncover the potential negative impacts of large online systems. Examples of such audits include examining the "Filter Bubble effect" on Google Search, online price discrimination or detecting inequalities in online labor markets.
For my detailed resume please see my CV.
And here is my PhD thesis (I promise it is easy to read!)
Join me as a Postdoc in my journey in Zurich! See the call here. If you have any questions about the application, don't hesitate to reach out!
Hiring a PhD student, see the call here. If you have any questions about the application, don't hesitate to reach out!
StackOverflow changes its reward system based on our paper! Feels amazing when our work results in real-world impact!
Starting a new job as an Assistant professor at the University of Zurich. Looking forward to building the Social Computing Group and eating a lot of cheese :)
Our paper about gender differences in participation on Stack Overflow was accepted to Empirical Software Engineering! PDF coming soon!
Three presentations and a best presentation award at the European Symposium on Societal Challenges in London.
Check out the awesome conference we organized on Gender and Success.
I was invited to give a keynote talk at CmpleNet in Dubrovnik. See my slides here.
Measuring Bias in Online Labor Markets
Labor economy has been through a lot of structural changes in the past years. People use various online services to find employment, advertise freelance services, collaborate on projects, outsource work, etc. These online sites offer innovative mechanisms for organizing employment or hiring processes and may alter many of the social forces known to cause social inequality in traditional labor markets. While policies in the traditional labor economy protecting people in the labor market have been developed over hundreds of years, we are at the early stages of this process in the online context. Paradoxically, while meaningful policy making requires a good understanding of the mechanisms that create or reinforce inequalities, without regulations reinforcing audits or some form of transparency, it is very difficult to learn about these systems. We combine a variety of methods, including online data collection and empirical analysis, online and field experiments, and survey base data collection.
Gender Bias on Stack Overflow
Programming is a valuable skill in the labor market, making the underrepresentation of women in computing an increasingly important issue. Online question and answer platforms serve a dual purpose in this field: they form a body of knowledge useful as a reference and learning tool, and they provide opportunities for individuals to demonstrate credible, verifiable expertise. Issues, such as male-oriented site design or overrepresentation of men among the site’s elite may therefore compound the issue of women’s underrepresentation in IT. In this project we audit the differences in behavior and outcomes between men and women on Stack Overflow, the most popular of these Q&A sites. We investigate how inequalities known from social sciences manifest in online communities and their root causes.
Simulating income inequality in Ride-Sharing
As they grow in popularity, ride-hailing and food-delivery services such as Uber, Lyft, Ola or Foodora are quickly transforming urban transportation ecosystems. Despite their potential to democratize the labor market, these services are often accused of fostering unfair working conditions and low wages. In this project, we investigate the effect of algorithm design decisions on wage inequality in ride-hailing platforms. Using a simulation approach, we can overcome the difficulties stemming from both the complexity of transportation systems and the lack of data and algorithmic transparency. We calibrate our model based on empirical data, including conditions about locations of drivers and passengers, traffic, the layout of the city, and the algorithm that matches requests with drivers. Then we evaluate the output of the simulation under various external conditions.
Gender Differences in Participation and Reward on Stack Overflow
Empirical Software Engineering, 2019
And Now for Something Completely Different: Visual Novelty in an Online Network of Designers
Proceedings of the 10th ACM Conference on Web Science (WebSci'18), Amsterdam, May, 2018.
Investigating the Impact of Gender on Rank in Resume Search Engines
In Proceedings of ACM Human Factors in Computing Systems (CHI 2018). Montreal, Canada, April, 2018.
Political Fact-Checking on Twitter: When Do Corrections Have an Effect?
