  Context-aware reasoning systems allow drawing sophisticated inferences about
users' behaviour and physiological condition, by aggregating data from
seemingly unrelated sources. We conducted a general population online survey to
evaluate users' concern about the privacy of data gathered by these systems. We
found that people are more concerned about third parties accessing data
gathered by environmental sensors as compared to physiological sensors.
Participants also indicated greater concern about unfamiliar third parties
(e.g., private companies) as opposed to familiar third parties (e.g.,
relatives). We further found that these concerns are predicted and (to a lesser
degree) causally affected by people's beliefs about how much can be inferred
from these types of data, as well as by their background in computer science.
