cphVB: A System for Automated Runtime Optimization and Parallelization of Vectorized Applications

Modern processor architectures, in addition to having still more cores, also require still more consideration to memory-layout in order to run at full capacity. The usefulness of most languages is deprecating as their abstractions, structures or objects are hard to map onto modern processor architectures efficiently. The work in this paper introduces a new abstract machine framework, cphVB, that enables vector oriented high-level programming languages to map onto a broad range of architectures efficiently. The idea is to close the gap between high-level languages and hardware optimized low-level implementations. By translating high-level vector operations into an intermediate vector bytecode, cphVB enables specialized vector engines to efficiently execute the vector operations. The primary success parameters are to maintain a complete abstraction from low-level details and to provide efficient code execution across different, modern, processors. We evaluate the presented design through a setup that targets multi-core CPU architectures. We evaluate the performance of the implementation using Python implementations of well-known algorithms: a jacobi solver, a kNN search, a shallow water simulation and a synthetic stencil simulation. All demonstrate good performance

Restoration after bereavement

Journal ArticleThe death of a spouse in later life, after many years of marriage is one of the most common of all major stressful life transitions. After age 65, 32% of the U.S. population is widowed (14% for men and 45% for women) with this increasing to 46% after age 75 and 66% after the age of 85 (U.S. Bureau of the Census, 2000)

Does Tax Matter? Evidence on Executive Compensation After 162(m)\u27s Repeal

As part of the most sweeping federal tax reform in a generation, the Tax Cuts and Jobs Act (“TCJA”) radically altered the tax treatment of compensation paid to senior executives of public companies. Prior to the TCJA, payment of such compensation in excess of one million dollars was non-deductible except to the extent the compensation was performance-based. The TCJA eliminated the exception so that all senior executive compensation above one million dollars is now non-deductible regardless of whether it is performance-based or not.This reform provides a natural experiment to study the role of tax law in influencing managerial pay decisions, an issue that has been debated for decades by scholars and policymakers. Did the elimination of the performance-based pay exception influence senior executive compensation decisions?Using a novel empirical design, we find no evidence that the repeal of the performance-based pay exception changed the most significant and salient compensation features, namely the proportion of performance-based pay to total pay and the overall amount of pay. On the other hand, when we move from headline compensation features to smaller technical ones, our data suggests that the tax change has had a significant influence. This suggests that tax rules may be only consequential in shaping executive compensation when no one else is paying attention otherwise