Diss. Stockholm : Handelshögsk., 2001.

The purpose of this paper is to examine properties of the mean integral. The mean integral is compared with the regular integral. If [a;b] is an interval, f is quasicontinuous on [a;b] and g has bounded variation on [a;b], then the man integral of f with respect to g exists on [a;b]. The following theorem is proved. If [a*;b*] and [a;b] each is an interval and h is a function from [a*;b*] into R, then the following two statements are equivalent: 1) If f is a function from [a;b] into [a*;b*], gi is a function from [a;b] into R with bounded variation and (m)∫^b_afdg exists then (m)∫^b_ah(f)dg exists. 2) h is continuous.

Zugl.: Darmstadt, Techn. Univ., Diss., 2006

Techn. Univ., Diss--Darmstadt, 2006.

Query answering over big data is cost-prohibitive. A linear scan of a dataset D may take days with a solid state device if D is of PB size and years if D is of EB size. In other words, polynomial-time (PTIME) algorithms for query evaluation are already not feasible on big data. To tackle this, we propose querying big data with bounded data access, such that the cost of query evaluation is independent of the scale of D. First of all, we propose a class of boundedly evaluable queries. A query Q is boundedly evaluable under a set A of access constraints if for any dataset D that satisfies constraints in A, there exists a subset DQ ⊆ D such that (a) Q(DQ) = Q(D), and (b) the time for identifying DQ from D, and hence the size |DQ| of DQ, are independent of |D|. That is, we can compute Q(D) by accessing a bounded amount of data no matter how big D grows.We study the problem of deciding whether a query is boundedly evaluable under A. It is known that the problem is undecidable for FO without access constraints. We show that, in the presence of access constraints, it is decidable in 2EXPSPACE for positive fragments of FO queries, but is already EXPSPACE-hard even for CQ. To handle the undecidability and high complexity of the analysis, we develop effective syntax for boundedly evaluable queries under A, referred to as queries covered by A, such that, (a) any boundedly evaluable query under A is equivalent to a query covered by A, (b) each covered query is boundedly evaluable, and (c) it is efficient to decide whether Q is covered by A. On top of DBMS, we develop practical algorithms for checking whether queries are covered by A, and generating bounded plans if so. For queries that are not boundedly evaluable, we extend bounded evaluability to resource-bounded approximation and bounded query rewriting using views. (1) Resource-bounded approximation is parameterized with a resource ratio a ∈ (0,1], such that for any query Q and dataset D, it computes approximate answers with an accuracy bound h by accessing at most a|D| tuples. It is based on extended access constraints and a new accuracy measure. (2) Bounded query rewriting tackles the problem by incorporating bounded evaluability with views, such that the queries can be exactly answered by accessing cached views and a bounded amount of data in D. We study the problem of deciding whether a query has a bounded rewriting, establish its complexity bounds, and develop effective syntax for FO queries with a bounded rewriting. Finally, we extend bounded evaluability to graph pattern queries, by extending access constraints to graph data. We characterize bounded evaluability for subgraph and simulation patterns and develop practical algorithms for associated problems.

In this thesis we study some of the problems which occur when type inference is used in a type system with subtyping. An underlying poset of atomic types is used as a basis for our subtyping systems. We argue that the class of Helly posets is of significant interest, as it includes lattices and trees, and is closed under type formation not only with structural constructors such as function space and list, but also records, tagged variants, Abadi-Cardelli object constructors, top and bottom. We develop a general theory relating consistency, solvability, and solution of sets of constraints between regular types built over Helly posets with these constructors, and introduce semantic notions of simplification and entailment for sets of constraints over Helly posets of base types. We extend Helly posets with inequalities of the form a <= tau, where tau is not necessarily atomic, and show how this enables us to deal with bounded quantification. Using bounded quantification we define a subtyping system which combines structural subtype polymorphism and predicative parametric polymorphism, and use this to extend with subtyping the type system of Laufer and Odersky for ML with type annotations. We define a complete algorithm which infers minimal types for our extension, using factorisations, solutions of subtyping problems analogous to principal unifiers for unification problems. We give some examples of typings computed by a prototype implementation.

This paper is primarily concerned with developing the theory of real-valued functions of bounded variation and those ideas which are closely related to this main topic. In addition to this, some emphasis has been placed on the relationship of the theory of functions of bounded variation to specific areas of analysis. In particular, integration theory has been chosen as the vehicle to demonstrate this connection.

