Finite nonparametric grach model for foreign exchange volatility

GARCH model has been commonly used to describe the volatility of foreign exchange returns, which typically depends on returns many lags before, While the GARCH model provides a simple geometric decaying structure for persistence in time, it restricts tiie impact of variables to Quadratic functions. A finite nonparametric GARCH model is proposed that allows the variables' impact to be a smooth function of any form. A direct local polynomial estimation method for this finite GARCH model is proposed based on results on proportional additive model, and is applied to the German Mark (DEM)/US Dollar (USD) daily returns data. Estimators uf both the decaying rate and the impact function are obtained. Diagnostics show satisfactory out-of-sampie prediction based on the proposed model, which helps to better understand the dynamics of foreign exchange volatility.     

A Bivariate Generalization of Gamma Distribution

In this article, a bivariate generalisation of the gamma distribution is proposed by using an unsymmetrical bivariate characteristic function; an extension to the non central case also receives attention. The probability density functions of the product and ratio of the correlated components of this distribution are also derived. The benefits of introducing this generalized bivariate gamma distribution and the distributions of the product and the ratio of its components will be demonstrated by graphical representations of their density functions. An example of this generalized bivariate gamma distribution to rainfall data for two specific districts in the North West province is also given to illustrate the greater versatility of the new distribution.     

关于零级超球级数的平均值

本文得出了零级超球级数的对数级和对数下级与其在椭圆上的平均值的关系式。     

Counter-geographies: The campaign against rationalisation of agricultural research stations in New South Wales, Australia

This paper discusses an example of community action mounted in a rural region of New South Wales, Australia, in response to proposals by the State Government to rationalise agricultural research stations operated by the Department of Primary Industries. Informed by a Foucaultian understanding of power and the concept of governmentality, neoliberalism is theorised as being the broad governmental context in which rationalisation proposals were put forward. Recent literature drawing on this theoretical perspective has emphasised that neoliberalism is enacted through a relationship of power, and is not monolithic or inevitable. Neoliberalism is always negotiated by those seeking to govern and those who are the object of such governmental actions. This paper analyses how plans to rationalise publicly funded agricultural research stations were opposed by those seeking to keep research facilities open in the case study area. The paper discusses the methods and scope of community action and, drawing on interviews, identifies a series of discourses articulated by campaigners. Non-local actors were depicted as uncaring and insensitive. In contrast, campaigners discussed the emergence of a ‘city-country divide’ in domestic politics; the need for specialist agricultural knowledge given the region's unique geographical location; and local impacts of an economic, social and emotional nature. Central were discourses of maintaining community, tradition, and continuity in unique local places defined by their climate, biophysical environment and economy. These were ‘counter-geographies’ that sought (successfully, it would transpire) to disrupt the state's imagined geography of a homogenous and flexible administrative space in which research services could be relocated wherever most efficient. Important too were embodied resistances to the way rural industries and people were subjected. Campaigners refused to accept preferred codes of neoliberal behaviour (particularly mobility and rationality) and instead demanded respect for their careers, families and communities. Important considerations are suggested for further research on impacts and negotiations of neoliberalism. This study particularly highlights the successes—as well as contradictions and limitations—of arguments that construct rural places as socialised, unique and unfairly treated (by governments), in opposition to metropolitan dominance and ‘placeless’ neoliberalism.     

De-aliasing effects using semifoldover techniques

Semifoldover designs, obtained by semifolding a regular two-level factorial design, have been discussed recently in the literature. In this article, with the use of indicator functions, we investigate various semifoldover designs that are obtained from a general two-level factorial design. We discuss when a main factor or a two-factor interaction can be de-aliased from their aliased two-factor interactions, and extend some of the existing results from regular designs to non-regular designs. Finally, we present some examples to illustrate the results developed here.     

Biased Bootstrap Methods for Reducing the Effects of Contamination

Contamination of a sampled distribution, for example by a heavy-tailed distribution, can degrade the performance of a statistical estimator. We suggest a general approach to alleviating this problem, using a version of the weighted bootstrap. The idea is to 'tilt' away from the contaminated distribution by a given (but arbitrary) amount, in a direction that minimizes a measure of the new distribution's dispersion. This theoretical proposal has a simple empirical version, which results in each data value being assigned a weight according to an assessment of its influence on dispersion. Importantly, distance can be measured directly in terms of the likely level of contamination, without reference to an empirical measure of scale. This makes the procedure particularly attractive for use in multivariate problems. It has several forms, depending on the definitions taken for dispersion and for distance between distributions. Examples of dispersion measures include variance and generalizations based on high order moments. Practicable measures of the distance between distributions may be based on power divergence, which includes Hellinger and Kullback–Leibler distances. The resulting location estimator has a smooth, redescending influence curve and appears to avoid computational difficulties that are typically associated with redescending estimators. Its breakdown point can be located at any desired value ε∈ (0, ½) simply by 'trimming' to a known distance (depending only on ε and the choice of distance measure) from the empirical distribution. The estimator has an affine equivariant multivariate form. Further, the general method is applicable to a range of statistical problems, including regression.     

区域和谐与地方政府区际行政行为创新研究

区际行政行为研究,针对的是地方政府行为中与其他地区有互动关系,对其他地区具有影响作用的一部分行为,地方政府区际行政行为的合作与否,直接关系区域之间的和谐共荣。当前,扭曲的区际行政行为设立起无形的行政壁垒,已经成为制约区域经济一体化的瓶颈,弹奏着区域发展的不和谐音符。分析地方政府博弈心理,认为地方政府区际行政行为创新是促进区域和谐发展的有效"解决之道"。     

Robust models in probability sampling

In the estimation of a population mean or total from a random sample, certain methods based on linear models are known to be automatically design consistent, regardless of how well the underlying model describes the population. A sufficient condition is identified for this type of robustness to model failure; the condition, which we call 'internal bias calibration', relates to the combination of a model and the method used to fit it. Included among the internally bias-calibrated models, in addition to the aforementioned linear models, are certain canonical link generalized linear models and nonparametric regressions constructed from them by a particular style of local likelihood fitting. Other models can often be made robust by using a suboptimal fitting method. Thus the class of model-based, but design consistent, analyses is enlarged to include more realistic models for certain types of survey variable such as binary indicators and counts. Particular applications discussed are the estimation of the size of a population subdomain, as arises in tax auditing for example, and the estimation of a bootstrap tail probability.     

Proof of Toft's Conjecture: Every Graph Containing No Fully Odd K4 is 3-Colorable

A fully odd K₄ is a subdivision of K₄ such that each of the six edges of the K₄ is subdivided into a path of odd length. In 1974, Toft conjectured that every graph containing no fully odd K₄ can be vertex-colored with three colors. The purpose of this paper is to prove Toft's conjecture.     

酒店管理专业“订单式”培养模式研究——新建地方本科院校培养模式改革探索之一

新建的地方本科院校在激烈的市场竞争中怎样站稳脚跟,找到自己合适的生存和发展空间,是目前的当务之急。而良好的教学培养模式是其生存的基础,必须进行培养模式的改革和创新。"订单式"培养模式的建立是适合新建本科院校,尤其是这些院校的一些新建应用型专业的特点,对其进行研究和实施具有重要的理论和现实意义。