My dissertation consists of three main projects and several side projects. Below I outline the scope and the purpose of several projects.

Project 1: Awareness of the political alignment of one's own Twitter network.

In this project, I utilize the results of a survey conducted by YouGov and provided by Pablo Barberá and colleagues in order to evaluate Twitter user's awareness of the political alignment of their Twitter friends. I complimented the survey data with data retrieved from the Twitter API in an effort that included the retrieval of Twitter profile information of 246.693 Twitter users. We find that Twitter users' perceptions are biased by a False Consensus Effect and that political knowledge helps identify the most frequent political group among one's Twitter friends. This project is the first to analyze the perceptions about the political constitution of one's Twitter friends and employs a novel approach by utilizing the procedure of Pablo Barberá's Tweetscores.

Project 2: Awareness of own Twitter activity and implications of misreporting for social science.

In this project, I employed a survey via several platforms (Respondi, JobBoy, Twitter Ads) in order to compare the quality of the self-reported Twitter activity. I compared survey responses to questions regarding one's Twitter activity with observed activity. Results suggest that people generally misreport their own activity and these results have implications for the treatment of survey responses in general. Additionally, I find a significant impact of intrinsic motivation for the quality of survey responses and I discuss the potential remedies to this problem of misreporting.

Project 3: Awareness of the political alignment of Twitter networks and the perceived need for changes to these networks.

In this project, I analyze the ability to detect political slant in Twitter networks and the normative evaluations of these slants by distributing a vignette experiment to Amazon Mechanical Turk workers.

Side Project 1: Towards a classifier for political ideology of German Twitter users.

In a joint project with Marius Sältzer from the University of Mannheim I am working towards a classifier that enables the classification of German Twitter users' political ideology. The work includes the analysis of more than 8 Mio Followers of German political elites and news outlets and encompasses a methodology that is similar to the procedure of Pablo Barberá's Tweetscores.

Side Project 2: `Fine People on Both Sides': How the Sharing of Images Shapes Contentious Politics.

This project is joint work with Karsten Donnay, Zachary Steinert-Threkeld and others and includes analyses of 806,937 images shared on Twitter around the events of Charlottesville in 2018.