  Domain experts increasingly use automated data science tools to incorporate
machine learning (ML) models in their work but struggle to "debug" these models
when they are incorrect. For these experts, semantic interactions can provide
an accessible avenue to guide and refine ML models without having to
programmatically dive into its technical details. In this research, we conduct
an elicitation study using data and visual design probes to examine if and how
experts with a spectrum of ML expertise use semantic interactions to update a
simple classification model. We use our design probes to facilitate an
interactive dialogue with 20 participants and codify their interactions as a
set of target-interaction pairs. Interestingly, our findings revealed that many
targets of semantic interactions do not directly map to ML model parameters,
but instead aim to augment the data a model uses for training. We also identify
reasons that participants would hesitate to interact with ML models, including
burdens of cognitive load and concerns of injecting bias. Unexpectedly
participants also saw the value of using semantic interactions to work
collaboratively with members of their team. Participants with less ML expertise
found this to be a useful mechanism for communicating their concerns to ML
experts. This was an especially important observation, as our study also shows
the different needs that correspond to diverse ML expertise. Collectively, we
demonstrate that design probes are effective tools for proactively gathering
the affordances that should be offered in an interactive machine learning
system.
