Non-linear anonymous pricing in combinatorial auctions

In combinatorial auctions the pricing problem is of main concern since it is the means by which the auctioneer signals the result of the auction to the participants. In order for the auction to be regarded as fair among the various participants the price signals should be such that a participant that has won a subset of items knows why his bid was a winning bid and that agents that have not acquired any item easily can detect why they lost. The problem in the combinatorial auction setting is that the winner determination problem is a hard integer programming problem and hence in general there does not exist a linear pricing scheme supporting the optimal allocation. This means that single item prices, that support the optimal allocation can in general not be found. In this article we present an alternative. From integer programming duality theory we know that there exist non-Iinear anonymous price functions that support the optimal allocation. In this paper we will provide a means to obtain a simple form of a non-Iinear anonymous price system that supports the optimal allocation. Our method relies on the fact that we separate the solution of the winner determination problem and the pricing problem. This separation yields a non-linear price function of a much simpler form compared to when the two problems are solved simultaneously. The pure pricing problem is formulated as a mixed-integer program. If solving this program is too demanding computationally a heuristic can be used which essentially requires us to solve a sequence of linear programming relaxations of a new mixed-integer programming formulation of the pricing problem. The procedure is computationally tested using instances of the combinatorial auctions test suite [17]

Non-linear anonymous pricing combinatorial auctions

In combinatorial auctions the pricing problem is of main concern since it is the means by which the auctioneer signals the result of the auction to the participants. In order for the auction to be regarded as fair among the various participants the price signals should be such that a participant that has won a subset of items knows why his bid was a winning bid and that agents that have not acquired any item easily can detect why they lost. The problem in the combinatorial auction setting is that the winner determination problem is a hard integer programming problem and hence a linear pricing scheme supporting the optimal allocation might not exist. From integer programming duality theory we know that there exist non-linear anonymous price functions that support the optimal allocation. In this paper we will provide a means to obtain a simple form of a non-linear anonymous price system that supports the optimal allocation. Our method relies on the fact that we separate the solution of the winner determination problem and the pricing problem. This separation yields a non-linear price function of a much simpler form compared to when the two problems are solved simultaneously. The pure pricing problem is formulated as a mixed-integer program. The procedure is computationally tested using difficult instances of the combinatorial auctions test suite [16]. The results indicate that the number of extreme prices forming the non-linear anonymous price system is small

Column aggregation-based pricing combinatorial auctions

Combinatorial auctions permitting bids on bundles of items have been developed to remedy the exposure problem associated with single-item auctions. Given winning bundle prices a set of item prices is called market clearing or equilibrium if all the winning bids are greater than or equal and if all the losing bids are less than or equal to the total price of the bundle items. However, the prices for individual items are not readily computed once the winner determination problem is solved. This is due to the duality gap of integer programming caused by the indivisibility of the items. In this paper we propose a family of linear programming models the optimal solution of which is integral "almost always", producing linear prices at the expense of having reduced cost zero for the aggregate winning bids only. We provide a computational proof of this conjecture by an in-depth experimental study of 18,000 instances from the combinatoriaI auction test suite (CATS; see [13]). Summarizing this analysis we have linear prices for all but five of the whole bunch of instances and, hence, there exists a linear price function that supports the optimal allocation of winning bundles

Entwicklung eines Arcade-inspirierten 2D Videospiels mit Unity

Diese Bachelorarbeit behandelt die praktische Umsetzung eines Arcade-inspirierten Videospiels mit der Game-Engine Unity. Der praktische Teil der Arbeit bildet den Hauptteil und wird in diesem Dokument durch eine Literaturarbeit theoretisch begleitet. Es werden grundlegende Prinzipien und Konzepte des Game-Designs behandelt und in das praktische Projekt überführt. Beginnend mit der Spieleidee, über die Konzeption bis hin zur Implementierung, findet sowohl eine praktische als auch eine theoretische Auseinandersetzung mit dem Thema Game-Design im Arcade-Game Genre, anhand eines praktischen Projektes statt. Begleitet von etablierter Literatur zu dem Thema, bezieht sich diese Arbeit insbesondere auf die Eigenheiten des Arcade-Game Genres und nimmt Bezug auf dessen Entstehungs- und Erfolgsgeschichte. Ziel ist es, fundiertes Wissen aus der Games Branche zu recherchieren, strukturieren und letztendlich praktisch anzuwenden. Mit dieser Vorgehensweise soll geklärt werden, was Arcade-Games im Kern ausmacht, woraus sie bestehen, was sie so beliebt macht und wie sie entstehen. Der praktische Teil der Arbeit basiert auf der theoretischen Auseinandersetzung und wird in diesem Dokument ausführlich beschrieben und dokumentiert. Zum Ende dieser Bachelorarbeit steht ein eigens erstelltes, vollständiges Videospiel, welches sich an den Charakteristiken des Arcade-Game Genres orientiert und eine schriftliche Ausarbeitung, welche dessen Entstehungsprozess, bezugnehmend auf bestehende Literatur dokumentiert

