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This paper investigates the selection of third-party logistics providers (3PLs) based on the best prices offered by them. The focus is on outbound logistics where 3PLs must have their own distribution centres for storage and picking activities. They must also have suitable trucks for distribution to different small-scale customers. The motivation for this paper is a case study from Germany in which a furniture company with hundreds of small customers in ten zones is seeking one or more 3PLs to do the distribution. A mathematical programming model was built based on integer programming where demand per order can be expressed using exponential distribution in each customer zone. The main contribution of this paper is that it finds the best 3PLs based on the different pricing methods of the various providers; this means including the location problem indirectly using the new integer programming model. The model takes into consideration three different methods of pricing based on the offers of five 3PLs. These different methods make it difficult for the decision makers to choose the best solution, especially if specific trends in demand are expected in the future for some customer zones. The results show that future increases in demand in terms of the number of orders or order size could affect the optimal solution. The best pricing method with the lowest variability in cost over time is selected. [ABSTRACT FROM AUTHOR]

Liquidity risk is the risk that an asset cannot always be sold without causing a fall in its price because of a lack of demand for this asset. Many empirical studies examining liquidity premia have focused on government bonds. In this paper, we specifically investigate the yield differentials between liquid and illiquid German covered bonds by considering the yields of traditional Pfandbrief bonds and Jumbo Pfandbrief bonds with different maturities. In terms of credit risk the spread between the yields of these two types of covered bonds should be zero. Moreover, assuming that the liquidity risk premium is a stationary variable the yields of Pfandbrief bonds and Jumbo Pfandbrief bonds (which seem to be integrated of order one) should be cointegrated. We make use of the methodology proposed in the related field of fractional integrated models to conduct our empirical analysis. Due to the 2008–2009 global financial crisis, it also seems to be appropriate to consider structural change. To the extent that the European Central Bank has started to purchase covered bonds under the crisis pressure, our empirical evidence would have a high relevance for monetary policymakers as far as the liquidity risk is concerned. Here, our results indicate fractionally cointegrated yields before and after the crisis, while the degree of integration of the spread increases strongly during the crisis. [ABSTRACT FROM AUTHOR]

There are essentially two alternatives to analyse the impacts of tax reform proposals on risk-taking: the two-asset model and the certainty equivalent approach. Here risk-taking is defined in terms of the certainty equivalent approach. The paper discusses the effects of current tax reform proposals in the Federal Republic of Germany and in the United States with respect to risk-taking. Among others it is shown that there are unambiguous effects of the reform proposals as far as the upper income class is considered. Furthermore, the paper studies some impacts of the transition from the FRG-schedule T88 (coming into force at the beginning of 1988) to an intended schedule characterized by a linearly increasing marginal tax rate. [ABSTRACT FROM AUTHOR]

We present the problem of planning mobile tours of inspectors on German motorways to enforce the payment of the toll for heavy good trucks. This is a special type of vehicle routing problem with the objective to conduct as good inspections as possible on the complete network. In addition, we developed a personalized crew rostering model, to schedule the crews of the tours. The planning of daily tours and the rostering are combined in a novel integrated approach and formulated as a complex and large scale Integer Program. The main focus of this paper extends our previous publications on how different requirements for the rostering can be modeled in detail. The second focus is on a bi-criteria analysis of the planning problem to find the balance between the control quality and the roster acceptance. Finally, computational results on real-world instances show the practicability of our method and how different input parameters influence the problem complexity. [ABSTRACT FROM AUTHOR]

The energy sector continues to undergo substantial structural changes. Currently, the expansion of renewable energy sources and the decentralisation of energy supply lead to new players entering the market who pursue different objectives and have different preferences. Thus, multiple and usually conflicting targets need to be considered. Moreover, recent public reactions towards infrastructure projects highlight the importance of considering public acceptance as a key dimension of decision making in the energy sector. As a result, decision processes grow more complex at all levels from political to strategic, tactical and operational decisions in companies. We therefore present an approach combining power systems analysis considering grid constraints and multi-criteria decision analysis. The approach focusses on multi-dimensional sensitivity analyses allowing for simultaneous variations of the different preference parameters determined within the decision analysis aimed at facilitating preference elicitation and consensus building in group decisions. The focus of the paper is the demonstration of the presented approach for a power generation and transmission planning case study in the context of the energy transition in Germany. [ABSTRACT FROM AUTHOR]

This study investigates the extent to which intraday price jumps and co-jumps in cryptocurrency markets stem from the release of macroeconomic news from the U.S., Germany and Japan. Using 5-min frequency prices for Bitcoin and Ethereum quoted against the U.S. dollar over the 2016–2019 period, we find that intraday price jumps are three times more frequent in Ethereum than in Bitcoin. More importantly, we show that jumps in Ethereum are more sensitive to macroeconomic news than jumps in Bitcoin, and that U.S. news releases exhibit higher influence on jumps in both cryptocurrencies than German and Japanese news announcements. We also find that co-jumps among Bitcoin and Ethereum are scarce and tend be associated only with a few U.S. news announcements, and in particular those related to the unemployment rate, new home sales, housing starts and Fed Beige Book. [ABSTRACT FROM AUTHOR]

This study uses data from the German Socio-Economic Panel to analyze peer effects in risk preferences. Empirical evidence on the impact of peer groups on individual willingness to take risks ('peer effects') is very limited so far as causality is hard to establish. To establish a causal relationship between individual and community risk preferences, we use an instrumental variables approach where we track the impact of the East–West migration after the German reunification. We find strong support for peer effects in risk preferences. Peer effects seem particularly relevant for women, less educated individuals, the young population, parents, and married individuals. Individuals with higher social interaction tend to have stronger peer effects. Our findings shed light on the origin and stability of risk tolerance and, more generally, on the determinants of economic preferences. [ABSTRACT FROM AUTHOR]

Comments on the works of the Gesellschaft für Mathematik, Ökonomie und Operations Research (GMÖOR), a scientific society in Germany. Objective of the society; Role of the society in bringing together scientists of completely different backgrounds; Highlights of the Symposium on Operations Research, an important European conference in the fields mentioned.