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41.
We study parametric and non‐parametric approaches for assessing the accuracy and coverage of a population census based on dual system surveys. The two parametric approaches being considered are post‐stratification and logistic regression, which have been or will be implemented for the US Census dual system surveys. We show that the parametric model‐based approaches are generally biased unless the model is correctly specified. We then study a local post‐stratification approach based on a non‐parametric kernel estimate of the Census enumeration functions. We illustrate that the non‐parametric approach avoids the risk of model mis‐specification and is consistent under relatively weak conditions. The performances of these estimators are evaluated numerically via simulation studies and an empirical analysis based on the 2000 US Census post‐enumeration survey data.  相似文献   
42.
We investigate the impact of product market competition on returns to skills in Italy using a longitudinal dataset on individual working histories. This impact is identified using three exogenous shocks affecting competition: the unforeseen devaluation of the Lira in 1992, its return to a fixed exchange regime in 1996 and the market liberalisation in the utility and transport sectors in the late 1990s–early 2000s. We analyse how firm heterogeneity and shocks of different types and signs affect the impact of competition on skill premia. We find that opposite shocks have opposite effects: an increase (resp. decrease) in international competition increases (resp. decreases) skill premia. Moreover, international shocks have greater effects on medium sized firms, while domestic liberalisation shocks have greater effects on large incumbents.  相似文献   
43.
The consumption of maritime cruises is one of the most striking facets of the phenomenon of a new middle class emergence in Brazil. This study investigates the use of maritime cruises by emerging middle-class consumers to enact their new social status. Specifically, the research looks at ritualistic behaviour performed by consumers before, during, and after a cruise. The research uses a multi-method design characterised by a combination of ethnography and group discussions. The study contributes to enlarge McCracken’s typology of consumption rituals, showing how emerging consumers use the cruise as a rite of passage, during which they perform rituals of preparation, production, possession, and divestment. It also sheds light on specific rituals performed by consumers in order to transfer meanings from the cruise to their own selves. Finally, the findings suggest that consumption rituals in the context of social ascent may not have the transformative power of traditional rites.  相似文献   
44.
This study examines whether CEO duality affects the association between board independence and demand for higher quality audits, proxied by audit fee. The findings show that there is a positive association between board independence and audit fees. This result is consistent with findings of Carcello et al. (2002) that more independent boards demand higher audit quality and effort. However, this positive association is only present in firms without CEO duality, thus suggesting that CEO duality constrains board independence. The results support recommendations against CEO duality by showing that dominant CEOs may compromise the independence of their board of directors. Additionally, evidence is provided that board size (the number of directors on the board) is positively associated with audit fee pricing. This is consistent with prior studies that indicate that larger board sizes are associated with inefficiency and negative firm performance.  相似文献   
45.
As documented in the literature, the effects of firm size, financial leverage, and R&D expenditures on firm earnings are inclusive. Our hypothesis is that the inconsistent empirical results of such effects may be driven by the regression models implemented in data analysis. Using the quantile regression (QR) approach developed by Koenker and Basset (1978), this study analyses S&P 500 firms from 1996 to 2005. We find that the effects of firm size, financial leverage and R&D expenditures on firm earnings differ considerably across earnings quantiles. Comparing the results from the QR approach with those from the ordinary least squares (OLS) and least absolute deviation (LAD) methods, this study further explains the puzzling relationship between firm size, financial leverage, R&D expenditures and firm earnings.  相似文献   
46.
李孝明 《价值工程》2014,(12):219-220
为了快速、准确地计算渐开线圆柱齿轮的几何尺寸和测量尺寸公法线长度或者圆棒跨距,在没有齿轮设计软件的情况下,文章对应用Excel表来计算的方法进行了研究,其计算速度比用一般函数计算器提高数百倍,大大提高了齿轮设计人员和工艺人员的工作效率。  相似文献   
47.
This research investigates how the public of a middle‐income country, Thailand, values ecosystem services associated with irrigated rice agriculture using a choice experiment. The results show a significant willingness to pay for services such as drought mitigation, water quality and the environment and maintenance of rural lifestyles and rice landscapes. The iterative procedure developed to fully analyze the incidence of attribute nonattendance (ANA) improved the model fit when compared with a multinomial logit model or an ANA model with potentially only one attribute ignored at a time (ANA‐1). Moreover, the inferred probability of the class of respondents having attended all attributes was 45%, compared to 9% with ANA‐1 model. However, it also suggests that 55% of the respondents made their choices by considering only two of the five attributes. Finally, this research also suggests that failing to consider ANA does not change the public ranking of scenarios contrasted by the services they would provide but would overestimate the WTP for these scenarios.  相似文献   
48.
49.
高大平房仓储粮第一年秋、冬低温季节利用小功率风机进行下行式机械通风降低基础粮温;储存稳定期在确保储存安全的前提下,进入第2年、第3年秋冬季节则采用自然通风;气温上升季节对仓房实施隔热密闭、仓顶喷淋等一系列控温措施,在低能耗的情况下,可有效控制粮温,且大大减少了因通风产生水分散失而造成的储粮损耗.经过3年的储藏,损耗率低至1.42‰,且稻谷品质达到要求,降低储粮保管费用.  相似文献   
50.
This paper examines dynamic patterns of land use, capital investments and wages in agriculture using farm panel data from Indonesia. The empirical analysis shows that with an increase in real wages that prevailed in both agricultural and non-agricultural sectors in rural areas, relatively larger farmers increased the size of operational farm land by renting in land as well as used more hired-in machines through machine rental and/or service providers, which induces the substitution of labor by machines. Machines and land are complementary and, consistently, the inverse farm size-productivity relationship tends to be reversed among relatively large holders. The results support growing (diminishing) advantage of large (small) farms in the presence of rapidly rising real wages and have food security policy implications to many Asian countries where real wages are rapidly rising and small farms are predominant.  相似文献   
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