Struktur von Fixpunkten aus Prozeßgleichungen

In dieser Arbeit untersuchen wir die Prozeßgleichung $( (X(s) )_{s \in [0, 1)} ~ ( \sum_{i \in N} 1_{s \in I_i} * A_i(s) * X_i( B_i(s) ) + C(s) )_{s \in [0, 1)}$ in Hinblick auf Fixpunke mit Pfaden in D, dem Raum der cadlag-Funktionen. Das Standardbeispiel ist die Prozeßgleichung des Find-Algorithmus. Über die Betrachtung der endlichdimensionalen Marginalverteilungen erhalten wir die Existenz eines Prozesses X mit Pfaden in D, der die Prozeßgleichung erfüllt. Im Verlauf der Arbeit betrachten wir auch die stochastische Fixpunktgleichung $X ~ \sup_{i \in N} A_i * X_i + C$ für Zufallsgrößen mit Werten in $R^+$ und zeigen über ein Monotonieargument die Existenz eines Fixpunktes. Im Anhang dieser Arbeit untersuchen wir die Wasserstein-Metriken auf Wahrscheinlichkeitsmaßen. Wir zeigen die Vollständigkeit des Raumes der Wahrscheinlichkeitsmaße auf der Borel-sigma-Algebra eines separablen endlichdimensionalen Banachraumes und betrachten den Zusammenhang der schwachen Konvergenz mit der Konvergenz bezüglich der Wasserstein-Metriken

Implications from Responsible Human-Robot Interaction with Anthropomorphic Service Robots for Design Science

Accelerated by the COVID-19 pandemic, anthropomorphic service robots are continuously penetrating various domains of our daily lives. With this development, the urge for an interdisciplinary approach to responsibly design human-robot interaction (HRI), with particular attention to human dignity, privacy, compliance, and transparency, increases. This paper contributes to design science, in developing a new artifact, i.e., an interdisciplinary framework for designing responsible HRI with anthropomorphic service robots, which covers the three design science research cycles. Furthermore, we propose a multi-method approach by applying this interdisciplinary framework. Thereby, our finding offer implications for designing HRI in a responsible manner

Responsible Human-Robot Interaction with Anthropomorphic Service Robots: State of the Art of an Interdisciplinary Research Challenge

Anthropomorphic service robots are on the rise. The more capable they become and the more regular they are applied in real-world settings, the more critical becomes the responsible design of human-robot interaction (HRI) with special attention to human dignity, transparency, privacy, and robot compliance. In this paper we review the interdisciplinary state of the art relevant for the responsible design of HRI. Furthermore, directions for future research on the responsible design of HRI with anthropomorphic service robots are suggested

Taste preference, food neophobia and nutritional intake in children consuming a cows' milk exclusion diet: a prospective study.

BACKGROUND: Taste exposure in infancy is known to predict food preferences later in childhood. This is particularly relevant in children with cows' milk allergy who consume a substitute formula and/or a cows' milk exclusion (CME) diet early in life. This prospective study aimed to show whether there is a long-term effect of consuming a substitute formula and CME diet on taste preferences and dietary intake. METHODS: Children were predominantly recruited from two large birth cohort studies in the UK. Two groups were recruited: an experimental group of children who had consumed a CME diet during infancy and a control group who had consumed an unrestricted diet during infancy. Parents completed a food neophobia questionnaire and an estimated prospective food diary. Children completed a taste preference test and their growth was assessed. RESULTS: One hundred and one children with a mean age of 11.5 years were recruited (28 CME and 73 controls). Children in the CME group had a significantly higher preference for bitter taste than those in the control group (P < 0.05). There were significant differences between the groups with respect to the intake of some micronutrients, including riboflavin, iodine, sodium and selenium. Food neophobia did not differ between groups. Some 28% of the CME group were overweight/obese compared to 15% of the control group; however, this difference was not statistically significant. CONCLUSIONS: Consuming a substitute formula and/or a CME diet in infancy has a long-term effect on the preference for bitter taste. Differences exist with respect to the intake of some micronutrients, but not macronutrients. There was a nonsignificant trend towards being overweight and obese in children in the CME group