• 한국인구학
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• 제24권2호
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• pp.117-147
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• 2001

이 연구는 북한의 1994년 인구센서스 자료에 나타난 성 및 연령구조를 분석하기 위한 것이다. 이 연구에서는 우선 1994년 1월 남북분단 이후 최초로 실시된 북한 인구센서스의 배경과 특징을 설명하고, 아울러 가용한 자료들을 활용하여 북한인구의 추세와 현황을 개관하였다. 이 연구의 초점은 북한 인구센서스 자료의 성 및 연령구조와 관련된 몇 가지 문제를 제기하고, 이를 재검토하는 데 맞추어져 있다. 북한이 제공하고 있는 인구자료에는 16-25세 연령집단의 남녀 성비가 비정상적으로 낮게 나타나고 있다. 또한 총인구규모에 있어서도 연령별 인구합계와 지역별 인구합계가 다르게 기재되어 있다. 이 연구에서는 북한 인구센서스 자료에 나타난 성 및 연령구조의 특징과 정확도를 파악하기 위하여 몇 가지 지수들이 작성되었으며, 이러한 작업을 토대로 북한인구의 성 및 연령별 분포를 재구성하여 수정인구를 추정하는 시도가 이루어졌다.

• Imaging Science in Dentistry
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• 제43권2호
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• pp.71-75
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• 2013

Purpose: This study was performed to determine the position of the mental foramen relative to the apices of the teeth based on panoramic radiographs in a Moroccan population. We also analyzed gender differences and the symmetry of location within individuals. Materials and Methods: Seven hundred ninety-four panoramic radiographs were evaluated with regard to the location and symmetry of the mental foramina in male and female subjects. The results were analyzed using Pearson's ${\chi}^2$ and Fisher's exact test. Results: Of the 794 panoramic radiographs, 377 met the inclusion criteria for at least one side. The mental foramen was located just below the apex of the second premolar in 62.7% of the patients and between the first and second premolars in 30%. It was symmetrically located in 79%. No statistically significant differences were found between males and females in the position and symmetry of the mental foramen. Conclusion: The most common position for the mental foramen in this sample was in line with the second premolar.

• The Journal of Advanced Prosthodontics
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• 제4권2호
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• pp.72-75
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• 2012

PURPOSE. This study evaluated the existence of golden proportion between the widths of the maxillary and mandibular anterior teeth in Indian population. MATERIALS AND METHODS. The clinical tooth width measurements were recorded with the digital vernier calipers on 576 patients of both sexes in the age group of 21 - 30 years. Flexible ruler was used to determine the width of maxillary and mandibular anterior teeth on the patients by the same operator. The data obtained was statistically analyzed using paired student t-test (${\alpha}$=.05). RESULTS. The golden proportion was not found between the width of the right central and lateral incisors in 53% of women and 47% of men. The results revealed the golden percentage was rather inconstant in terms of relative tooth width. CONCLUSION. The golden proportion is an inappropriate method to relate the successive widths of the maxillary anterior teeth in Indian population.

• Journal of Life Science
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• 제12권1호
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• pp.27-32
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• 2002

Enzyme electrophoresis was used to estimate genetic diversity and population structure of maize, Zea mays L. (Graminales) in Korea. In nine populations, fourteen of the 24 loci (58.3 %) showed detectable polymorphism. Genetic diversity (0.205) was higher than average values for species with similar life history traits. Although our data are relatively small and the landraces not direct ancestors of cultivar, apparently the domestication process has eroded the levels of genetic variation of maize. The recent cultivars were found to have fewer alleles per locus (1.42 vs. 1.56), fewer alleles per polymorphic locus (2.27 vs. 2.33), lower percent polymorphic locus (33.3% vs. 41.7%), and lower diversity (0.159 vs. 0.185) than landraces. These genetic diversity parameters indicated that the cultivar populations were genetically depauperate relative to landlaces. The GST value of nine populations was 0.239. Nearly 76% of the total genetic diversity in Zea mays was apportioned within populations. The indirect estimate of gene new based on mean GST was moderate (Nm=0.80).

