constructors. Friendly corecursive functions can be registered as such, thereby increasing the corecursor’s expressiveness. The metatheory is formalized in the Isabelle proof assistant and forms the core of a prototype tool. The corecursor is derived from first principles, without requiring new axioms

constructors. Corecursive functions that are well behaved can be registered as such, thereby increasing the corecursor’s expressiveness. To the extensible corecursor cor-responds an equally flexible coinduction principle. The metatheory is formalized in the Isabelle proof assistant and forms the core of a

broadly British cultural studies' perspective, and this needs to be kept in mind. As Graeme Turner (a key figure in Australian cultural studies) has observed, alternative traditions of cultural studies tend to have to announce themselves as such, something which suggests a certain Anglo

in corecursive definitions. In this paper, we propose an extension of the Calculus of Constructions—the theory underlying the Coq proof assistant—with a type-based criterion for ensuring productivity of stream definitions. We prove strong normalization and logical consistency. Furthermore, we define an algorithm

Abstract: Online learning initia-tives over the past decade have become increasingly comprehen-sive in their selection of courses and sophisticated in their presen-tation, culminating in the recent announcement of a number of consortium and startup activities that promise to make a university

cover in this paper have been influenced by an extensive collaboration with Thomas Sargent. I greatly appreciate conversations with Xiaohong Chen, John Heaton, Ravi Jagannathan, Monika Piazzesi and Martin Schneider. I owe a special acknowledgement to Thomas Sargent and Grace Tsiang who provided

in the ambition to deliver a sophisticated system to end-users without requiring self-assembly of individual parts. Isabelle today is probably the most advanced proof assistant concerning its overall architecture and extra-logical infrastructure. The “Isar ” aspect of Isabelle refers first to the structured

Abstract Basic ideas of rough set theory were proposed by Zdzis law Pawlak [85, 86] in the early 1980’s. In the ensuing years, we have witnessed a systematic, world–wide growth of interest in rough sets and their applications. The main goal of rough set analysis is induction of approximations

and em-powerment. Whereas these systems may vary in the domain of application and the precise manner of intelligent assis-tance, there exist several fundamental similarities from a systemic and information-theoretic viewpoint with regard to the ontological and computational foundations that underlie

comparisons. Then, noting that Lycinus seldom has been generous in his assessments of others, Polystratus encourages Lycinus to be more restrained in his compliments in this case. As well, Polystratus says, even the great sculptor Phidias [also Pheidias] extensively reworked a statue of Zeus after