Topic Modeling has been widely used by data scientists to analyze the increasing amount of text documents. Documents can be assigned to a distribution of topics with techniques like LDA or NMF, that are related to unsupervised soft clustering but consider text semantics. More recently, Interactive Topic Modeling (ITM) has been introduced to incorporate human expertise in the modeling process. This enables real-time hyperparameter optimization and topic manipulation on document and keyword level. However, current ITM applications are mostly accessible to experienced data scientists, who lack domain knowledge. Domain experts, on the other hand, usually lack the data science expertise to build and use ITM applications.
This thesis presents an Interactive Topic Modeling application accessible to non-technical data analysts in the broadcasting domain. The application allows domain experts, like journalists, to explore themes in various produced media content in a dynamic, intuitive and efficient manner. An interactive interface, with an embedded NMF topic model, enables users to filter on various data sources, configure and refine the topic model, interpret and evaluate the output by visualizations, and analyze the data in wider context. This application was designed in collaboration with domain experts in focus group sessions, according to human-centered design principles.
An evaluation study with ten participants shows that journalists and data analysts without any natural language processing knowledge agree that the application is not only usable, but also very user-friendly, effective and efficient. A SUS score of 81 was received, and user experience and user perceptions of control questionnaires both received an average of 4.1 on a five-point Likert scale. The ITM application thus enables this specific user group to extract meaningful topics from their produced media content, and use these results in broader perspective to perform exploratory data analysis.
The success of the final application design presented in this thesis shows that the knowledge gap between data scientists and domain experts in the broadcasting field has been filled. In bigger perspective; machine learning applications can be made more accessible by translating hidden low-level details of complex models into high-level model interactions, presented in a user interface
