1. A method for inferring activities associated with a user, the method comprising: receiving at least one location trace and corresponding contextual information; deriving a set of venues based on the location trace based on a venue database, wherein a respective hypothetical visit is associated with the contextual information corresponding to the location trace; deriving a set of activity types associated with a context based on the venues, the corresponding context indicated by the location trace, and a venue-to-activity mapping; receiving a user query context; identifying a number of activity types of which the associated contextual information is similar to the user query context; weighting a respective identified activity type based on its associated context's similarity to the user query context; normalizing weights associated with each identified activity type; and producing an activity-type probability distribution, thereby facilitating inferring activities associated with the user.