Jiye Baek

Social media have great potential to support diverse information sharing, but there is widespread concern that platforms like Twitter do not result in communication between those who hold contradictory viewpoints. Because users can choose whom to follow, prior research suggests that social media users exist in echo chambers or become polarized. We seek evidence of this in a complete cross section of hyperlinks posted on Twitter, using previously validated measures of the political slant of news

Promoting contribution of content is a key challenge for platforms that support the collective creation or transfer of knowledge. We use a field experiment on a massive open online course to study the role of forum size (number of people in a forum) in the contribution of content per person. We find that larger forums elicit more contributions per person. The number of questions and other help-seeking threads posted per person was unchanged by forum size, but replies and other more conversationa

MOOCs offer valuable learning experiences to students from all around the world. In addition to providing filmed lectures, readings, and problem sets, many MOOCs allow students to ask and answer questions about course materials with each other through interactive user forums. However, in current MOOCs, only 3 to 5 percent of those students interact in the user forum (Breslow 2013, Rosé et al. 2014) and more than 90 percent of students stop attending the course altogether (Jordan 2014). According

Social media have great potential to support diverse information sharing, but there is widespread concern that platforms like Twitter do not result in communication between those who hold contradictory viewpoints. Because users can choose whom to follow, prior research suggests that social media users exist in "echo chambers" or become polarized. We seek evidence of this in a complete cross section of hyperlinks posted on Twitter, using previously validated measures of the political slant of new

Artificial Intelligence (AI) is revolutionizing education, particularly with advancements in generative AI conversational agents. Our study investigates the effectiveness of these generative AI agents in enhancing English-speaking skills compared to human agents. Through a randomized field experiment involving 363 participants, we found that unrestricted use of AI tools led to a 5.90% improvement in lexical diversity, as measured by the Type-Token Ratio (TTR), highlighting the benefits of self-p

Promoting contribution of content is a key challenge for platforms that support the collective creation or transfer of knowledge. We study the role of forum size (number of people in a forum) on contribution of content per person with a field experiment on a massive open online course (MOOC). We find that larger forums elicit more contribution per person. The number of questions and other help-seeking threads posted per person was unchanged by size, but replies and other more conversational post

To what extent do social media like Twitter support diversity of ideas and communication between those who hold contradictory viewpoints? Despite the evident potential for social media in this regard, two prominent theories predict that such diverse discourse may be very limited. We review the ideas of

Understanding online user engagement is a key challenge for social platforms that support the communal creation or transfer of knowledge and information. Engagement is not only a function of individual attributes but also the result of the social context that derives from platform choices. This dissertation presents several empirical examples of how social context shapes online engagement in social platforms such as social media or online communities. In the first chapter, I investigate how the