41 research outputs found
Diversifikationseffekte durch Small und Mid Caps?
In this paper, we analyze the potential benefits of international diversification with small and mid caps. Based on an empirical analysis of European large, small and mid cap stock indices, we find that small caps have relatively low correlations not only with large caps but also with each other. We show, that small cap stock returns cannot be spanned by large cap stock returns. Furthermore, we find that diversification in Europe is likely to be more effective with a combination of small and large caps than with large caps alone. In the paper, we present several robustness checks and show that our results are also valid in sub-periods as well as for upside and downside stock market moves. Moreover, we find that large cap returns are mainly driven by global factors whereas returns on small cap stocks are primarily driven by local and idiosyncratic factors. Furthermore, the different industry classification of large and small caps explain parts of our results.
Nonverbal Communication During Human-Robot Object Handover. Improving Predictability of Humanoid Robots by Gaze and Gestures in Close Interaction
Meyer zu Borgsen S. Nonverbal Communication During Human-Robot Object Handover. Improving Predictability of Humanoid Robots by Gaze and Gestures in Close Interaction. Bielefeld: Universität Bielefeld; 2020.This doctoral thesis investigates the influence of nonverbal communication on human-robot object handover. Handing objects to one another is an everyday activity where two individuals cooperatively interact. Such close interactions incorporate a lot of nonverbal communication in order to create alignment in space and time. Understanding and transferring communication cues to robots becomes more and more important as e.g. service robots are expected to closely interact with humans in the near future. Their tasks often include delivering and taking objects. Thus, handover scenarios play an important role in human-robot interaction. A lot of work in this field of research focuses on speed, accuracy, and predictability of the robot’s movement during object handover. Still, robots need to be enabled to closely interact with naive users and not only experts. In this work I present how nonverbal communication can be implemented in robots to facilitate smooth handovers. I conducted a study on people with different levels of experience exchanging objects with a humanoid robot. It became clear that especially users with only little experience in regard to interaction with robots rely heavily on the communication cues they are used to on the basis of former interactions with humans. I added different gestures with the second arm, not directly involved in the transfer, to analyze the influence on synchronization, predictability, and human acceptance. Handing an object has a special movement trajectory itself which has not only the purpose of bringing the object or hand to the position of exchange but also of socially signalizing the intention to exchange an object. Another common type of nonverbal communication is gaze. It allows guessing the focus of attention of an interaction partner and thus helps to predict the next action. In order to evaluate handover interaction performance between human and robot, I applied the developed concepts to the humanoid robot Meka M1. By adding the humanoid robot head named Floka Head to the system, I created the Floka humanoid, to implement gaze strategies that aim to increase predictability and user comfort. This thesis contributes to the field of human-robot object handover by presenting study outcomes and concepts along with an implementation of improved software modules resulting in a fully functional object handing humanoid robot from perception and prediction capabilities to behaviors enhanced and improved by features of nonverbal communication
False Consensus and the Role of Ambiguity in Predictions of Others’ Risk Preferences
Already in the 1930ies psychologists mentioned the tendency of people to see the self as the center of social judgment. This leads to egocentrically biased judgments when assessing others’ behavior. Since the first demonstration of this social projection bias in a study by Ross, Greene, and House (1977) a lot of studies followed. They show the effect in different contexts and the false consensus effect became a widely accepted phenomenon. In this paper we analyze the false consensus effect in a financial context. In two studies, we use simple lottery questions and ask subjects to state certainty equivalents for the own person and also to predict the average certainty equivalent of other participants. We find a strong correlation between the own judgment and the prediction of others’ judgments. As we use 50/50-lotteries and in addition ambiguous probabilities in our studies, we extend the scope of Gilovich (1990) to financial decisions. The false consensus effect is stronger in situations with ambiguity. We also asked participants to give an interval for the certainty equivalents, i.e. a lower bound that they think is not fallen short by more than 5 % of the participants and also an upper bound which is not exceeded by more than 5 %. We find that people strongly underestimate the variation in others’ risk preferences
