Selected Publications

2021

[HT 2021] What Is Unclear? Computational Assessment of Task Clarity in Crowdsourcing. Zahra Nouri, Ujwal Gadiraju, Gregor Engels, Henning Wachsmuth. In Proceedings of the ACM Conference on Hypertext and Social Media (HT 2021). [PDF]
[CSCW 2021] Using Worker Avatars to Improve Microtask Crowdsourcing. Sihang Qiu, Alessandro Bozzon, Max V. Birk, Ujwal Gadiraju. In Proceedings of the ACM on Human-Computer Interaction (CSCW 2021). [PDF]
[NAACL 2021] Towards Benchmarking the Utility of Explanations for Model Debugging. Maximilian Idahl, Lijun Lyu, Ujwal Gadiraju, Avishek Anand. In Proceedings of TrustNLP: First Workshop on Trustworthy Natural Language Processing Colocated with the Annual Conference of the North American Chapter of the Association for Computational Linguistics. [PDF]
[SIGIR 2021] This Is Not What We Ordered: Exploring Why Biased Search Result Rankings Affect User Attitudes on Debated Topics Tim Draws, Nava Tintarev, Ujwal Gadiraju, Alessandro Bozzon and Benjamin Timmermans. In Proceedings of the 44th International ACM SIGIR Conference on Research and Development in Information Retrieval (SIGIR 2021). [PDF]
[Web Science 2021] Improving Reactions to Rejection in Crowdsourcing Through Self-Reflection Tom Edixhoven, Sihang Qiu, Lucie Kuiper, Olivier Dikken, Gwennan Smitskamp and Ujwal Gadiraju. In Proceedings of the 13th ACM Web Science Conference (WebSci 2021). [PDF]
[CUI@CHI 2021] How Do User Moods Affect Perceived Delays in Crowd-Powered Conversational Interactions? Tahir Abbas, Ujwal Gadiraju, and Panos Markopoulos. In Proceedings of the Workshop at the 2021 ACM CHI Conference – Let’s Talk About CUIs: Putting Conversational User Interface Design Into Practice (CUI@CHI 2021). [PDF]
[UMAP 2021] How Do User Opinions Influence Their Interaction With Web Search Results? Luyan Xu, Mengdie Zhuang, and Ujwal Gadiraju. In Proceedings of the 29th ACM Conference on User Modeling, Adaptation and Personalization (UMAP 2021). [PDF]
[UMAP 2021] Second Chance for a First Impression? Trust Development in Intelligent System Interaction. Suzanne Tolmeijer, Ujwal Gadiraju, Ramya Ghantasala, Akshit Gupta, and Abraham Bernstein. In Proceedings of the 29th ACM Conference on User Modeling, Adaptation and Personalization (UMAP 2021). [PDF]
[IRJ 2021] Topic-independent Modeling of User Knowledge in Informational Search Sessions. Ran Yu, Rui Tang, Markus Rokicki, Ujwal Gadiraju, and Stefan Dietze. Information Retrieval Journal. [PDF]
[ECIR 2021] How Do Active Reading Strategies Affect Learning Outcomes in Web Search? Nirmal Roy, Manuel Valle Torre, Ujwal Gadiraju, David Maxwell, and Claudia Hauff. In Proceedings of the 43rd annual BCS-IRSG European Conference on Information Retrieval (ECIR 2021). [PDF]
[CHIIR 2021] Note the Highlight - Incorporating Active Reading Tools in a Search as Learning Environment. Nirmal Roy, Manuel Valle Torre, Ujwal Gadiraju, David Maxwell, and Claudia Hauff. In Proceedings of the 6th ACM SIGIR Conference on Human Information Interaction and Retrieval (CHIIR 2021). [PDF]

