• 제목/요약/키워드: Normal Distributions

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Asymptotic Relative Efficiencies of Chaudhuri′s Estimators for the Multivariate One Sample Location Problem

  • Park, Kyungmee
    • Communications for Statistical Applications and Methods
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    • 제8권3호
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    • pp.875-883
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    • 2001
  • We derive the asymptotic relative efficiencies in two special cases of Chaudhuri's estimators for the multivariate one sample problem. And we compare those two when observations are independent and identically distributed from a family of spherically symmetric distributions including normal distributions.

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안성천 유역의 BOD농도 확률분포 특성 (Characteristics of Probability Distribution of BOD Concentration in Anseong Stream Watershed)

  • 김경섭;안태진
    • 한국물환경학회지
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    • 제25권3호
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    • pp.425-431
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    • 2009
  • It is very important to know the probability distribution of water-quality constituents for water-quality control and management of rivers and reservoirs effectively. The probability distribution of BOD in Anseong Stream was analyzed in this paper using Kolmogorov-Smirnov test which is widely used goodness-of-fit method. It was known that the distribution of BOD in Anseong Stream is closer to Log-normal, Gamma and Weibull distributions than Normal distribution. Normal distribution can be partially applied depending on significance level, but Log-normal, Gamma and Weibull distributions can be used in any significance level. Also the estimated Log-normal distribution of BOD at Jinwi3 station was to be compared with the measured in 2001, 2002 and 2003 years. It was revealed that the estimated probability distribution of BOD at Jinwi3 follows a theoretical distribution very well. The applicable probability distribution of BOD can be used to explain more rigorously and scientifically the achievement or violation of target concentration in TMDL(Total Maximum Daily Load).

Rate of Convergence of Empirical Distributions and Quantiles in Linear Processes with Applications to Trimmed Mean

  • Lee, Sangyeol
    • Journal of the Korean Statistical Society
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    • 제28권4호
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    • pp.435-441
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    • 1999
  • A 'convergence in probability' rate of the empirical distributions and quantiles of linear processes is obtained. As an application of the limit theorems, a trimmed mean for the location of the linear process is considered. It is shown that the trimmed mean is asymptotically normal. A consistent estimator for the asymptotic variance of the trimmed mean is provided.

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Nonparametric Test for Used Better Than Aged in Convex Ordering Class(UBAC) of Life Distributions with Hypothesis Testing Applications

  • Abu-Youssef, S.E.
    • International Journal of Reliability and Applications
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    • 제10권2호
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    • pp.81-88
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    • 2009
  • A non-parametric procedure is presented for testing exponentially against used better than aged in convex ordering class (UBAC) of life distributions based on u-test. Convergence of the proposed statistic to the normal distribution is proved. Selected critical values are tabulated for sample sizes 5(5)40. The Pitman asymptotic relative efficiency of my proposed test to tests of other classes is studied. An example of 40 patients suffering from blood cancer disease demonstrates practical application of the proposed test.

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Determination of the Size Distribution of Magnetite Nanoparticles from Magnetic Measurements

  • Yoon, Sung-Hyun
    • Journal of Magnetics
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    • 제16권4호
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    • pp.368-373
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    • 2011
  • Particle size distributions in 10 nm magnetite ferrofluids are analyzed based on both dc and ac magnetic measurements. Modified log-normal distributions are used for fitting the experimental results, which allows for a proper account of the narrow distributions. The calculated average particle sizes are in good agreement with the TEM results. However the ac method gives a much narrower distribution width than that of the dc magnetization curve fit. The proposed measurements combined with the analysis methods are useful for the characterization of ferrofluids being considered for biomedical applications.

임상 자료 분석을 위한 NORMAL TEST VARIABLE(NTV)의 고찰 (Using a Normal Test Variable(NTV) for clinical research)

  • 이제영;우정수;최달우
    • 응용통계연구
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    • 제11권1호
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    • pp.129-139
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    • 1998
  • 임상자료의 정규성 검정에 있어서 NTV(Normal Test Variable)에 관한 몇가지 문제점을 여러 가지 특정분포 즉, 정규분포, 두 정규분포의 혼합분포, 균일분포, 지수분포 그리고 오른쪽을 치우친 베타분포에 관한 몬테칼로 모의실험 결과를 통하여 고찰하고 그 해결방안을 모색한다.

