浅析Cache命中率与块的大小之间的关系

本篇文章简单介绍了Cache对计算机的重要性,由此引出了Cache命中率,并着重讨论了Cache块的大小对Cache命中率的影响。     

Analysis of treatment response data from eligibility designs

In this paper, we develop and compare two alternative approaches for calculating the effect of the actual intake when treatments are randomized, but compliance with the assignment in the treatment arm is less than perfect for reasons that are correlated with the outcome. The approaches are based on different identification assumptions about these unobserved confounders. In the first approach, which stems from [Sommer, A., Zeger, S., 1991. On estimating efficacy in clinical trials. Statistics in Medicine 10, 45–52], the unobserved confounders are modeled by a discrete indicator variable that represents subject-type, defined in terms of the potential intake in the face of each possible assignment. In the second approach, confounding is modeled without reference to subject-type in the spirit of the Roy model. Because the two models are non-nested, and model comparison and assessment of the approaches in a real data setting is one of our central goals, we formulate the discussion from a Bayesian perspective, comparing the two models in terms of marginal likelihoods and Bayes factors, and in terms of inferences about the treatment effects. The latter we calculate from a predictive perspective in a way that is different from that in the literature, where typically only a point summary of that effect is calculated. Our real data analysis focuses on the JOBS II eligibility trial that was implemented to test the effectiveness of a job search seminar in decreasing the negative mental health effects commonly associated with job loss. We provide a comparative analysis of the data from the two approaches with prior distributions that are both reasonable in the context of the data and comparable across the model specifications. We show that the approaches can lead to different evaluations of the treatment.     

Revealing Differences in Willingness to Pay due to the Dimensionality of Stated Choice Designs: An Initial Assessment

Stated choice (SC) methods are now a widely accepted data paradigm in the study of the choice responses of agents. Their popularity has spawned an industry of applications in fields as diverse as transportation, environmental science, health economics and policy, marketing, political science and econometrics. With rare exception, empirical studies have used a single SC design, in which the numbers of attributes, alternatives, choice sets, attribute levels and ranges have been fixed across the entire design. As a consequence the opportunity to investigate the influence of design dimensionality on behavioural response has been denied. Accumulated wisdom has promoted a large number of positions on what design features are specifically challenging for respondents; and although a number of studies have assessed the influence of subsets of design dimensions, there exists no single study (that we are aware of) that has systematically varied all of the main dimensions of SC experiments. This paper reports some initial findings on what influences, in aggregate, specific design configurations have on the mean willingness to pay for specific attributes using a Design of Designs (DoD) SC experiment in which the ‘attributes’ of the design are the design dimensions themselves. The design dimensions that are varied are the number of choice sets presented, the number of alternatives in each choice set, the number of attributes per alternative, the number of levels of each attribute and the range of attribute levels. The empirical evidence, using a sample of respondents in Sydney choosing amongst trip attribute bundles for their car commuting trip, suggests that, within the boundaries of design dimensionality investigated, mean estimates of WTP for travel time savings in the aggregate cover a range that is appropriate for reporting a global mean and a set of meaningful values for sensitivity testing in project appraisal and demand prediction. When these aggregated mean estimates are conditioned on all design dimensions we do not find any systematic differences due to specific design dimensions; however when each design dimension is assessed without controlling for the other dimensions we find evidence to support differences in aggregate mean WTP attributable to the number of attributes per alternative and the number of alternatives in a choice set. Research funded under the Australian Research Council Large Grants Scheme, Grant A00103962.     

What Drives Shareholder Reaction and Wealth Effect in Block Trades? Evidence from the Warsaw Stock Exchange

The main objective of this article is to present the determinants of shareholder reaction to block trades and their wealth effect on the Warsaw Stock Exchange. The positive abnormal returns obtained for the entire sample indicate that block trades create shareholder value. Shareholders reacted positively to block trades without a control transfer in the Polish market, and their reaction was stronger than in the US market. Abnormal returns of block trades concluded at a discount were twice as high as those for the entire sample. Moreover, cross-border block trades had a negative impact on shareholder value creation, as did financial investors as an acquirer. However, cumulative average abnormal returns (CAARs) were driven up by the relative power of minority shareholders (ocean) prior to the transaction. The absolute size of the block acquired by an investor was also observed to have a positive impact on price rises and abnormal returns.     

Efficiencies for optimum designs when transforming the response in nonlinear models with nonconstant variance

Often the responses from mechanistic models have to be transformed to achieve error distributions that are symmetric and have constant variance. Because of the nature of the relationship between the response and the mechanistic model, it is necessary to transform both sides of the model. Expressions are given for the parameter sensitivities in the transformed model and examples given of optimum designs for particular values of λ, together with the efficiency of these designs as λ varies. Approaches to finding designs robust to variations in λ are indicated and exemplified.     

空管系统任务模块分配并行性的模糊优化研究

利用模糊集分析的方法，根据贴近度函数和择近原则，建立了空中交通管理系统多任务模块并行度的度量模型，为提高空管系统中多任务处理的并行性提供了一种的方法；并举例阐述了该方法，在空管系统软件模块并行性分配中的应用并分析了结果。     

苯乙烯嵌段共聚物的生产技术及市场前景

本文介绍了苯乙烯嵌段共聚物(SBC)的生产方法及其技术进展,分析了国内外SBC的生产消费现状及发展前景,提出了发展我国SBC生产的一些建议.     

Block Trade Price Asymmetry and Changes in Depth: Evidence from the Australian Stock Exchange

This paper examines the price response to large block transactions on the Australian Stock Exchange during the 1999 sample period. We find asymmetry in the price reaction between buyer‐ and seller‐initiated trades with respect to size and resiliency following the trade. We extend previous research by examining order book changes surrounding block trades and relating price effects to changes in book depth. Purchases are associated with persistent order book imbalance, while the sales imbalance is insignificant. Cross‐sectional analysis demonstrates that price resiliency following a trade is related to the speed at which limit orders arrive to replenish book depth.     

宁镇扬经济板块现代物流服务业一体化发展战略

从宁镇扬现代物流服务业一体化的必要性进行分析,进而对宁镇扬地区物流服务业一体化的有利条件进行了较详细的阐述;最后,对如何构建宁镇扬板块现代物流服务业的一体化提出了对策和建议。     

居民水价递增阶梯结构与政策效应研究

This article takes the price structure of two-levels as a case study to analyze the relationship between the threshold or price of the tariff and IBTs’ policy effects,in which residents’ expenditure on water is also discussed .It shows that both the threshold and price affect the policy effects,and the volatility of residents’ expenditure on water depends on the demand intensity of consumers.