2020

[Crowd Science 2020] What Can Crowd Computing Do for the Next Generation of AI Systems? Ujwal Gadiraju and Jie Yang. In Proceedings of the Crowd Science Workshop: Remoteness, Fairness, and Mechanisms as Challenges of Data Supply by Humans for Automation at NeurIPS 2020. [PDF]
[Crowd Science 2020] Conversational Crowdsourcing. Sihang Qiu, Ujwal Gadiraju, Alessandro Bozzon, and Geert-Jan Houben. In Proceedings of the Crowd Science Workshop: Remoteness, Fairness, and Mechanisms as Challenges of Data Supply by Humans for Automation at NeurIPS 2020. [PDF]
[IWILDS 2020] Conversational Interfaces for Search As Learning. Sihang Qiu, Alessandro Bozzon, Ujwal Gadiraju. In Proceedings of the 1st International Workshop on Investigating Learning During Web Search (IWILDS 2020) at CIKM 2020. [PDF]
[CSCW 2020] TickTalkTurk: Conversational Crowdsourcing Made Easy. Sihang Qiu, Ujwal Gadiraju, Alessandro Bozzon. In Proceedings of the ACM on Human-Computer Interaction (CSCW 2020). [PDF]
[BIAS 2020] Assessing Viewpoint Diversity in Search Results Using Ranking Fairness Metrics. Tim Draws, Nava Tintarev, Ujwal Gadiraju, Alessandro Bozzon, Benjamin Timmermans. In Proceedings of the 1st Workshop on Bias and Fairness in AI at the European Conference on Machine Learning and Principles and Practice of Knowledge Discovery in Databases (ECML-PKDD 2020). [PDF]
[HCOMP 2020] Impact of Algorithmic Decision Making on Human Behavior: Evidence from Ultimatum Bargaining. Alexander Erlei, Franck Awounang Nekdem, Lukas Meub, Avishek Anand, Ujwal Gadiraju. In Proceedings of the 8th AAAI Conference on Human Computation and Crowdsourcing (HCOMP 2020). [PDF]
[HCOMP 2020] Trainbot: A Conversational Interface to Train Crowd Workers for Delivering On-Demand Therapy. Tahir Abbas, Vassilis-Javed Khan, Ujwal Gadiraju, Panos Markopoulos. In Proceedings of the 8th AAAI Conference on Human Computation and Crowdsourcing (HCOMP 2020). [PDF]
[CSCW 2020] CrowdCO-OP: Sharing Risks and Rewards in Crowdsourcing. Shaoyang Fan, Ujwal Gadiraju, Alessandro Checco, Gianluca Demartini. In Proceedings of the ACM on Human-Computer Interaction (CSCW 2020). [PDF]
[NFW 2020] Remote Work Aided By Conversational Agents. Sihang Qiu, Ujwal Gadiraju, Alessandro Bozzon. In Proceedings of the Microsoft Symposium on the New Future of Work (NFW 2020). [PDF]

[WISE 2020] TaskGenie: Crowd-powered Generation of Struggling Search Tasks. Luyan Xu, Xuan Zhou, Ujwal Gadiraju. In Proceedings of the 21st International Conference on Web Information Systems Engineering (WISE 2020). [PDF]
[ICTIR 2020] Towards Memorable Information Retrieval. Sihang Qiu, Ujwal Gadiraju, Alessandro Bozzon. In Proceedings of the ACM SIGIR International Conference on the Theory of Information Retrieval (ICTIR 2020). [PDF]

[HT 2020] How Does Team Composition Affect Knowledge Gain of Users in Collaborative Web Search?. Luyan Xu, Xuan Zhou, Ujwal Gadiraju. In Proceedings of the ACM Conference on Hypertext and Social Media (HT 2020). [PDF]

[CSCW 2020] Estimating Conversational Styles in Conversational Microtask Crowdsourcing. Sihang Qiu, Ujwal Gadiraju, Alessandro Bozzon. In Proceedings of the ACM on Human-Computer Interaction (CSCW 2020). [PDF] [Demo]
[ICWE 2020] Just the Right Mood for HIT! Analyzing the Role of Worker Moods in Conversational Microtask Crowdsourcing. Sihang Qiu, Ujwal Gadiraju, Alessandro Bozzon. Proceedings of the International Conference on Web Engineering (ICWE 2020). [PDF]

[Sensors 2020] Crowd of Oz: A Crowd-Powered Social Robotics System for Stress Management. Tahir Abbas, Vassilis-Javed Khan, Ujwal Gadiraju, Emilia I. Barakova, Panos Markopoulos. In Proceedings of the MDPI Journal (Sensors 2020). [PDF]
[CHI 2020] Improving Worker Engagement Through Conversational Microtask Crowdsourcing. Sihang Qiu, Ujwal Gadiraju, Alessandro Bozzon. In Proceedings of the ACM International Conference on Human Factors in Computing Systems (CHI 2020). [PDF]

