The Effect of Reputation on Selling Prices in Auctions

In economic approaches it is often argued that reputation considerations influence the behavior of individuals or firms and that reputation influences the outcome of markets. Empirical evidence is rare though. In this contribution we argue that a positive reputation of sellers should have an effect on selling prices. Analyzing auctions of popular DVDs at eBay we, indeed, find support for this hypothesis. Secondary, we unmask the myth that it is promising for eBay sellers to let their auction end at the evening, when many potential buyers may be online

Spectral approach to axisymmetric evolution of Einstein's equations

We present a new formulation of Einstein's equations for an axisymmetric spacetime with vanishing twist in vacuum. We propose a fully constrained scheme and use spherical polar coordinates. A general problem for this choice is the occurrence of coordinate singularities on the axis of symmetry and at the origin. Spherical harmonics are manifestly regular on the axis and hence take care of that issue automatically. In addition a spectral approach has computational advantages when the equations are implemented. Therefore we spectrally decompose all the variables in the appropriate harmonics. A central point in the formulation is the gauge choice. One of our results is that the commonly used maximal-isothermal gauge turns out to be incompatible with tensor harmonic expansions, and we introduce a new gauge that is better suited. We also address the regularisation of the coordinate singularity at the origin.Comment: 6 pages, based on a talk given by one of the authors at the Spanish Relativity Meeting ERE14 in Valencia, published versio

Optimal contracts for central bankers: calls on inflation

We consider a framework featuring a central bank, private and financial agents as well as a financial market. The central bank's objective is to maximize a functional, which measures the classical trade-off between output and inflation plus income from the sales of inflation linked calls minus payments for the liabilities that the inflation linked calls produce at maturity. Private agents have rational expectations and financial agents are averse against inflation risk. Following this route, we explain demand for inflation linked calls on the financial market from a no-arbitrage assumption and derive pricing formulas for inflation linked calls, which lead to a supply-demand equilibrium. We then study the consequences that the sales of inflation linked calls have on the observed inflation rate and price level. Similar as in Walsh (1995) we find that the inflationary bias is significantly reduced, and hence that markets for inflation linked calls provide a mechanism to implement inflation contracts as discussed in the classical literature

Wake Structures and Surface Patterns of the DrivAer Notchback Car Model under Side Wind Conditions

The flow field topology of passenger cars considerably changes under side wind conditions. This changes the surface pressure, aerodynamic force, and drag and performance of a vehicle. In this study, the flow field of a generic passenger vehicle is investigated based on three different side wind angles. The study aimed to identify vortical structures causing changes in the rear pressure distribution. The notchback section of the DrivAer model is evaluated on a scale of 1:4. The wind tunnel tests are conducted in a closed section with a splitter plate at a Reynolds number of 3 million. The side wind angles are 0∘ , 5∘ , and 10∘ . The three-dimensional and time-averaged flow field downstream direction of the model is captured by a stereoscopic particle image velocimetry system performed at several measurement planes. These flow field data are complemented by surface flow visualizations performed on the entire model. The combined approaches provide a comprehensive insight into the flow field at the frontal and side wind inflows. The flow without side wind is almost symmetrical. Longitudinal vortices are evident along the downstream direction of the A-pillar, the C-pillars, the middle part of the rear window, and the base surface. In addition, there is a ring vortex downstream of the vehicle base. The side wind completely changes the flow field. The asymmetric topology is dominated by the windward C-pillar vortex, the leeward A-pillar vortex, and other base vortices. Based on the location of the vortices and the pressure distributions measured in earlier studies, it can be concluded that the vortices identified in the wake are responsible for the local minima of pressure, increasing the vehicle drag

On the effects of changing mortality patterns on investment, labour and consumption under uncertainty

In this paper we extend the consumption-investment life cycle model for an uncertain-lived agent, proposed by Richard (1974), to allow for exible labor supply. We further study the consumption, labor supply and portfolio decisions of an agent facing age-dependent mortality risk, as presented by UK actuarial life tables spanning the time period from 1951-2060 (including mortality forecasts). We find that historical changes in mortality produces significant changes in portfolio investment (more risk taking), labour (decrease of hours) and consumption level (shift to higher level) contributing up to 5% to GDP growth during the period from 1980 until 2010

An analysis of the fish pool market in the context of seasonality and stochastic convenience yield

On the basis of a popular two-factor approach applied in commodity markets, we develop a model featuring seasonality and study futures contracts written on fresh farmed salmon, which have been actively traded at the Fish Pool market in Norway since 2006. The model is estimated by means of Kalman filtering, using a rich data set of contracts with different maturities traded at Fish Pool between 01/01/2010 and 24/04/2014. The results are then discussed in the context of other commodity markets, specifically live cattle, which is a substitute. We show that the seasonally adjusted model proposed in this article describes the behavior of salmon price very well. More importantly we show that seasonality exists in the salmon futures market. This is highly important in pricing of contingent claims, designing hedging strategies, and making real investment decisions in marine resources

The Effect of Reputation on Selling Prices in Auctions

In economic approaches it is often argued that reputation considerations influence the behavior of individuals or firms and that reputation influences the outcome of markets. Empirical evidence is rare though. In this contribution we argue that a positive reputation of sellers should have an effect on selling prices. Analyzing auctions of popular DVDs at eBay we, indeed, find support for this hypothesis. Secondary, we unmask the myth that it is promising for eBay sellers to let their auction end at the evening, when many potential buyers may be online.Reputation; eBay feedback system; auction

Could you hand me the efficiency section, please? Newspaper circulation and local government efficiency in Norway

Whenever citizens want their elected officials to employ funds efficiently, they are in need of information in order to establish accountability. We develop an agency model with imperfect monitoring where newspapers provide voters with this information. The model predicts that an informed electorate is more likely to hold an incumbent accountable. Using panel data on Norwegian municipalities we show that increases in local newspaper circulation are associated with higher levels of local government efficiency as measured by an index introduced by the Norwegian authorities.media, newspapers, local government, public sector efficiency, Norway

An Empirical Study on Risk Taking in Tournaments

Individuals faced by a tournament can oftentimes not only choose their effort level, but also the risk level of their strategy. There are some theoretical contributions on risk taking in tournaments, which mainly point out disadvantages with respect to exerted effort. Empirical evidence is rare. In this paper we analyze risk taking behavior of professional soccer coaches. We find that risk taking concerning the kind of observed substitutions is, indeed, relevant. However, risk taking does not pay off.