Bayesian estimation of P (Y<X) from Burr-type X model containing spurious observations

We consider the problem of estimating R=P(Y<X) when X and Y are independent Burr-type X random variables. We assume that the sample from each population contains one spurious observation. Bayes estimates are derived for exchangeable and identifiable cases. Monte Carlo simulation is carried out to compare the bias and the expected loss of R.     

Determinants of Portfolio Efficiency Losses in US Self-directed Pension Accounts

This empirical study evaluates the magnitude of efficiency losses of household portfolio choices in self-directed pension accounts (SDAs). It uses data from the Survey of Consumer Finances (SCF). The determinants of the magnitude of efficiency losses across household investors are investigated in detail. The findings of this study lend empirical support to the belief that the magnitude of efficiency losses for household investors differs with the different demographic characteristics and investment propensities. In particular, household investors with long-investment horizons, with more autonomy of choices in their SDAs, or with the tendency to select high levels of portfolio risk in SDAs are more vulnerable to efficiency losses. Factors to predict the levels of portfolio risk maintained by household investors in their SDAs are also explored.     

油画语言与油画材料的有机结合:艺术与超越艺术

文章围绕写实油画的教学,从技术层面到艺术层面,从艺术层面到当今艺术专业学生的现实处境,探讨了艺术与市场、大众和社会联系的可能性,在现实与理想之间,提示了在社会主义市场经济条件下,艺术教育值得思考的问题。     

论羌族民间美术产品的开发与利用

羌族民间美术,历史悠久,自成体系,是一个未被充分开发和利用的艺术资源。文章从政府对羌族民间美术的重视与支持、专家学者的研究、商品经济与旅游的结合这三个方面,对羌族民间美术产品的开发与利用进行了探讨,以期有益于对羌族民间美术的传承与发展。     

On diagnostic checking of the autoregressive conditional intensity model

The autoregressive conditional intensity model proposed by Russell (1998) is a promising option for fitting multivariate high frequency irregularly spaced data. The authors acknowledge the validity of this model by showing the independence of its generalized residuals, a crucial assumption of the model formulation not readily recognized by researchers. The authors derive the large‐sample distribution of the autocorrelations of the generalized residual series and use it to construct a goodness‐of‐fit test for the model. Empirical results compare the performance of their test with other off‐the‐shelf tests such as the Ljung–Box test. They illustrate the use of their test with transaction records of the HSBC stock.     

鸭病康防治鸭传染病的研究(二)——对鸭霍乱的防治报告

将鸭霍乱病鸭、可疑鸭和试验性感染禽多杀性巴氏杆菌的鸭随机分为对照组和试验组,用鸭病康口服液进行疗效试验研究,并用西药进行对比。结果表明:鸭病康口服液对试验性感染禽多杀性巴氏杆菌鸭的保护率分别为100％、80％、40％;对可疑鸭的预防效果与土霉素无明显差异(P>0.05);对急性病鸭的治愈率不及肌注卡那霉素(P<0.05)。     

The Causes and Consequences of Immigrant Labour in the Construction Sector in Malaysia

Malaysian construction is highly dependant on immigrant labour; immigrants account for nearly 70 per cent of its workforce. Although they have aided the sector's rapid expansion, it has not been without costs. This paper examines the impact of immigrant labour on construction. The main finding is that immigrants, being largely unskilled, did not contribute to skill formation. Instead, they accumulated skills on‐the‐job, which were lost when they returned home. There was no evidence that immigrants displaced domestic workers since they were concentrated in jobs rejected by Malaysians. Furthermore, unlike in earlier periods, legal immigrants were no longer a cheap option, given the regulations governing their employment. They were not used to cut costs per se, but were used because domestic workers were not available in sufficient numbers. Despite the large immigrant presence, the general wage level increased, though admittedly not as rapidly as it might have in their absence. The reliance on immigrant workers has increased the need for supervision and quality control, thereby reducing the savings in cost; nonetheless, immigrants have helped keep costs in check. Surprisingly, rising wages and the continued shortage of labour have not led to a widespread adoption of labour‐saving methods. This is partly because productivity increases have managed to outpace wage increases, though this advantage is petering out. Also, immigrant presence has kept wages, as a proportion of total costs, manageable. The over reliance of the sector on immigrant labour is not desirable, especially since the majority is drawn from one source ‐ Indonesia. Any disruption of supply from this source can undermine the Malaysian economy. To avoid this, Malaysia must vary its source of immigrant labour and intensify efforts to attract domestic workers by improving conditions in construction.     

薏米中微量有机锗测定的研究

依据二甲氧基羟基苯芴酮与锗的显色原理,用分光光度法对薏米中微量锗进行测定.研究了于HAC-NaAC的缓冲体系,在溴化十六烷基三甲铵(CTMAB)存在下,二甲氧基羟基苯芴酮与Ge(Ⅳ)形成红色络合物,其络合物的最大吸收波长为529nm,Ge(Ⅳ)在0-1.0ug/mL范围内符合比尔定律.拟定方法具有较好的选择性,多数金属离子不干扰检测,用于薏米中微量有机锗的测定,该方法简单可靠,并获得满意的分析结果.     

The Opportunity Cost of Admission Preferences at Elite Universities*

Objective. This study examines how preferences for different types of applicants for admission to elite universities influence the number and composition of admitted students. Methods. Previous research with these NSCE data employed logistic regression analysis to link information on the admission decision for 124,374 applications to applicants' SAT scores, race, athletic ability, and legacy status, among other variables. Here we use micro simulations to illustrate what the effects might be if one were to withdraw preferences for different student groups. Results. Eliminating affirmative action would substantially reduce the share of African Americans and Hispanics among admitted students. Preferences for athletes and legacies, however, only mildly displace members of minority groups. Conclusions. Elite colleges and universities extend preferences to many types of students, yet affirmative action is the one most surrounded by controversy.     

Child Support Obligations and Low‐Income Fathers

Using the 1994–1998 waves of the Current Population Survey—Child Support Supplement (N =5,387), the aims of this study are to document child support obligation rates of nonresident fathers, to examine the effect of the obligation rate on child support compliance, and to calculate the trade‐off between fathers’ financial responsibility and children's well‐being, paying particular attention to low‐income fathers. The results indicate that low‐income fathers have high child support obligation rates, which significantly reduce their child support compliance. Although lowering the obligation rate for these fathers may improve their compliance, it does not fully offset the lowered obligation amounts and leads to a 30% net payment loss for welfare mothers and a 43% loss for nonwelfare mothers. Policy implications are discussed.