[HRI 2020] How do People Perceive Privacy and Interaction Quality while Chatting with a Crowd-operated Robot?. Tahir Abbas, Giovanni Corpaccioli, Vassilis-Javed Khan, Ujwal Gadiraju, Emilia Barakova, Panos Markopoulos. In Companion of the 2020 ACM/IEEE International Conference on Human-Robot Interaction (HRI 2020). [PDF]

[HRI 2020] Crowd of Oz: A Crowd-powered Teleoperation System for Enhanced Human-Robot Conversations. Tahir Abbas, Vassilis-Javed Khan, Ujwal Gadiraju, Emilia Barakova, Panos Markopoulos. In Companion of the 2020 ACM/IEEE International Conference on Human-Robot Interaction (HRI 2020). [PDF]

[WSDM 2020] Crowd Worker Strategies in Relevance Judgment Tasks. Lei Han, Eddy Maddalena, Alessandro Checco, Cristina Sarasua, Ujwal Gadiraju, Kevin Roitero, Gianluca Demartini. In Proceedings of the ACM International Conference on Web Search and Data Mining (WSDM 2020). [PDF]
[WIDM 2020] Bias in Data-driven AI Systems - An Introductory Survey. Eirini Ntoutsi, Pavlos Fafalios, Ujwal Gadiraju, Vasileios Iosifidis, Wolfgang Nejdl, Maria-Esther Vidal, Salvatore Ruggieri, Franco Turini, Symeon Papadopoulos, Emmanouil Krasanakis, Ioannis Kompatsiaris, Katharina Kinder-Kurlanda, Claudia Wagner, Fariba Karimi, Miriam Fernández, Harith Alani, Bettina Berendt, Tina Kruegel, Christian Heinze, Klaus Broelemann, Gjergji Kasneci, Thanassis Tiropanis, Steffen Staab. In WIREs Data Mining and Knowledge Discovery (WIDM 2020). [PDF]

2019

[TKDE 2019] The Impact of Task Abandonment in Crowdsourcing. Lei Han, Kevin Roitero, Ujwal Gadiraju, Cristina Sarasua, Alessandro Checco, Eddy Maddalena, Gianluca Demartini. IEEE Transactions on Knowledge and Data Engineering (TKDE 2019). [PDF]
[CSCW 2019] Dissonance Between Human and Machine Understanding. Zijian Zhang, Jaspreet Singh, Ujwal Gadiraju, Avishek Anand. In Proceedings of the ACM on Human-Computer Interaction (CSCW 2019). [PDF] [Slides]

[HT 2019] Understanding Worker Moods and Reactions to Rejection in Crowdsourcing. Ujwal Gadiraju, Gianluca Demartini. In Proceedings of the ACM Conference on Hypertext and Social Media (HT 2019). [PDF] [Slides]

[HT 2019] Understanding User Search Behavior Across Varying Cognitive Levels. Rishita Kalyani, Ujwal Gadiraju. In Proceedings of the ACM Conference on Hypertext and Social Media (HT 2019). [PDF]
[SIGIR 2019] Revealing the Role of User Moods in Struggling Search Tasks. Luyan Xu, Xuan Zhou, Ujwal Gadiraju. In Proceedings of the 42nd International ACM SIGIR Conference on Research and Development in Information Retrieval (SIGIR 2019). [PDF]
[WebScience 2019] In What Mood Are You Today? An Analysis of Crowd Workers’ Mood, Performance and Engagement. Mengdie Zhuang, Ujwal Gadiraju. In Proceedings of the ACM Conference on Web Science (WebSci 2019). [PDF]
[UMAP 2019] Chatterbox: Conversational Interfaces for Microtask Crowdsourcing. Panagiotis Mavridis, Owen Huang, Sihang Qiu, Ujwal Gadiraju, Alessandro Bozzon. In Proceedings of the ACM Conference on User Modeling, Adaptation and Personalization (UMAP 2019). [PDF]
[CHI 2019] Understanding and Mitigating Worker Biases in the Crowdsourced Collection of Subjective Judgments. Christoph Hube, Besnik Fetahu, Ujwal Gadiraju. In Proceedings of the ACM International Conference on Human Factors in Computing Systems (CHI 2019). [PDF] [Blog]
[WSDM 2019] All Those Wasted Hours: On Task Abandonment in Crowdsourcing. Lei Han, Kevin Roitero, Ujwal Gadiraju, Cristina Sarasua, Alessandro Checco, Eddy Maddalena, and Gianluca Demartini. In Proceedings of the ACM International Conference on Web Search and Data Mining (WSDM 2019). [PDF]
[SWJ 2019] KnowMore - Knowledge Base Augmentation With Structured Web Markup. Ran Yu, Ujwal Gadiraju, Besnik Fetahu, Oliver Lehmberg, and Stefan Dietze. In Proceedings of the Semantic Web Journal (SWJ 2019). [PDF]

