  The challenge of raising a creative question exists in recombining different
categories of knowledge. However, the impact of recombination remains
controversial. Drawing on the theories of knowledge recombination and category
spanning, we propose that both the distance of knowledge spanning and the
hierarchy of knowledge shape the appeal of questions. Using word embedding
models and the data collected from a large online knowledge market (N =
463,545), we find that the impact of knowledge spanning on the appeal of
questions is parabolic: the appeal of questions increases up to a threshold,
after which point the positive effect reverses. However, the nonlinear
influence of knowledge spanning is contingent upon the hierarchy of knowledge.
The theoretical and practical implications of these findings for future
research on knowledge recombination are discussed. We fill the research gap by
conceptualizing question asking as knowledge spanning and highlighting the
theoretical underpinnings of the knowledge hierarchy.
