Every day, billions of mobile network events (commonly defined as Call Detailed Records, or CDRs) are generated by cellular phone operator companies. Latent in this data are inspiring insights about human actions and behaviors, the discovery of which is important because context-aware applications and services hold the key to user-driven, intelligent services, which can enhance our everyday lives. This potential has motivated preliminary research activities in a variety of domains such as social and economic development, urban planning, and health prevention. The major challenge in this area is that interpreting such a big stream of data requires a deep understanding of mobile network events' context through available background knowledge. Two of the most important factors in the events' context are location and time. This article addresses the issues in context awareness given heterogeneous and uncertain data of mobile network events missing reliable information on the context of this activity. The contribution of this research is a model from a combination of logical and statistical reasoning standpoints for enabling human activity inference in qualitative terms from open geographical data 1 arXiv:1504.05895v1 [cs.AI] 22 Apr 2015 that aimed at improving the quality of human behaviors recognition tasks from CDRs. We use open geographical data, Openstreetmap (OSM), as a proxy for predicting the content of human activity in the area. The user study performed in Trento city, Italy shows that predicted human activities (high level) from OSM match the survey data with around 93% overall accuracy, with fuzzy temporal constraints. The extensive analysis of the model validation for predicting a more specific-economical-type of human activity performed in Barcelona city, Spain, by employing credit card transaction data. This data gives us ground-truth information on what types of economic activity are occurring. The analysis identifies that appropriately normalized data on points of interest (POI) is a good proxy for predicting human economical activities, with 84% accuracy on average. So the model is proven to be efficient for predicting the context of human activity, when its total level could be efficiently observed from cell phone data records, missing contextual information however.