• 제목/요약/키워드: test of normality

검색결과 286건 처리시간 0.036초

부문항이 분할된 고사에서 우량한 신뢰도 계수추경과 그 평가치 분포의 정규화 (On Estimating Good Reliability Coefficient when the Test is Split into Several Formats of Subtests and Standardizing the Raw Score, whose Distribution is Departed from Normality.)

  • 홍석강
    • 한국수학교육학회지시리즈A:수학교육
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    • 제41권1호
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    • pp.109-126
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    • 2002
  • In this thesis. we estimated the good reliability coefficient ${\beta}$$\sub$k/ that is unbiased, consistent and more efficient than Cronbach's ${\alpha}$$\sub$k/ in splitting of a test into several formats of subtests and several properties of ${\beta}$$\sub$k/ are also represented. The tables of coefficients of skewness and kurtosis are represented to test the significance of departures from normality. We got the cumulative normal plots of z'from the distribution which is departed from normality using the Bock's approximation procedure and we finally enumerated the transformed standardized scores z'and a new raw score X' which enable us to proceed further evaluation procedures depending on our assessment policy.

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가능도 함수를 기초로 한 다변량 정규성 검정 (A Test of the Multivariate Normality Based on Likelihood Functions)

  • 여인권
    • 응용통계연구
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    • 제15권2호
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    • pp.223-232
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    • 2002
  • 이 논문에서는 비선형 변환과 가능도 함수를 이용하여 다변량 자료의 정규성을 검정하는 방법에 대해 알아본다. 사용된 변환은 변환모수에 따라 여러 가지 형태를 가지는 변환족을 구성하는데 이 변환모수를 검정하여 자료의 정규성을 검정한다. 모수의 검정은 점수함수(score function)을 기초로 이루어지며 표본크기가 적은 경우에도 검정통계량의 분포를 유도하기 위한 모수적 붓스트랩 검정방법이 사용된다. 모의실험 결과 기존의 방법과 검정력을 비교하여 제안된 방법이 검정력이 높은 것으로 나타났다.

Logistic Model for Normality by Neural Networks

  • Lee, Jea-Young;Rhee, Seong-Won
    • Journal of the Korean Data and Information Science Society
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    • 제14권1호
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    • pp.119-129
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    • 2003
  • We propose a new logistic regression model of normality curves for normal(diseased) and abnormal(nondiseased) classifications by neural networks in data mining. The fitted logistic regression lines are estimated, interpreted and plotted by the neural network technique. A few goodness-of-fit test statistics for normality are discussed and the performances by the fitted logistic regression lines are conducted.

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탐진강 수질측정 지점 간 동질성 검정을 위한 비모수적 자료 분석 (A Non-parametric Analysis of the Tam-Jin River : Data Homogeneity between Monitoring Stations)

  • 김미아;이수웅;이재관;이정섭
    • 한국물환경학회지
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    • 제21권6호
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    • pp.651-658
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    • 2005
  • The Non-parametric Analysis is powerful in data test especially for the non- normality water quality data. The data at three monitoring stations of the Tam-Jin River were evaluated for their normality using Skewness, Q-Q plot and Shapiro-Willks tests. Various constituent of water quality data including temperature, pH, DO, SS, BOD, COD, TN and TP in the period of January 1994 to December 2004 were used as dataset. Shapiro-Willks normality test was carried out for a test 5% significance level. Most water quality data except DO at monitoring stations 1 and 2 showed that data does not normally distributed. It is indicating that non-parametric method must be used for a water quality data. Therefore, a homogeneity was conducted by Mann-Whitney U test (p<0.05). Two stations were paired in three pairs of such stations. Differences between stations 1, 2 and stations 1, 3 for pH, BOD, COD, TN and TP were meaningful, but Tam-Jin 2 and 3 stations did not meaningful. In addition, a narrow gap of the water quality ranges is not a difference. Categories in which all three pairs of stations (1 and 2, 2 and 3, 1 and 3) in the Tam-Jin River showed difference in water quality were analyzed on TN and TP. The results of in this research suggest a right analysis in the homogeneity test of water quality data and a reasonable management of pollutant sources.