2018

[HCOMP 2018] LimitBias! Measuring Worker Biases in the Crowdsourced Collection of Subjective Judgments. Christoph Hube, Besnik Fetahu, and Ujwal Gadiraju. In Proceedings of the CrowdBias’18 Workshop at AAAI Conference on HUman Computation and Crowdsourcing (HCOMP 2018). [PDF]
[HCOMP 2018] Effects of Algorithmic Decision-Making and Interpretability on Human Behavior: Experiments using Crowdsourcing. Avishek Anand, Kilian Bizer, Alexander Erlei, Ujwal Gadiraju, Christian Heinze, Lukas Meub, Wolfgang Nejdl and Bjoern Steinroetter. In Proceedings of the CrowdBias’18 Workshop at AAAI Conference on HUman Computation and Crowdsourcing (HCOMP 2018). [PDF]
[SIGIR 2018] Predicting User Knowledge Gain in Informational Search Sessions. Luyan Xu, Xuan Zhou, Ujwal Gadiraju. In Proceedings of the 41st International ACM SIGIR Conference on Research and Development in Information Retrieval (SIGIR 2018). [PDF]
[JCSCW 2018] Crowd Anatomy Beyond the Good and Bad: Behavioral Traces for Crowd Worker Modeling and Pre-selection. Ujwal Gadiraju, Gianluca Demartini, Ricardo Kawase, and Stefan Dietze. In the Computer Supported Cooperative Work (CSCW) Journal - The Journal of Collaborative Computing and Work Practices (JCSCW 2018). [PDF]
[HT 2018] SimilarHITs: Revealing the Role of Task Similarity in Microtask Crowdsourcing. Alan Aipe and Ujwal Gadiraju. In Proceedings of the ACM Conference on Hypertext and Social Media (HT 2018). [PDF]
[CHIIR 2018] Analyzing Knowledge Gain of Users in Informational Search Sessions on the Web. Ujwal Gadiraju, Ran Yu, Stefan Dietze and Peter Holtz. In Proceedings of the ACM SIGIR Conference on Human Information Interaction and Retrieval (CHIIR 2018). [PDF]

