基于动态贝叶斯网络的邻近下穿隧道深基坑施工风险分析

为了减小邻近既有下穿隧道深基坑施工风险及灾害损失,科学预防施工安全事故,提出了一种基于动态贝叶斯网络（DBN）的深基坑施工风险分析模型。首先,运用BWM（best worst method）确定准则的权重;其次,基于关联规则挖掘风险因素间的相互关系,并以此构建DBN结构模型;最后,以新建厦门北站地下一层社会连廊深基坑工程为例,对提出的方法进行有效性和适用性检验。结果表明：基坑围护结构的安全度在静态被评为“较高”和“极高”的概率分别为34.6%和36.1%,且此结果随着输入风险证据发生动态变化,运用反向推理也能迅速找出围护桩渗水风险;提出的模型能明确邻近既有下穿隧道深基坑施工风险传递过程中的关键风险点,并能进行动态风险预测以及事故后致因诊断,从而实现邻近既有下穿隧道深基坑施工风险的动态管控。所提出的优化DBN模型对工前风险评估、先验分析和风险诊断有较好的适用性和较高的准确性,可为邻近既有隧道深基坑施工过程中的安全管控提供有效的决策支持,大幅提高风险控制效率。     

Measuring Lifetime Redistribution in Dutch Occupational Pensions

Summary  This paper assesses how the Dutch system of occupational pensions redistributes between and within generations. The approach in this paper deviates from the usual approach by incorporating the full life cycle in the measurements, rather than only the annual effects. In order to quantify redistribution, we use the level of educational attainment, gender and age to classify the pension fund population. For all groups distinguished, we measure in present value terms the average net benefit from participating in occupational pensions. The results indicate a sizable redistribution from males to females and from low educated to higher educated workers. On a lifetime basis, the impact of intergenerational transfers is modest. I am grateful to the two anonymous referees, Ed Westerhout, Casper van Ewijk, Lex Meijdam, Yvonne Adema and Peter Kooiman for their helpful comments on earlier drafts of this paper, and to Andre Nibbelink for his valuable computational assistance.     

Fractional integration in daily stock market indices at Jordan's Amman stock exchange

Using daily data on five sectoral indices from 2006 to 2014, this paper aims to investigate the possibility of fractional integration in sectoral returns (and their volatility measures) at Jordan's Amman stock exchange (ASE). Empirical analysis, using the log-periodogram (LP) and local whittle (LW) based semi-parametric fractional differencing techniques suggest that all sectoral returns at ASE exhibit short memory. However, in the case of volatility measures, we found evidence of long memory. Following the recent literature that argues that structural breaks in a time series could also explain the presence of long memory, we tested the volatility measures for the presence of structural breaks. We found that long memory in some volatility measures could be attributed to the presence of structural breaks. Furthermore, using impulse response functions (IRF) based on ARFIMA, we found that shocks to sectoral returns at ASE exhibit short run persistence, whereas shocks to volatility measures display long run persistence.     

Pattern mining in tourist attraction visits through association rule learning on Bluetooth tracking data: A case study of Ghent,Belgium

The rapid evolution of information and positioning technologies, and their increasing adoption in tourism management practices allows for new and challenging research avenues. This paper presents an empirical case study on the mining of association rules in tourist attraction visits, registered for 15 days by the Bluetooth tracking methodology. This way, this paper aims to be a methodological contribution to the field of spatiotemporal tourism behavior research by demonstrating the potential of ad-hoc sensing networks in the non-participatory measurement of small-scale movements. An extensive filtering procedure is followed by an exploratory analysis, analyzing the discovered associations for different visitor segments and additionally visualizing them in ‘visit pattern maps’. Despite the limited duration of the tracking period, we were able to discover interesting associations and further identified a tendency of visitors to rarely combine visits in the center with visits outside of the city center. We conclude by discussing both the potential of the employed methodology as well as its further issues.     

Optimal interest-rate rules and inflation stabilization versus price-level stabilization

This paper compares the properties of interest-rate rules such as simple Taylor rules and rules that respond to price-level fluctuations (called Wicksellian rules) in a basic forward-looking model. By introducing appropriate history dependence in policy, Wicksellian rules perform better than optimal Taylor rules in terms of welfare, robustness to alternative shock processes, and are less prone to equilibrium indeterminacy. A simple Wicksellian rule augmented with a high degree of interest rate inertia resembles a robustly optimal rule, i.e., a monetary policy rule that implements the optimal plan and that is also completely robust to the specification of exogenous shock processes.     

Monetary regime choice in Singapore: Would a Taylor rule outperform exchange-rate management?

A DSGE–VAR approach was adopted to examine the managed exchange-rate system at work in Singapore and to ask if the country had any reason to fear floating the exchange rate and adopting a Taylor rule. The results showed that, in terms of overall inflation volatility, the exchange rate rule had a comparative advantage over the Taylor rule when export-price shocks were the major sources of real volatility while a Taylor rule was preferable when domestic productivity shocks were dominant. The exchange-rate rule also dominated the Taylor rule for reducing inflation persistence.     

NO‐ARBITRAGE PRICING UNDER SYSTEMIC RISK: ACCOUNTING FOR CROSS‐OWNERSHIP

We generalize Merton’s asset valuation approach to systems of multiple financial firms where cross‐ownership of equities and liabilities is present. The liabilities, which may include debts and derivatives, can be of differing seniority. We derive equations for the prices of equities and recovery claims under no‐arbitrage. An existence result and a uniqueness result are proven. Examples and an algorithm for the simultaneous calculation of all no‐arbitrage prices are provided. A result on capital structure irrelevance for groups of firms regarding externally held claims is discussed, as well as financial leverage and systemic risk caused by cross‐ownership.     

再论中华存在和发展的根本规律

根据内因和外因关系的原理,中华存在和发展的根本规律表现在两个方面:构成中华整体的三个基本方面即中华自然、中华民族和中华文化之间的对立统一;中华作为一个局部与世界这个整体之间的对立统一。中华的存在和发展,是通过中华根本规律的这两个基本方面互相依存、互相渗透和互相转化来实现的。     

有限政府与有效政府:道德规范构建中的国家与社会

本文对道德规范构建中的国家、社会和个人三者关系问题进行初步探讨,认为政府在道德规范构建中应努力达到有限政府和有效政府相结合的时代要求。     

THE DYNAMIC PROPERTIES OF ALTERNATIVE ASSUMPTIONS ON PRICE ADJUSTMENT IN NEW KEYNESIAN MODELS

This paper presents a classification of the different new Phillips curves existing in the literature as a set of choices based on three assumptions: the choice of the structure of price adjustments (Calvo or Taylor), the presence of backward indexation and the type of price contracts (fixed prices or predetermined prices). The paper suggests study of the dynamic properties of each specification, following different monetary shocks on the growth rate of the money stock. We develop the analytical form of the price dynamics, and we display graphics for the responses of prices, output and inflation. We show that the choice made for each of the three assumptions has a strong influence on the dynamic properties. Notably, the choice of the price structure, while often considered as unimportant, is indeed the most influential choice concerning the dynamic responses of output and inflation.