Normal Probability Plots for Normality

  • Lee, Jea-Young;Rhee, Seong-Won
    • Communications for Statistical Applications and Methods
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    • 제6권3호
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    • pp.687-694
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    • 1999
  • The goodness of fit statistics of normality plots are obtained using the Receiver Operating Characteristic(ROC) method. This work is intended to compare with Shapiro-Wilk W statistic. Wel will use and discuss an accuracy of the test and the best cut-off value which minimizes the sum of the type I and II error probabilities.

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Testing Whether Failure Rate Changes its Trend Using Censored Data

  • Jeong, Hai-Sung;Na, Myung-Hwan;Kim, Jae-Joo
    • International Journal of Reliability and Applications
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    • 제1권2호
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    • pp.115-121
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    • 2000
  • The trend change in aging properties, such as failure rate and mean residual life, of a life distribution is important to engineers and reliability analysts. In this paper we develop a test statistic for testing whether or not the failure rate changes its trend using censored data. The asymptotic normality of the test statistics is established. We discuss the efficiency values of loss due to censoring.

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실험계획법에서 오차항의 가정 검토방안 (Assessment of Properties of Error Terms in Design of Experiment)

  • 최성운
    • 대한안전경영과학회:학술대회논문집
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    • 대한안전경영과학회 2012년 춘계학술대회
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    • pp.579-583
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    • 2012
  • The Design of Experiment (DOE) is a most practical technique when establishing an optimal condition for production technology in Six Sigma innovation project. This research proposes the assessment of properties of error terms, such as normality, equal variance, unbiasedness and independence. The properties of six nonparametric ranking techniques for checking normality assumption are discussed as well as run test which is used to identify the randomness, and to check unbiased assumption. Furthermore, Durbin-Watson (DW) statistics and ARIMA (p,d,q) process are discussed to identify the serial correlation.

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Omnibus tests for multivariate normality based on Mardia's skewness and kurtosis using normalizing transformation

  • Kim, Namhyun
    • Communications for Statistical Applications and Methods
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    • 제27권5호
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    • pp.501-510
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    • 2020
  • Mardia (Biometrika, 57, 519-530, 1970) defined measures of multivariate skewness and kurtosis. Based on these measures, omnibus test statistics of multivariate normality are proposed using normalizing transformations. The transformations we consider are normal approximation and a Wilson-Hilferty transformation. The normalizing transformation proposed by Enomoto et al. (Communications in Statistics-Simulation and Computation, 49, 684-698, 2019) for the Mardia's kurtosis is also considered. A comparison of power is conducted by a simulation study. As a result, sum of squares of the normal approximation to the Mardia's skewness and the Enomoto's normalizing transformation to the Mardia's kurtosis seems to have relatively good power over the alternatives that are considered.

정규성 그래프의 검정력 비교 (Power Analysis for Normality Plots)

  • 이제영;이성원
    • Journal of the Korean Data and Information Science Society
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    • 제10권2호
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    • pp.429-436
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    • 1999
  • 정규분포에 관한 검정에 있어서 P-P 플롯과 Q-Q 플롯에서 정규분포에서의 기대 직선의 잔차들을 이용한 두 가지 통계량을 제시하고, 이 통계량들의 경험적 분위수(empirical quantile)를 구하였다. 그리고 이들 통계량의 검정력을 Shapiro-Wilk의 W 통계량과의 비교를 통하여 분석하였다.

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A View on the Validity of Central Limit Theorem: An Empirical Study Using Random Samples from Uniform Distribution

  • Lee, Chanmi;Kim, Seungah;Jeong, Jaesik
    • Communications for Statistical Applications and Methods
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    • 제21권6호
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    • pp.539-559
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    • 2014
  • We derive the exact distribution of summation for random samples from uniform distribution and then compare the exact distribution with the approximated normal distribution obtained by the central limit theorem. To check the similarity between two distributions, we consider five existing normality tests based on the difference between the target normal distribution and empirical distribution: Anderson-Darling test, Kolmogorov-Smirnov test, Cramer-von Mises test, Shapiro-Wilk test and Shaprio-Francia test. For the purpose of comparison, those normality tests are applied to the simulated data. It can sometimes be difficult to derive an exact distribution. Thus, we try two different transformations to find out which transform is easier to get the exact distribution in terms of calculation complexity. We compare two transformations and comment on the advantages and disadvantages for each transformation.