2017

[UBICOMP 2017] Modus Operandi of Crowd Workers : The Invisible Role of Microtask Work Environments. Ujwal Gadiraju, Alessandro Checco, Neha Gupta, and Gianluca Demartini. In Proceedings of the ACM on Interactive, Mobile, Wearable and Ubiquitous Technologies (IMWUT 2017). [PDF]
[TOCHI 2017] Using Worker Self-Assessments for Competence-based Pre-selection in Crowdsourcing Microtasks. Ujwal Gadiraju, Besnik Fetahu, Ricardo Kawase, Patrick Siehndel and Stefan Dietze. In ACM Transactions on Computer-Human Interaction (TOCHI 2017). [PDF]
[HT 2017] Clarity is a Worthwhile Quality - On the Role of Task Clarity in Microtask Crowdsourcing. Ujwal Gadiraju, Jie Yang and Alessandro Bozzon. In Proceedings of the ACM Conference on Hypertext and Social Media (HT 2017). [PDF] 🏆 Best Paper Award 🏆
[ICWE 2017] Improving Reliability of Crowdsourced Results by Detecting Crowd Workers with Multiple Identities. Ujwal Gadiraju and Ricardo Kawase. In Proceedings of the International Conference on Web Engineering (ICWE 2017). [PDF]
[LAK 2017] Improving Learning Through Achievement Priming in Information Finding Microtasks. Ujwal Gadiraju and Stefan Dietze. In Proceedings of the ACM International Conference on Learning Analytics and Knowledge. [PDF]
[ICDE 2017] FuseM: Query-Centric Data Fusion on Structured Web Markup. Ran Yu, Ujwal Gadiraju, Besnik Fetahu and Stefan Dietze. In Proceedings of the IEEE International Conference on Data Engineering (ICDE 2017). [PDF]
[ECIR 2017] JustEvents: A Crowdsourced Corpus for Event Validation with Strict Temporal Constraints. Andrea Ceroni, Ujwal Gadiraju and Marco Fisichella. In Proceedings of the European Conference on Information Retrieval (ECIR 2017). [PDF] [DATA]

2016

[WebSci 2016] Estimating Domain Specificity for Effective Crowdsourcing of Link Prediction and Schema Mapping. Ujwal Gadiraju, Patrick Siehndel and Stefan Dietze. In Proceedings of the ACM Conference on Web Science (WebSci 2016). [PDF] 🏆 Best Poster Award 🏆
[WebSci 2016] Crystal Clear or Very Vague? Effects of Task Clarity in the Microtask Crowdsourcing Ecosystem. Ujwal Gadiraju, Besnik Fetahu and Christoph Hube. In Proceedings of the Trust In Crowd Work Workshop at ACM Conference on Web Science (WebSci 2016). [PDF]
[Crowd Dynamics 2016] Dealing With Sub-optimal Crowd Work : Implications of Current Quality Control Practices. Ujwal Gadiraju and Neha Gupta. In Proceedings of Crowd Dynamics Workshop at the ACM Conference on Human Factors in Computing Systems (CHI 2016). [PDF]
[Productivity Decomposed 2016] Cognitive Factors that Influence Workers’ Task Performance in Crowdsourcing Microtasks. Darren J. Edwards and Ujwal Gadiraju. In Proceedings of the Productivity Decomposed Workshop at the ACM Conference on Human Factors in Computing Systems (CHI 2016). [PDF]
[SAVE-SD 2016] Analysing Structured Scholarly Data embedded in Web Pages. Pracheta Sahoo, Ujwal Gadiraju, Ran Yu, Sriparna Saha and Stefan Dietze. In Proceedings of the Semantics, Analytics, Visualisation: Enhancing Scholarly Data (SAVE-SD) Workshop at the International World Wide Web Conference (WWW 2016). [PDF]
[EDBT/ICDT 2016] Unlock the Stock: User Topic Modeling for Stock Market Analysis. Patrick Siehndel and Ujwal Gadiraju. In the Workshop Proceedings of the EDBT/ICDT 2016 Joint Conference (EDBT/ICDT 2016). [PDF]

