The quantum communication complexity of the pointer chasing problem: the bit version

We consider the two-party quantum communication complexity of the bit version of the pointer chasing problem, originally studied by Klauck, Nayak, Ta-Shma and Zuckerman [KNTZ01]. We show that in any quantum protocol for this problem, the two players must exchange Δ(n/k4) qubits. This improves the previous best bound of Δ( n/22O(k)) in [KNTZ01], and comes significantly closer to the best upper bounds known O(n+k log n) (classical deterministic [PRV01]) and O(k log n+ n/k (log[k/2](n)+log k)) (classical randomized [KNTZ01]). Our proof uses a round elimination argument with correlated input generation, making better use of the information theoretic tools than in previous papers

Competitive Effects of Partial Ownership: Financial Interest and Corporate Control

In this article, we set up an economic framework for analyzing the competitive effects of partial ownership interests. We have three main goals. First, we conceptually derive and explain the competitive effects of partial ownership, explaining its key elements and drawing analogies to the key ideas behind the analysis of horizontal mergers. Second, we present a general framework for evaluating the competitive effects of partial ownership that is analogous to, but at the same time recognizes key differences in the standard analysis for evaluating horizontal mergers. Third, we examine several methods of quantifying these competitive effects

Methodological aspects of the SAVE data set

This paper describes the general design of the SAVE survey: the design of the questionnaire, inter-viewer and interviewee motivation, and the sampling designs of the various subsamples collected in 2001 and 2003. It discusses the representativeness of the data, explains the construction of weights, and provides probit regressions to analyze potential selectivity problems. The paper finishes by discussing implications for the use of the SAVE data in various estimation procedures.

Methodological aspects of the SAVE data set

This paper describes the general design of the SAVE survey: the design of the questionnaire, inter-viewer and interviewee motivation, and the sampling designs of the various subsamples collected in 2001 and 2003. It discusses the representativeness of the data, explains the construction of weights, and provides probit regressions to analyse potential selectivity problems. The paper finishes by discussing implications for the use of the SAVE data in various estimation procedures.

Polynomial-Time Fence Insertion for Structured Programs

To enhance performance, common processors feature relaxed memory models that reorder instructions. However, the correctness of concurrent programs is often dependent on the preservation of the program order of certain instructions. Thus, the instruction set architectures offer memory fences. Using fences is a subtle task with performance and correctness implications: using too few can compromise correctness and using too many can hinder performance. Thus, fence insertion algorithms that given the required program orders can automatically find the optimum fencing can enhance the ease of programming, reliability, and performance of concurrent programs. In this paper, we consider the class of programs with structured branch and loop statements and present a greedy and polynomial-time optimum fence insertion algorithm. The algorithm incrementally reduces fence insertion for a control-flow graph to fence insertion for a set of paths. In addition, we show that the minimum fence insertion problem with multiple types of fence instructions is NP-hard even for straight-line programs

The Colour of the Cats

China has experimented with two strategies of reform of its state-owned enterprises (SOE). One is diversification of SOEs’ ownership through introducing non-state sources of investment. Another is to improve the management of SOEs by granting SOEs’ managers autonomy and their employees profit incentives. Utilising a data set on 680 SOEs over 1980-94, we tested the relative effectiveness of two kinds of reform measures. Our results show that ownership diversification had a significant impact on the performance of SOEs while efforts to improve SOE’s management had very little effect. Moreover, the impact of ownership diversification on SOE’s economic performance was as strong as that of enhancing product market competition.

Financial Efficiency and the Ownership of Czech Firms

In this paper we analyze the evolution of firm financial efficiency in the Czech Repub-lic. Using a large panel of more than 400,000 Czech firm/years we study whether firms fully utilize their resources, how firm financial efficiency evolves over time, and how firm financial efficiency is determined by ownership structure. We employ a panel ver-sion of a stochastic production frontier model for the period 1996–2007 with time-invariant efficiency. We differentiate among various degrees of ownership concentra-tion and their domestic or foreign origin. In a two-stage set-up we estimate the degree of firm inefficiency and then we estimate the effect of ownership structure on the distance from the efficiency frontier. Our results support the hypothesis that concentration and foreign ownership are positively related to financial efficiency.financial efficiency, ownership structure, firms, panel data, stochastic frontier