It is not easy to predict what will happen tomorrow. It is perhaps even more difficult knowing what will occur next year or even two years from today. To put it short we are uncertain about the future. Swedish firms attempting to capture new export markets are also facing uncertainty. If a firm succeeds with predicting customer’s preferences they might be able to create a position for the firm´s products before any competition. It is however almost amusing to study successful marketing cases for export markets in a rear window. It is striking how firms have found winning positions which captured market after market with such apparent ease.  In this thesis the author attempts to present theoretical frameworks including internationalization theory and traditional marketing theory which can support exporting firms attempts to find new positions on export markets.  Previously in traditional marketing theory the solution has been to put trust in the marketing concept. Success in the marketplace was then a result of a careful segmentation process ending up in a positioning-decision supported by the marketing mix. The Nordic school of marketing among others introduced a new track in marketing with the relationship marketing concept focusing on the development of existing customer relationships. Internationalization theory (the process theory of internationalization) suggested that that firms increase commitment on export markets after a gradual learning process. Effectuation on the other hand has offered new perspectives. With its roots in the paradigm of bounded rationality a differing stance is offered for predicting the unpredictable. By following a model of bounded rationality the presented firms manage to craft positions for new and as a matter of fact as presented in the empirical part, also for existing markets. The paper highlights the importance of positioning for Swedish firms success on export markets.  It is a case study of how Swedish firms craft positions on new markets by taking action instead of making formal positioning decisions.  A model of bounded rationality is tested during interviews with five Swedish top-exporting firms. The paper finally presents a revised developed model for how successful firms act on export markets in order to craft positions. The model includes traditional marketing theory based upon a paradigm of bounded rationality. The paper contains however some question marks for the application of the marketing concept and traditional marketing theory. Rather a stance towards bounded rationality is emphasized.The final point of the thesis is the urge for emergence of alternatives in marketing to the marketing concept founded upon bounded rationality. These new models need to capture the actual actions taken by successful exporting firms in a more proficient and graspable way than existing traditional marketing models.

<p>It is not easy to predict what will happen tomorrow. It is perhaps even more difficult knowing what will occur next year or even two years from today. To put it short we are uncertain about the future. Swedish firms attempting to capture new export markets are also facing uncertainty. If a firm succeeds with predicting customer’s preferences they might be able to create a position for the firm´s products before any competition. It is however almost amusing to study successful marketing cases for export markets in a rear window. It is striking how firms have found winning positions which captured market after market with such apparent ease.  In this thesis the author attempts to present theoretical frameworks including internationalization theory and traditional marketing theory which can support exporting firms attempts to find new positions on export markets.  Previously in traditional marketing theory the solution has been to put trust in the marketing concept. Success in the marketplace was then a result of a careful segmentation process ending up in a positioning-decision supported by the marketing mix. The Nordic school of marketing among others introduced a new track in marketing with the relationship marketing concept focusing on the development of existing customer relationships. Internationalization theory (the process theory of internationalization) suggested that that firms increase commitment on export markets after a gradual learning process. Effectuation on the other hand has offered new perspectives. With its roots in the paradigm of bounded rationality a differing stance is offered for predicting the unpredictable. By following a model of bounded rationality the presented firms manage to craft positions for new and as a matter of fact as presented in the empirical part, also for existing markets.</p><p>The paper highlights the importance of positioning for Swedish firms success on export markets.  It is a case study of how Swedish firms craft positions on new markets by taking action instead of making formal positioning decisions.  A model of bounded rationality is tested during interviews with five Swedish top-exporting firms. The paper finally presents a revised developed model for how successful firms act on export markets in order to craft positions. The model includes traditional marketing theory based upon a paradigm of bounded rationality. The paper contains however some question marks for the application of the marketing concept and traditional marketing theory. Rather a stance towards bounded rationality is emphasized.The final point of the thesis is the urge for emergence of alternatives in marketing to the marketing concept founded upon bounded rationality. These new models need to capture the actual actions taken by successful exporting firms in a more proficient and graspable way than existing traditional marketing models.</p>

The objective of this research is to develop the framework of empirical-evidence equilibria (EEEs) in stochastic games. This framework was developed while attempting to design decentralized controllers using learning in stochastic games. The overarching goal is to enable a set of agents to control a dynamical system in a decentralized fashion. To do so, the agents play a stochastic game crafted such that its equilibria are decentralized controllers for the dynamical system. Unfortunately, there exists no algorithm to compute equilibria in stochastic games. One explanation for this lack of results is the full-rationality requirement of game theory. In the case of stochastic games, full rationality imposes that two requirements be met at equilibrium. First, each agent has a perfect model of the game and of its opponents strategies. Second, each agent plays an optimal strategy for the POMDP induced by its opponents strategies. Both requirements are unrealistic. An agent cannot know the strategies of its opponents; it can only observe the combined effect of its own strategy interacting with its opponents. Furthermore, POMDPs are intractable; an agent cannot compute an optimal strategy in a reasonable time. In addition to these two requirements, engineered agents cannot carry perfect analytical reasoning and have limited memory; they naturally exhibit bounded rationality. In this research, bounded rationality is not seen as a limitation and is instead used to relax the two requirements. In the EEE framework, agents formulate low-order empirical models of observed quantities called mockups. Mockups have unmodeled states and dynamic effects, but they are statistically consistent; the empirical evidence observed by an agent does not contradict its mockup. Each agent uses its mockup to derive an optimal strategy. 1Since agents are interconnected through the system, these mockups are sensitive to the specific strategies employed by other agents. In an EEE, the two requirements are weakened. First, each agent has a consistent mockup of the game and the strategies of its opponents. Second, each agent plays an optimal strategy for the MDP induced by its mockup. The main contribution of this dissertation is the use of modeling to study stochastic games. This approach, while common in engineering, had not been applied to stochastic games.