2015

[CHI 2015] Understanding Malicious Behavior in Crowdsourcing Platforms: The Case of Online Surveys. Ujwal Gadiraju, Ricardo Kawase, Stefan Dietze, and Gianluca Demartini. In Proceedings of the ACM International Conference on Human Factors in Computing Systems (CHI 2015). [PDF] [Slides]
[IEEE IS 2015] Human Beyond the Machine: Challenges and Opportunities of Microtask Crowdsourcing. Ujwal Gadiraju, Gianluca Demartini, Ricardo Kawase, and Stefan Dietze. In Proceedings of the IEEE Intelligent Systems, Volume 30 Issue 4. [PDF]
[WebSci 2015] Ranking Buildings and Mining the Web for Popular Architectural Patterns. Ujwal Gadiraju, Stefan Dietze, and Ernesto Diaz-Aviles. In Proceedings of the ACM Conference on Web Science (WebSci 2015). [PDF] [Slides]
[ISWC 2015] Improving Entity Retrieval on Structured Data. Besnik Fetahu, Ujwal Gadiraju, Stefan Dietze. In Proceedings of the International Semantic Web Conference (ISWC 2015). [PDF]
[ECTEL 2015] Training Workers for Improving Performance in Crowdsourcing Microtasks. Ujwal Gadiraju, Besnik Fetahu, and Ricardo Kawase. In Proceedings of the ACM Conference on Web Science (WebSci 2015). [PDF] [Slides]
[HT 2015] Breaking Bad - Understanding Behavior of Crowd Workers in Categorization Microtasks. Ujwal Gadiraju, Ricardo Kawase, Patrick Siehndel, and Besnik Fetahu. In Proceedings of the ACM Conference on Hypertext and Social Media (HT 2015). [PDF] [Slides]
[WWW 2015] Make Hay While the Crowd Shines: Towards Efficient Crowdsourcing on the Web. Ujwal Gadiraju, Ricardo Kawase, Patrick Siehndel, and Besnik Fetahu. In Proceedings of the International World Wide Web Conference (WWW 2015). [PDF] [Slides]
[CIKM 2015] Improving Event Detection by Automatically Assessing Validity of Event Occurrence in Text. Tuan Tran, Claudia Niederée, Nattiya Kanhabua, Ujwal Gadiraju, and Avishek Anand. In Proceedings of the ACM International Conference on Information and Knowledge Management (CIKM 2015). [PDF] [Slides]
[WISE 2015] Adaptive Focused Crawling of Linked Data. Ran Yu, Ujwal Gadiraju, Besnik Fetahu and Stefan Dietze. In Proceedings of Web Information Systems Engineering (WISE 2015). [PDF] [Slides]

2014

[ISWC 2014] Extracting Architectural Patterns from Web Data. Ujwal Gadiraju, Ricardo Kawase, and Stefan Dietze. In Proceedings of the International Semantic Web Conference (ISWC 2014). [PDF] 🏆 Best Poster Award 🏆
[ISWC 2014] Crawl Me Maybe: Iterative Linked Dataset Preservation. Besnik Fetahu, Ujwal Gadiraju, Stefan Dietze. In Proceedings of the International Semantic Web Conference (ISWC 2014). [PDF]
[ISWC 2014] WikipEvent: Temporal Event Data for the Semantic Web. Ujwal Gadiraju, Kaweh Djafari Naini, Andrea Ceroni, Mihai Georgescu, Dang Duc Pham, and Marco Fisichella. In Proceedings of the International Semantic Web Conference (ISWC 2014). [PDF]
[HT 2014] A Taxonomy of Microtasks on the Web. Ujwal Gadiraju, Ricardo Kawase, and Stefan Dietze. In Proceedings of the ACM Conference on Hypertext and Social Media (HT 2014). [PDF]
[OpenSym 2014] Information Evolution in Wikipedia. Andrea Ceroni, Mihai Georgescu, Ujwal Gadiraju, Kaweh Djafari Naini, and Marco Fisichella. In Proceedings of the International Symposium on Open Collaboration (OpenSym 2014). [PDF]
[ECTEL 2014] Technology Enhancing Learning: Past, Present and Future. Ricardo Kawase, Patrick Siehndel, and Ujwal Gadiraju. In Proceedings of the European Conference on Technology Enhancing Learning (ECTEL 2014). [PDF]
[WIMS 2014] When in Doubt Ask the Crowd: Employing Crowdsourcing for Active Learning. Mihai Georgescu, Dang Duc Pham, Claudiu S Firan, Ujwal Gadiraju, and Wolfgang Nejdl. In Proceedings of the International Conference on Web Intelligence, Mining and Semantics (WIMS 2014). [PDF]

2013

[SDA 2013] Towards Preservation of Semantically Enriched Architectural Knowledge. Stefan Dietze, Jakob Beetz, Ujwal Gadiraju, Georgios Katsimpras, Raoul Wessel, and René Berndt. In Proceedings of the International Workshop on Semantic Digital Archives (SDA 2013). [PDF]
[WWW 2013] Groundhog Day: Near-duplicate Detection on Twitter. Ke Tao, Fabian Abel, Claudia Hauff, Geert-Jan Houben, and Ujwal Gadiraju. In Proceedings of the International World Wide Web Conference (WWW 2013). [PDF]