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MULTIVARIATE JOINT NORMAL LIKELIHOOD DISTANCE

  • Kim, Myung-Geun
    • Journal of applied mathematics & informatics
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    • 제27권5_6호
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    • pp.1429-1433
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    • 2009
  • The likelihood distance for the joint distribution of two multivariate normal distributions with common covariance matrix is explicitly derived. It is useful for identifying outliers which do not follow the joint multivariate normal distribution with common covariance matrix. The likelihood distance derived here is a good ground for the use of a generalized Wilks statistic in influence analysis of two multivariate normal data.

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An Attempt to Model Distributions of Machined Component Dimensions in Production

  • Cogun, Can;Kilinc, Biinyamin
    • Journal of Mechanical Science and Technology
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    • 제16권1호
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    • pp.60-74
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    • 2002
  • In this study, normal, log-normal, triangular, uniform. Weibull, Erlang and unit beta probability density functions are tried to represent the behaviour of frequency distributions of workpiece dimensions collected from various manufacturing firms. Among the distribution functions, the unit beta distribution function is found to be the best fit using the chi-square test of fit. An attempt is made for the adoption of the unit beta model to x-bar charts of quality control in manufacturing. In this direction, upper and lower control limits (UCL and LCL) of x-bar control charts of dimension measurements are estimated for the beta model, and the observed differences between the beta and normal model control limits are discussed for the measurement sets.

사삼맥문동탕이 Indomethacin으로 유발된 mouse의 대장 점막 손상에 미치는 영향 (The Effects of Sasammaickmoondong-tang against Colonic Mucosal Lesions)

  • 최준혁;임성우
    • 대한한의학회지
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    • 제23권4호
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    • pp.169-185
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    • 2002
  • Objectives: This study was carried out to investigate 1he effects of Sasammaickmoondong-tang(SME) on colonic mucosal lesions induced by indomethacin in mouse. Methods: The normal group is 1hat no inflammation elicitated mouse. Control group is that gastro-inflammation elicitated mouse. Sample group is that SME administered mouse after gastro-inflammation elicitation. Results: In the common morphology and histochemical change, control group was observed various injury-mucous surface cell, micro-villi, paneth cell, surface epithelial cell, goblet cell-by hemorrhagic erosion, while sample group was as same as normal group. In the immunohistochemical change, 1he distributions of COX-1, Bcl-2, and BrdU treated with SME noticeably increased than control group(P<0.05). The distributions of TUNEL, $NF-{\kappa}B$, COX-2, $IL-2R-\alpha$, NK-1.1, ICAM-1, and CD11b/18 treated with SME noticeably decreased than control group(P<0.05). And the distribution of SBA was as same as normal group. Conclusions: According to the above results, it is supposed that Sasammaickmoondong-tang is applicable to colonic mucosal lesions.

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Mouse의 위점막 염증에 대한 사삼맥문동탕의 면역반응 연구 (The Effects of Sasammaickmoondong-tang against Gastric Mucosal Lesions)

  • 김주성;임성우
    • 대한한의학회지
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    • 제24권2호
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    • pp.121-137
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    • 2003
  • Objectives: This study was carried out to investigate the effects of Sasammaickmoondong-tang (SME) on gastric mucosal lesions induced by indomethacin in mice. Methods: The normal group was no inflammation-induced mice. The control group was gastro-inflammation-induced mice. The sample group was mice administered SME after gastro-inflammation elicitation. Results: In the common morphology and histochemical change, the control group was observed with various injury-mucous surface cell, micro-villi, paneth cell, surface epithelial cell, goblet cell - by hemorrhagic erosion, while the sample group was as same as the normal group. In the immunohistochemical change, the distributions of COX-1, Bcl-2, and BrdU treated with SME were noticeably higher than in the control group (p<0.05). The distributions of TUNEL, NF-B, COX-2, IL-2R-, NK-1.1, ICAM-1, and CD11b/18 in those treated with SME were noticeably lower than in the control group (p<0.05). Finally, the distribution of SBA was the same as in the normal group. Conclusions: According to the above results, it is supposed that Sasammaickmoondong-tang is applicable to gastric mucosal lesions.

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