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221.
    
The Consumer Price Index (CPI) approximates changes in the costs of household consumption assuming the constant utility (COLI, Cost of Living Index). In practice, the Laspeyres price index is used to measure the CPI despite the fact that many economists consider the superlative indices to be the best approximation of COLI. The Fisher index is one of the superlative indices and additionally it satisfies most of tests from the axiomatic price index theory. Nevertheless, the Fisher price index makes use of current-period expenditure data and its usefulness in CPI measurement is limited. In this article, we verify the utility of using the Lowe, Young, and AG Mean indices for Fisher price index approximation. We confirm this utility in a simulation study and we provide an empirical proof.  相似文献   
222.
    
ABSTRACT

We consider a model consisting of two fluid queues driven by the same background continuous-time Markov chain, such that the rates of change of the fluid in the second queue depend on whether the first queue is empty or not: when the first queue is nonempty, the content of the second queue increases, and when the first queue is empty, the content of the second queue decreases.

We analyze the stationary distribution of this tandem model using operator-analytic methods. The various densities (or Laplace–Stieltjes transforms thereof) and probability masses involved in this stationary distribution are expressed in terms of the stationary distribution of some embedded process. To find the latter from the (known) transition kernel, we propose a numerical procedure based on discretization and truncation. For some examples we show the method works well, although its performance is clearly affected by the quality of these approximations, both in terms of accuracy and run time.  相似文献   
223.
    
Confidence interval (CI) for a standard deviation in a normal distribution, based on pivotal quantity with a Chi-square distribution, is considered. As a measure of CI quality, the ratio of its endpoints is taken. There are given formulas for sample sizes so that this ratio does not exceed a fixed value. Both equally tailed and minimum ratio of endpoint CIs are considered.  相似文献   
224.
    
Abstract

We study the almost sure convergence of weighted sums of ratios of independent random variables satisfying some general, mild conditions. The obtained results are applied to exact laws for order statistics. An exact law for independent random variables which are nonidentically distributed is also proved and applied to ratios of adjacent order statistics for a sample of uniformly distributed random variables.  相似文献   
225.
Until recently Poland has been considered a country to emigrate from. However, the situation is now beginning to change, and Poland is becoming an immigration country. This also refers to student migration. Polish universities are becoming increasingly attractive to foreign students, who are mainly of Ukrainian origin. They only began to promote their services abroad in 2005 and their foreign student population growth dynamic is one of the highest in the world. The study was conducted in the Opolskie Voivodeship, the first region in Poland where systematic action was taken to address depopulation, and the steps to counteract population decline were included in its strategic policies. One of the objectives of such policies was to stimulate immigration. For this reason, it was decided that the Opolskie Voivodeship might serve as a lab to study migration processes, including the inflow of foreign students.  相似文献   
226.
Conservation of biodiversity in urban areas has become crucial to urban green area management. There are several legislative solutions for preservation of species and habitats in cities. One of them is ‘ecological lands’ – a low-restrictive form of protected areas in Poland. We aimed to assess their efficiency in vascular flora biodiversity conservation in the urban environment in Poznań (W Poland; 550,000 inhabitants). We hypothesized that ecological lands which cover <2% of the city area comprise over 50% of taxonomic diversity and over 90% of functional trait-level range of the vascular flora. Analysis of five ecological lands, which covered 1.8% of the whole city area confirmed our hypothesis. In ecological lands studied, we found 564 species of vascular plants, which is 52.9% of the whole city flora. These species belonged to 23 of 29 phytosociological classes represented in the whole city (73.9%). Functional trait distributions in ecological lands studied comprised from 95.8 to 100% of trait distributions in the flora of the whole city. Ecological lands seem to be a good way for conservation of biodiversity in urban areas. The legislative simplicity and low restrictiveness for both land management and recreational utility make ecological lands a much easier form of nature conservation which may be adapted to other cities for more efficient biodiversity management.  相似文献   
227.
This article explores media discourse of ageing, taking the example of Poland and relating it to a broader discussion of ageing policy. The discourse in news magazines appears both to reflect and create attitudes towards older people, which in turn has implications for ageing policy. To reveal the nature of these attitudes, we use a method of attitudinal positioning. The study analyzes articles that appeared in the four largest Polish weekly opinion news magazines, in the 2004–2007 period. Various domains in the discourse of ageing are identified, yet only the family and market domains seem to be described in exclusively positive terms: the authors discuss the implications of this for ageing policy.  相似文献   
228.
Assuming absolute continuity of marginals, we give the distribution for sums of dependent random variables from some class of Archimedean copulas and the marginal distribution functions of all order statistics. We use conditional independence structure of random variables from this class of Archimedean copulas and Laplace transform. Additionally, we present an application of our results to \({{\mathrm{VaR}}}\) estimation for sums of data from Archimedean copulas.  相似文献   
229.
    
The aim of the study was to assess the incidence and severity of the frailty syndrome assessed with the Edmonton Frailty Scale. This is a cross-sectional study conducted among 382 patients (236 men and 146 women, mean age 71.9?years). The Edmonton Frailty Scale was administered during the patient’s admission to the hospital. The Polish adaptation was performed using the standard methodology. The Cronbach’s alpha coefficient for the whole Edmonton Frailty Scale was 0.709. The mean correlation between positions and the overall result was r?=?0.180. There were no statistically significant differences between women and men in the area of Edmonton Frailty Scale mean score (p?70?years than for those?<70?years (p?相似文献   
230.
    
In this paper bivariate vectors of discrete aging and alternative aging intensities are introduced. Using these vector-valued functions we present some results about bivariate discrete distributions.  相似文献   
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