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971.
I analyze German top income mobility using micro‐level panel data of personal income tax returns which are highly representative for top income taxpayers for the years 2001–06. Top income mobility is assessed in three dimensions: (i) persistence in top income fractiles and its stability over time, (ii) measures of individual mobility that are not dependent on the fractile size: the degree of mobility between equally sized groups and mobility in ranks, and (iii) mobility's impact on top income shares. Persistence in top income fractiles is comparatively high and fairly stable across the analyzed period. Top income recipients are less prone to downward mobility and see less variation in annual ranks than less rich tax units. Mobility's impact on income concentration is moderate. The top percentile's share is reduced by roughly 5 percent over six years.  相似文献   
972.
It is a well‐known criticism that if the distribution of wealth is highly concentrated, survey data are hardly reliable when it comes to analyzing the richest parts of society. This paper addresses this criticism by providing a general rationale of the underlying methodological problem as well as by proposing a specific methodological approach tailored to correcting the arising bias. We illustrate the latter approach by using Austrian data from the Household Finance and Consumption Survey. Specifically, we identify suitable parameter combinations by using a series of maximum‐likelihood estimates and appropriate goodness‐of‐fit tests to avoid arbitrariness with respect to the fitting of the Pareto distribution. Our results suggest that the alleged non‐observation bias is considerable, accounting for about one quarter of total net wealth in the case of Austria. The method developed in this paper can easily be applied to other countries where survey data on wealth are available.  相似文献   
973.
Tracking is widely used in secondary schools around the world. Some countries put more emphasis on the use of performance to place students into tracks (e.g. the Netherlands), while in other countries parents have more influence on the track their child will go to (e.g. Germany). This article examines whether selection into tracks based on performance has an effect on the relation between tracking and student performance and educational opportunities. Using data from the Programme for International Student Assessment for around 185 000 students in 31 countries, different estimation models are compared. The results indicate that a highly differentiated system is best for performance when schools always consider prior performance when deciding on student acceptance. In systems with a few tracks, there is no such impact. Equality of opportunity is best provided for in a system with many tracks when schools always consider prior performance.  相似文献   
974.
Using online platforms to deliver educational content, some institutions have developed blended courses that combine the advantages of online instruction with traditional face-to-face (F2F) teaching. This study compares accounting student performance and satisfaction in two blended formats with similar content and design, i.e. F2F+ vs. Online+ courses. It also assesses the characteristics of students who choose the latter option over F2F+ courses. Students in four advanced accounting subjects were surveyed and their course performance was obtained. Results indicate that the main determinants of students’ decision to register for an Online+ course are retaking the course, increased weekly work hours, and belief that this type of blended course facilitates learning. Results show that students in advanced accounting courses with equivalent content and design perform similarly and have the same level of course satisfaction across course delivery formats, as hypothesized under equivalency theory.  相似文献   
975.
Statistical analyses on actual data depict operational risk as an extremely heavy-tailed phenomenon, able to generate losses so extreme as to suggest the use of infinite-mean models. But no loss can actually destroy more than the entire value of a bank or of a company, and this upper bound should be considered when dealing with tail-risk assessment. Introducing what we call the dual distribution, we show how to deal with heavy-tailed phenomena with a remote yet finite upper bound. We provide methods to compute relevant tail quantities such as the Expected Shortfall, which is not available under infinite-mean models, allowing adequate provisioning and capital allocation. This also permits a measurement of fragility. The main difference between our approach and a simple truncation is in the smoothness of the transformation between the original and the dual distribution. Our methodology is useful with apparently infinite-mean phenomena, as in the case of operational risk, but it can be applied in all those situations involving extreme fat tails and bounded support.  相似文献   
976.
In this study we investigate the duration of consumer price spells and price change patterns for Turkey by employing a comprehensive micro price data covering around 6,000 items over four years. In detail, we analyze how long typical price spell lasts and we investigate the size, frequency, distribution and synchronization of price changes. Compared to advanced economies, a higher frequency of price changes is estimated. Findings suggest substantial heterogeneity among sub-groups in terms of frequency and synchronization indicators. The mixed evidence of both state and time-dependent pricing is also relevant for Turkey, an emerging market economy.  相似文献   
977.
In this paper, we apply tools from random matrix theory (RMT) to estimates of correlations across the volatility of various assets in the S&P 500. The volatility inputs are estimated by modelling price fluctuations as a GARCH(1,1) process. The corresponding volatility correlation matrix is then constructed. It is found that the distribution of a significant number of eigenvalues of the volatility correlation matrix matches with the analytical result from RMT. Furthermore, the empirical estimates of short- and long-range correlations amongst eigenvalues, which are within RMT bounds, match with the analytical results for the Gaussian Orthogonal ensemble of RMT. To understand the information content of the largest eigenvectors, we estimate the contribution of the Global Industry Classification Standard industry groups to each eigenvector. In comparison with eigenvectors of correlation matrix for price fluctuations, only few of the largest eigenvectors of the volatility correlation matrix are dominated by a single industry group. We also study correlations between ‘volatility returns’ and log-volatility to find similar results.  相似文献   
978.
The analysis of sports data, in particular football match outcomes, has always produced an immense interest among the statisticians. In this paper, we adopt the generalized Poisson difference distribution (GPDD) to model the goal difference of football matches. We discuss the advantages of the proposed model over the Poisson difference (PD) model, which was also used for the same purpose. The GPDD model, like the PD model, is based on the goal difference in each game that allows us to account for the correlation without explicitly modelling it. The main advantage of the GPDD model is its flexibility in the tails by considering shorter as well as longer tails than the PD distribution. We carry out the analysis in a Bayesian framework in order to incorporate external information, such as historical knowledge or data, through the prior distributions. We model both the mean and the variance of the goal difference and show that such a model performs considerably better than a model with a fixed variance. Finally, the proposed model is fitted to the 2012–2013 Italian Serie A football data, and various model diagnostics are carried out to evaluate the performance of the model.  相似文献   
979.
为对炉膛结构进行优化,研究了不同炉膛长径比对甲醇燃烧室的温度分布及甲醛污染物排放的影响。以700kW甲醇锅炉为例,对甲醇燃料的燃烧过程进行数值模拟,将在Chemkin中得到的甲醇燃烧动力学反应机理导入Fluent软件中,并进行模拟分析。结果表明,炉膛最佳长径比为0.41时燃烧室内的燃烧最稳定,甲醛排放量达到最低值。  相似文献   
980.
This article presents the Kaleckian model of growth and distribution that sets a budget deficit ratio as an indicator of fiscal policy and examines the short- and long-run effects of an increase in budget deficits and a rise in income tax rates on the economy. The key short-run outcomes are as follows. First, expanded budget deficits have a positive effect on the rate of capacity utilization. Second, the tax rate for wage income does not affect the rate of capacity utilization, whereas the tax rate for capital income has a favorable impact on it. This result implies that raising the tax rate for capital income can be an important policy instrument for stimulating the economy. Third, we find that the economy exhibits a wage-led aggregate demand in the short run. The main long-run results are as follows. First, the effect of expanded budget deficits on the growth rate is ambiguous, since a higher debt burden negatively influences the rate of capacity utilization and hence economic growth, despite the increase in demand caused by government borrowing. A higher budget deficit ratio thus raises the growth rate only if a certain condition is satisfied. Second, the tax rate for capital income has a positive impact on the growth rate. Third, the economy shows a wage-led growth in the long run.  相似文献   
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