  Recommender systems often struggle to strike a balance between matching
users' tastes and providing unexpected recommendations. When recommendations
are too narrow and fail to cover the full range of users' preferences, the
system is perceived as useless. Conversely, when the system suggests too many
items that users don't like, it is considered impersonal or ineffective. To
better understand user sentiment about the breadth of recommendations given by
a movie recommender, we conducted interviews and surveys and found out that
many users considered narrow recommendations to be useful, while a smaller
number explicitly wanted greater breadth. Additionally, we designed and ran an
online field experiment with a larger user group, evaluating two new interfaces
designed to provide users with greater access to broader recommendations. We
looked at user preferences and behavior for two groups of users: those with
higher initial movie diversity and those with lower diversity. Among our
findings, we discovered that different level of exploration control and users'
subjective preferences on interfaces are more predictive of their satisfaction
with the recommender.