• Journal of Plant Biology
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• 제20권3호
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• pp.119-126
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• 1977

The maximum relative growth rate of algae treated with Zinc was shown as follows: 15, 8, 6, 3 and -5% per day for the rather sensitive Chlorella sp. populations, or 14, 7, 5 and 4% per day for the Pleurococcus sp. populations, and 22, 20, 13, 9 and 7% per day for the more resistant Scenedesmus spinosus populations, respectively for the culture medium with 0, 1, 5, 10 and 20 ppm of Zinc treatment. With mixed cultures of Chlorella sp. and Scenedesmus spinosus populations, the growth of the Chlorella sp. population overcame that of the S. spinomsus population from the cultures treated with relatively low concentration of Zinc. On the contrary, the population growth of the latter resistant species overcame that of the former sensitive species when the concentration of Zinc was above 5 ppm Zn of the medium. This paper describes the results of further investigations of the effects evaluated by direct cell counts method, optical density comparisons, oxygen production and consumption determinations and the measurements of the fate of Zinc treated in the solutions.

• Communications for Statistical Applications and Methods
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• 제31권3호
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• pp.291-308
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• 2024

The current article discusses ratio type exponential estimators for estimating the mean of a finite population in sample surveys. The estimators uses robust regression's Huber M-estimation function, and their bias as well as mean squared error expressions are derived. It was campared with Kadilar, Candan, and Cingi (Hacet J Math Stat, 36, 181-188, 2007) estimators. The circumstances under which the suggested estimators perform better than competing estimators are discussed. Five different population datasets with a well recognized outlier have been widely used in numerical and simulation-based research. These thorough studies seek to provide strong proof to back up our claims by carefully assessing and validating the theoretical results reported in our study. The estimators that have been proposed are intended to significantly improve both the efficiency and accuracy of estimating the mean of a finite population. As a result, the results that are obtained from statistical analyses will be more reliable and precise.

• Communications for Statistical Applications and Methods
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• 제10권2호
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• pp.535-543
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• 2003

A ranked set sample version of the sign test is proposed for testing hypotheses concerning the quantiles of a population characteristic by Kaur, et. al(2002). In this paper, we proposed the ranked set sample Wilcoxon signed rank test for quantiles under equal allocation. We obtain the asymptotic property and the asymptotic relative efficiencies of the proposed test statistic with respect to Wilcoxon signed rank test of simple random sample for quantiles under equal allocation. We calculate the ARE of test statistics, the proposed test statistic is more efficient than simple random sampling for all quantiles. The relative advantage of ranked set sampling is greatest at the median and tapers off in the tails.

• 응용통계연구
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• 제24권3호
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• pp.445-453
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• 2011

Almost all small area estimations are obtained by minimizing the mean squared error. Recently relative error prediction methods have been developed and adapted to small area estimation. Usually the estimators obtained by using relative error prediction is called a shrinkage estimator. Especially when data set consists of large range values, the shrinkage estimator is known as having good statistical properties and an easy interpretation. In this paper we study the shrinkage estimators based on logistic regression type estimators for small area estimation. Some simulation studies are performed and the Economically Active Population Survey data of 2005 is used for comparison.

• Journal of Forest and Environmental Science
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• 제30권3호
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• pp.259-266
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• 2014

Stand Density Diagrams (SDD) are average stand-level models which graphically illustrate the relationship between yield, density and mortality throughout the various stages of forest development. These are useful tools for designing, displaying and evaluating alternative density regimes in even-aged forest ecosystems to achieve a desired future condition. This contribution presents an example of a SDD that has been constructed for teak forests of Karnataka in southern India. The relationship between stand density, dominant height, quadratic mean diameter, relative spacing and stand volume is represented in one graph. The relative spacing index was used to characterize the population density. Two equations were fitted simultaneously to the data collected from 27 sample plots measured annually for three years: one relates quadratic mean diameter with stand density and dominant height while the other relates total stand volume with quadratic mean diameter, stand density and dominant height.

• Communications for Statistical Applications and Methods
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• 제13권2호
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• pp.243-254
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• 2006

The relative frequency of order statistics is investigated for independent and identically distributed (i.i.d.) random variables. Specifically, it is shown that the probability $Pr\{X_{[s]}=x\}$ is no less than the probability $Pr\{X_{[r]}=x\}$ at any point $x{\geqq}x_0$ when r$X_{[r]}$ denotes the r-th order statistic of an i.i.d. discrete random vector and $x_0$ depends on the population probability distribution. A similar result for i.i.d. continuous random vectors is also presented.