Pioneer anomaly: What can we learn from LISA?

The Doppler tracking data from two deep-space spacecraft, Pioneer 10 and 11, show an anomalous blueshift, which has been dubbed the "Pioneer anomaly". The effect is most commonly interpreted as a real deceleration of the spacecraft - an interpretation that faces serious challenges from planetary ephemerides. The Pioneer anomaly could as well indicate an unknown effect on the radio signal itself. Several authors have made suggestions how such a blueshift could be related to cosmology. We consider this interpretation of the Pioneer anomaly and study the impact of an anomalous blueshift on the Laser Interferometer Space Antenna (LISA), a planned joint ESA-NASA mission aiming at the detection of gravitational waves. The relative frequency shift (proportional to the light travel time) for the LISA arm length is estimated to 10E-16, which is much bigger than the expected amplitude of gravitational waves. The anomalous blueshift enters the LISA signal in two ways, as a small term folded with the gravitational wave signal, and as larger term at low frequencies. A detail analysis shows that both contributions remain undetectable and do not impair the gravitational-wave detection. This suggests that the Pioneer anomaly will have to be tested in the outer Solar system regardless if the effect is caused by an anomalous blueshift or by a real force.Comment: 19 pages, 4 figures. Talk given by D. Defrere at the conference "Lasers, Clocks, and Drag-Free", ZARM, Bremen, Germany, 30 May - 1 June 200

Note on tax enforcement and transfer pricing manipulation

This note proposes the segregation of independent endogenous and exogenous components of tax penalty probability to introduce a formal demonstration that enforcement and tax penalties are negatively related with income shifting. JEL F23; H26.Comment: 8 page

Resource Access with Variably Typed Return

Peer reviewedPreprin

JEqualityGen: Generating Equality and Hashing Methods

Manually implementing equals (for object comparisons) and hashCode (for object hashing) methods in large software projects is tedious and error-prone. This is due to many special cases, such as field shadowing, comparison between different types, or cyclic object graphs. Here, we present JEqualityGen, a source code generator that automatically derives implementations of these methods. JEqualityGen proceeds in two states: it first uses source code reflection in MetaAspectJ to generate aspects that contain the method implementations, before it uses weaving on the bytecode level to insert these into the target application. JEqualityGen generates not only correct, but efficient source code that on a typical large-scale Java application exhibits a performance improvement of more than two orders of magnitude in the equality operations generated, compared to an existing system based on runtime reflection. JEqualityGen achieves this by generating runtime profiling code that collects data. This enables it to generate optimised method implementations in a second round

Probabilistic Intra-Retinal Layer Segmentation in 3-D OCT Images Using Global Shape Regularization

With the introduction of spectral-domain optical coherence tomography (OCT), resulting in a significant increase in acquisition speed, the fast and accurate segmentation of 3-D OCT scans has become evermore important. This paper presents a novel probabilistic approach, that models the appearance of retinal layers as well as the global shape variations of layer boundaries. Given an OCT scan, the full posterior distribution over segmentations is approximately inferred using a variational method enabling efficient probabilistic inference in terms of computationally tractable model components: Segmenting a full 3-D volume takes around a minute. Accurate segmentations demonstrate the benefit of using global shape regularization: We segmented 35 fovea-centered 3-D volumes with an average unsigned error of 2.46 $\pm$ 0.22 {\mu}m as well as 80 normal and 66 glaucomatous 2-D circular scans with errors of 2.92 $\pm$ 0.53 {\mu}m and 4.09 $\pm$ 0.98 {\mu}m respectively. Furthermore, we utilized the inferred posterior distribution to rate the quality of the segmentation, point out potentially erroneous regions and discriminate normal from pathological scans. No pre- or postprocessing was required and we used the same set of parameters for all data sets, underlining the robustness and out-of-the-box nature of our approach.Comment: Accepted for publication in Medical Image Analysis (MIA), Elsevie

The Economic Consequences of Foreigner Rules in National Sports Leagues

This paper provides a contest model of a professional team sports league and analyzes the impact of a restriction on foreign players. It shows that a league with binding restrictions on foreign talent for all clubs is more balanced than a league without binding restrictions on foreign talent. Moreover, the wage level of domestic (foreign) talent is higher (lower) in a league with a binding restriction on foreign players. Finally, a tighter restriction on foreign players increases profits of all clubs.Team Sports Leagues, UEFA's Homegrown Rule, FIFA's 6+5 Rule, Competitive Balance, Player Salaries