Diversifikationseffekte durch small und mid caps? : Eine empirische Untersuchung basierend auf europäischen Aktienindizes
Im Laufe der Zeit ist die Korrelation von internationalen Aktienindizes tendenziell gestiegen, was die Möglichkeit einer Diversifikation von Aktieninvestments über verschiedene Länder einschränkt. Diese Erkenntnisse wurden allerdings erzielt auf der Basis von empirischen Analysen von Large Cap Indizes. Ob das Ergebnis allerdings auch für Small und Mid Cap Indizes vorliegt, ist bisher unbekannt. Ziel dieser Arbeit ist es deshalb zu überprüfen, ob bei Investition in Small und Mid Caps stärkere Diversifikationseffekte erzielt werden können. Die Arbeit beinhaltet eine empirische Analyse auf Basis von europäischen Aktienindizes, berechnet von den nationalen Börsen bzw. MSCI, für den Zeitraum von 1994 bis 2003. Unsere wesentlichen Ergebnisse können wie folgt zusammengefasst werden. Small Cap Indizes sind sowohl untereinander also auch mit Large Caps relativ niedrig korreliert. Allerdings waren alle Korrelationen in der Baisse signifikant höher als in der Hausse. Small Cap Indexrenditen können nicht vollständig durch Large Cap Indexrenditen dupliziert werden. Während Large Cap Renditen hauptsächlich durch globale Faktoren beeinflusst werden, spielen bei den Small Cap Renditen unternehmensindividuelle Faktoren eine größere Rolle. Außerdem bestehen Unterschiede in der Branchenzugehörigkeit zwischen Small und Large Caps. Eine Beimischung von Small und Mid Caps hat generell zu einer Senkung des Portfoliorisikos geführt
Investment decisions of private households and the role of financial advice
The following research questions are addressed in this thesis: 1. Is it possible to correctly evaluate other persons’ preferences? Which factors drive the ego-centric bias? (Chapter 3) 2. What does the typical household portfolio look like? What are determinants of households’ investment behavior? (Chapter 4) 3. Which factors drive the willingness to accept financial advice? (Chapter 5
ToBI - Team of Bielefeld: The Human-Robot Interaction System for RoboCup@Home 2014
Ziegler L, Wittrowski J, Meyer zu Borgsen S, Wachsmuth S. ToBI - Team of Bielefeld: The Human-Robot Interaction System for RoboCup@Home 2014. Presented at the RoboCup 2014, JoĂŁo Pessoa, Brasil
ToBI-Team of Bielefeld The Human-Robot Interaction System for RoboCup@Home 2016
Meyer zu Borgsen S, Korthals T, Wachsmuth S. ToBI-Team of Bielefeld The Human-Robot Interaction System for RoboCup@Home 2016. Presented at the RoboCup, Leipzig, Germany
ToBI - Team of Bielefeld A Human-Robot Interaction System for RoboCup@Home 2018
Wachsmuth S, Lier F, Meyer zu Borgsen S. ToBI - Team of Bielefeld A Human-Robot Interaction System for RoboCup@Home 2018. Presented at the RoboCup 2018, Montreal, Canada.The Team of Bielefeld (ToBI) was founded in 2009. The RoboCup team’s activities are embedded in a long-term research agenda towards human-robot interaction with laypersons in regular and smart home environments. The RoboCup@Home competition is an important benchmark and milestone for this goal in terms of robot capabilities as well as the system integration effort. In order to achieve a robust and stable system performance, we apply a systematic approach for reproducible robotic experimentation including automated tests. A second focus of research is the development of reusable robot behaviors and robot skills. By re-usability we mean both, the re-use in different robot tasks as well as the reuse across different platforms. For RoboCup 2018, we plan to enhance this approach for the standard platform Pepper which comes with certain requirements and limitations, like its own runtime and development ecosystem, limited computing resources onboard, or a limited range of sensor devices. We further introduce a simulation environment for the Pepper robot that is based on MORSE and allows to define additional artificial agents as human-like interaction partners. This is one of the key features for simulating complete RoboCup@Home tasks. In this paper, we will present a generic approach to these issues. System descriptions as well as build and deployment procedures are modeled in the Cognitive Interaction Toolkit. The overall framework inherently supports the idea of open research and offers direct access to reusable components and reproducible systems via a web-based catalo
ToBI-Team of Bielefeld The Human-Robot Interaction System for RoboCup@Home 2015
Meyer zu Borgsen S, Korthals T, Ziegler L, Wachsmuth S. ToBI-Team of Bielefeld The Human-Robot Interaction System for RoboCup@Home 2015. Presented at the RoboCup 2015, Hefei, China
ToBI-Team of Bielefeld The Human-Robot Interaction System for RoboCup@Home 2015
Meyer zu Borgsen S, Korthals T, Ziegler L, Wachsmuth S. ToBI-Team of Bielefeld The Human-Robot Interaction System for RoboCup@Home 2015. Presented at the RoboCup 2015, Hefei, China