Uncertainty, incompleteness, and imprecision are common characteristics of the data and knowledge that we daily deal with in a wide range of domains and applications. Uncertainty management has been extensively studied in databases, artificial intelligence, and operations research for several decades. In the area of Internet technologies, uncertainty handling is an issue in e-commerce, social and sensor networks, scien-tific data production and exploration, objects tracking, data integration, location-based services, open linked data, and, recently, the Web of Things. For example, in the e-commerce domain alone, some recent studies [Soliman et al. 2010] have shown that approximately 65% of products (e.g., properties, cars, and so on) that one would find on typical e-commerce sites (e.g., apartments.com, carpages.ca) are associated with some uncertainty in their basic information (e.g., prices, locations, and descriptions).