In the journal of Political CommunicationFair Sharing for Sharing Economy Platforms
In Proceedings of the FATREC Workshop on Responsible Recommendation (colocated with RecSys 2017), Como, Italy, August 2017.Why Do Men Get More Attention? Exploring Factors Behind Success in an Online Design Community
Proceedings of the 11th International AAAI Conference on Weblogs and Social Media (ICWSM'17) Montreal, May, 2017.Bias in Online Freelance Marketplaces: Evidence from TaskRabbit and Fiverr
Proceedings of the 20th ACM Conference on Computer-Supported Cooperative Work and Social Computing (CSCW 2017), Portland, OR, February, 2017.Location, Location, Location: The Impact of Geolocation on Web Search Personalization
Proceedings of the 15th ACM Internet Measurement Conference (IMC'15), Tokyo, Japan, October 2015.Measuring Price Discrimination and Steering on E-commerce Web Sites
Proceedings of the 14th ACM/USENIX Internet Measurement Conference (IMC'14), Vancouver, Canada, November 2014.Get Back! You Don't Know Me Like That: The Social Mediation of Fact Checking Interventions in Twitter Conversations
Proceedings of the 8th International AAAI Conference on Weblogs and Social Media (ICWSM'14), Ann Arbor, MI, June 2014Measuring Personalization of Web Search
Proceedings of the 22nd International World Wide Web Conference (WWW'13), Rio de Janeiro, Brazil, May 2013.Tweetin' in the Rain: Exploring societal-scale effects of weather on mood (Poster Paper)
Proceedings of the 6th International AAAI Conference on Weblogs and Social Media (ICWSM'12), Dublin, Ireland, June 2012.
Posters and presentations
Power of Digital Research Roundtable
International Communication Association Conference, Fukuoka, Japan, 2016
Bias in Online Freelance Marketplaces
In 2nd Annual International Conference on Computational Social Science, Evanston, IL, June, 2016.Get Back! You Don't Know Me Like That: The Social Mediation of Fact Checking Interventions in Twitter Conversations
Proceedings of the 8th International AAAI Conference on Weblogs and Social Media (ICWSM'14), Ann Arbor, MI, June 2014Behavioral Responses to Fact-Checking Interventions in Online Social Networks
Sunbelt 2014, St. Petersburg FL, Feb. 2014Mitigating Sybil attacks on content rating systemsSOSP 2011Measuring and predicting sentiment on Twitter
Discrimination in Online Freelance Markets
- Researchers find racial, gender bias in online freelance marketplaces News@Northeastern,
- Data shows race and sex bias is costly for gig economy workers at startups like TaskRabbit Mic,
- Studies Show Racial and Gender Discrimination Throughout the Gig Economy
Is the Gig Economy Rigged?
MIT Tech Review,
No one in control: The algorithms that run our lives
Do companies charge online shoppers different prices? [Video Interview/ph
CBS Evening News
Online shopping yields different prices, results, says Northeastern study
The Boston Globe
Why You Can't Trust You're Getting the Best Deal Online
The Wall Street Journal
You're Being Watched: Online Stores Know Your Habits
Holiday Travel Saving Secrets: Beware of Price Steering With Video]
ABC News (Broadcast on Good Morning America)
Study: Online Price Discrimination Is Real With Video]
If you use a Mac or an Android, e-commerce sites may be charging you more
The Washington Post
Buyer beware, online shopping prices vary user to user
E-commerce sites personalize search results to maximize profits
How to Beat Online Price Discrimination
Shopping Online? Beware Of Price Discrimination
WBUR Radio Boston
How To Beat Online Price Discrimination
Why Some People Pay More Than Others When Shopping Online
The Huffington Post
Travelocity apparently saves the best deals for iOS shoppers
Study Will Make You Question Prices on Travel Websites
Want the best price online? Good luck with that.With Podcast Interview]
Online Personalization Means Prices Are Tailored To You, Too With Podcast Interview]
Guess What? You Aren't Always Seeing The Lowest Price, Study Says
How You Shop Online Changes The Prices You See
Fast Company Exist
The sneaky practice of price-steering: How e-commerce websites charge some customers more for the same item
Study: Home Depot shows smartphone users more expensive items online
Atlanta Business Chronicle
Study: some online shoppers pay more than others
Google's Searches Narrowing Our Experience
The Saturday Post,
Védekezni ellene nemigen tudunk” - Hannák Ancsa kutató az online adatgyűjtésről
Oct 17, 2015
Nov 7, 2013
Department of Informaticshannak@ifi.uzh.ch
University of Zurich
+41 44 635 43 18