<p>Online decision making with switching costs has received considerable attention in many practical problems that face uncertainty in the inputs and key problem parameters. Because of the switching costs that penalize the change of decisions, making good online decisions under such uncertainty is known to be extremely challenging. This thesis aims at providing new online algorithms with strong performance guarantees to address this challenge.</p> <p><br></p> <p>In part 1 and part 2 of this thesis, motivated by Network Functions Virtualization and smart grid, we study competitive online convex optimization with switching costs. Specifically, in part 1, we focus on the setting with an uncertainty set (one type of prediction) and hard infeasibility constraints. We develop new online algorithms that can attain optimized competitive ratios, while ensuring feasibility at all times. Moreover, we design a robustification procedure that helps these algorithms obtain good average-case performance simultaneously. In part 2, we focus on the setting with look-ahead (another type of prediction). We provide the first algorithm that attains a competitive ratio that not only decreases to 1 as the look-ahead window size increases, but also remains upper-bounded for any ratio between the switching-cost coefficient and service-cost coefficient.</p> <p><br></p> <p>In part 3 of this thesis, motivated by edge computing with artificial intelligence, we study bandit learning with switching costs where, in addition to bandit feedback, full feedback can be requested at a cost. We show that, when only 1 arm can be chosen at a time, adding costly full-feedback is not helpful in fundamentally reducing the Θ(<em>T</em>2/3) regret over a time-horizon <em>T</em>. In contrast, when 2 (or more) arms can be chosen at a time, we provide a new online learning algorithm that achieves a significantly smaller regret equal to <em>O</em>(√<em>T</em>), without even using full feedback. To the best of our knowledge, this type of sharp transition from choosing 1 arm to choosing 2 (or more) arms has never been reported in the literature.</p>

Bakgrund: I Sverige finns det ett stort intresse för privat fondsparande. De svenska storbankerna erbjuder ett flertal fonder och utgör den huvudsakliga andelen av den svenska fondmarknaden. Fondförvaltares mål med en aktiv fond är att generera en högre avkastning jämfört med dess jämförelseindex, men tidigare forskning har visat att de svenska storbankernas aktiva fonder sällan presterar bättre än jämförelseindex. Syfte: Syftet med den här studien är att undersöka varför privatpersoner behåller fondinnehav i de svenska storbankernas aktiva fonder trots att tidigare studier visar att dessa fonder ofta har högre avgifter, men inte bättre avkastning jämfört med exempelvis indexfonder. Metod: Hypotesprövning har tillämpats med en kvantitativ ansats deriverad utifrån befintlig teori. Empiriska primärdata har samlats in med en fysisk enkätundersökning som 174 studenter vid Linköpings universitet har besvarat. I denna studie har ett icke-sannolikhetsurval med ett bekvämlighetsurval tillämpats. Bivariat och multivariat analys av studiens empiriska data har genomförts med logistisk regressionsanalys. Resultat: Nollhypotesen förkastas för den oberoende variabeln byteskostnader (p &lt;0,1). För de oberoende variablerna finansiell kunskap och familjär-bias förkastas nollhypotesen tills vidare (p &lt;0,1). Resultatet av beta-koefficientens riktning är negativ för byteskostnader avseende avgifter och andra finansiella kostnader, men positiv för relationskostnader, finansiell subjektiv och objektiv kunskap samt familjär-bias. Slutsats: De oberoende variabler som kan förklara varför privatpersoner i studiens urval behåller fondinnehav i de svenska storbankernas aktiva fonder är byteskostnader, finansiell kunskap och familjär-bias. Studiens resultat genererar ett kunskapsbidrag som kan öka kundrörligheten på fondmarknaden. / Background: In Sweden, there is a great interest in private fund savings. The major banks in Sweden offer several funds and constitute the majority of the Swedish fund market. Fund managers' goal with an active fund is to generate a higher return compared to its benchmark index, but previous research has shown that active funds rarely outperform the benchmark index. Purpose: The purpose of this study is to investigate why individuals retain fund holdings in the Swedish major banks’ active funds, although previous studies show that these funds often have higher fees, but not better returns than for example index funds. Methodology: Hypothesis testing has been applied with a quantitative approach derived from existing theory. Empirical primary data has been collected with a physical survey answered by 174 students at Linköping University. In this study, a non-probability sample with a convenience sample has been used. Bivariate and multivariate analysis of the study's empirical data was conducted with logistic regression analysis. Results: The null hypothesis is rejected for the independent variable switching costs (p &lt;0.1). For the independent variables financial knowledge and familiarity bias, the null hypothesis is rejected for the time being (p &lt;0.1). The result of the beta coefficient's direction is negative for switching costs regarding fees and other financial costs, but positive for relationship costs, financial subjective and objective knowledge, and familiarity bias. Conclusions: The independent variables, which might explain why private individuals in this study's sample retain fund holdings in the Swedish major banks' active funds, are switching costs, financial knowledge, and familiarity bias. The results of this study generate a knowledge contribution which might increase customer mobility in the fund market.

The thesis contains the theoretical basis for study of possibilities of pricing information goods. The source areas are microeconomics, marketing, competitive advantage and economics of information goods. The model of market is created with constraints defined on the ground of theoretical basis. The thesis analyzes requirements that define the system that supports the choice of pricing strategy. It includes detailed design of the prototype of such system. The prototype is designed with robustness because of the future improvements. The design describes the prototype's input parameters and their transformation into useful outputs that cover basic characteristics of information goods. The designed prototype is implemented. The thesis includes demonstration of the prototype and possible directions for improvements that lead to validity of proposed model of market.

The digital payment industry has become one of the fastest evolving markets in the world, but in the wake of its rapid advancement, an ever increasing gap between academic theory and the actual reality of this market widens - and especially so when it comes to entry theory. It is widely acknowledged that the world is moving towards an ever more homogeneous economy, but despite the fact that payment preferences differ greatly from country to country - research on this subject continues to revolve mainly around localized efforts. But as historical inequalities between poor and rich societies continue to dissipate - learning from nations at the forefront of technological advancement increases the likelihood that the developed strategy becomes applicable to an increased number of countries. By selecting a nation most conducive to technological growth, the purpose of this report is to map the present dynamics in its digital payment industry using both recent and traditional market entry theory. However, studies geared towards globalized strategy formulation cannot be assumed as having guaranteed access to internal company-data at all times. So in order to facilitate such studies, the level of dependency on primary data required for conducting such research needs to be understood first, which is why the work in this report is constrained strictly to data of secondary nature. This, not only to further map the characteristics of this market, but also to see how open the market is to public inspection. Ultimately, the academic contribution becomes that of providing a road-map towards adapting currently available market entry theory to suit the rapidly evolving conditions of the digital payment industry from a global perspective and, when failing to do so, the aim is to also explore avenues for further research towards this end goal.