Opening Up the Conversation: Topic Modeling for Automated Text Analysis in Travel Surveys. - Vishnu Baburajan; João de Abreu e Silva; Francisco Câmara Pereira (ITSC, 2018)

Open-Ended Versus Closed-Ended Responses: A Comparison Study Using Topic Modeling and Factor Analysis. - Vishnu Baburajan; João de Abreu e Silva; Francisco Câmara Pereira (IEEE Trans. Intell. Transp. Syst., 2021)

Open vs Closed-ended questions in attitudinal surveys - comparing, combining, and interpreting using natural language processing. - Vishnu Baburajan; João de Abreu e Silva; Francisco Câmara Pereira (CoRR, 2022)