• Title/Summary/Keyword: Hypothesis Tests

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k-Sample Rank Procedures for Ordered Location-Scale Alternatives

  • Park, Hee-Moon
    • Journal of Korean Society for Quality Management
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    • v.22 no.2
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    • pp.166-176
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    • 1994
  • Some rank score tests are proposed for testing the equality of all sampling distribution functions against ordered location-scale alternatives in k-sample problem. Under the null hypothesis and a contiguous sequence of ordered location-scale alternatives, the asymptotic properties of the proposed test statistics are investigated. Also, the asymptotic local powers are compared with each others. The results show that the proposed tests based on the Hettmansperger-Norton type statistic are more powerful than others for the general ordered location-scale alternatives. However, the Shiraishi's tests based on the sum of two Bartholomew's rank analogue statistics are robust.

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Some versatile tests based on percentile tests

  • Park, Hyo-Il;Kim, Ju-Sung
    • Journal of the Korean Data and Information Science Society
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    • v.21 no.2
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    • pp.291-296
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    • 2010
  • In this paper, we consider a versatile test based on percentile tests. The versatile test may be useful when the underlying distributions are unknown or quite different types. We consider two kinds of combining functions for the percentile statistics, the quadratic and summing forms and obtain the limiting distributions under the null hypothesis. Then we illustrate our procedure with an example. Finally we discuss some interesting features of the test as concluding remarks.

A Simultaneous Test Procedure

  • Hong, Seungman;Cho, Joong-Jae;Park, Hyo-Il
    • Communications for Statistical Applications and Methods
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    • v.21 no.1
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    • pp.11-22
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    • 2014
  • In this study, we propose a simultaneous test procedure based on the individual - values for each sub-null hypothesis with several well-known combining functions. We then compare the efficiency of our procedure with existing tests by obtaining empirical powers through a simulation study. Finally, we discuss some interesting features related to simultaneous test and point out a misconduct for the simulation study published in the previous work.

A Simple Nonparametric Test of Complete Independence

  • Park, Cheol-Yong
    • Communications for Statistical Applications and Methods
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    • v.5 no.2
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    • pp.411-416
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    • 1998
  • A simple nonparametric test of complete or total independence is suggested for continuous multivariate distributions. This procedure first discretizes the original variables based on their order statistics, and then tests the hypothesis of complete independence for the resulting contingency table. Under the hypothesis of independence, the chi-squared test statistic has an asymptotic chi-squared distribution. We present a simulation study to illustrate the accuracy in finite samples of the limiting distribution of the test statistic. We compare our method to another nonparametric test of complete independence via a simulation study. Finally, we apply our method to the residuals from a real data set.

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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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    • v.10 no.2
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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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A Study on the Job Satisfaction of KNR (철도직무만족도에 관한 연구)

  • 김정평
    • Proceedings of the KSR Conference
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    • 1999.11a
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    • pp.81-90
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    • 1999
  • This study focuses on what factors influence the job satisfaction of KNR. For solving this research question, three important factors affected job satisfaction are selected through literature review : harmonics communication, fairness of personnel management, satisfaction of human relations. This study tests that the cognitive degrees of above factors are defending on different personal characteristics, and also searches the relationship between job satisfaction and the three factors. This study makes the hypothesis based on a conceptual model elicited from the outline of the previous study. To verify the hypothesis, using SPSS WIN 7.5 package is practiced.

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Influences of Cognitive Conflict and Non-cognitive Variables Induced by Discrepant Event and Alternative Hypothesis on Conceptual Change (변칙사례 및 대안가설에 의해 유발된 인지갈등과 비인지적 변인이 개념변화에 미치는 영향)

  • Kang, Hun-Sik;Kwack, Jin-Ha;Kim, You-Jung;Noh, Tae-Hee
    • Journal of the Korean Chemical Society
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    • v.51 no.1
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    • pp.56-64
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    • 2007
  • This study examined the influences of cognitive conflict and anxiety induced by a discrepant event and an alternative hypothesis, attention, and effort on conceptual change. Two hundred three students having misconceptions about density were selected from 462 seventh graders based on the results of a preconception test. Tests of cognitive responses and anxiety to a discrepant event were administered before and after presenting an alternative hypothesis. Computer-assisted instruction (CAI) was then provided to students as a conceptual change intervention. Tests assessing attention and effort allocated to the CAI, and conceptual understanding were administered as posttests. Cognitive conflict induced by a discrepant event was found to increase after presenting an alternative hypothesis. Pre-cognitive conflict induced by only a discrepant event exerted a direct effect on post-cognitive conflict induced by a discrepant event and an alternative hypothesis. Post-cognitive conflict had a direct effect on conceptual change. Pre-anxiety decreased after presenting an alternative hypothesis. Pre-anxiety influenced post-anxiety, and this influenced on conceptual change via effort negatively. Attention had a direct effect as well as an indirect effect on conceptual change via effort. These results suggest that the strategy presenting both a discrepant event and an alternative hypothesis to students in concept learning could facilitate conceptual change by inducing more cognitive conflict or active participation of students through the decrease of anxiety than that presenting a discrepant event only.

Simple Recursive Approach for Detecting Spatial Clusters

  • Kim Jeongjin;Chung Younshik;Ma Sungjoon;Yang Tae Young
    • Communications for Statistical Applications and Methods
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    • v.12 no.1
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    • pp.207-216
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    • 2005
  • A binary segmentation procedure is a simple recursive approach to detect clusters and provide inferences for the study space when the shape of the clusters and the number of clusters are unknown. The procedure involves a sequence of nested hypothesis tests of a single cluster versus a pair of distinct clusters. The size and the shape of the clusters evolve as the procedure proceeds. The procedure allows for various growth clusters and for arbitrary baseline densities which govern the form of the hypothesis tests. A real tree data is used to highlight the procedure.

Nonparametric Tests for Detecting Greater Residual Life Times

  • Lim, Jae-Hak;Ibrahim A. Ahmad;Park, Dong-Ho
    • Proceedings of the Korean Reliability Society Conference
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    • 2004.07a
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    • pp.167-175
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    • 2004
  • A nonparametric procedure is proposed to test the exponentiality against the hypothesis that one life distribution has a greater residual life times than the other life distribution. Such a hypothesis turns out to be equivalent to the one that one failure rate is greater than the other and so the proposed test works as a competitor to more IFR tests by Kochar (1979, 1981) and Cheng (1985). Our test statistic utilizes the U-statistics theory and a large sample nonpara metric test is established. The power of the proposed test is discussed by calculating the Pitman asymptotic relative efficiencies against several alter native hypotheses. A numerical example is presented to exemplify the proposed test.

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Comparison of Structural Change Tests in Linear Regression Models

  • Kim, Jae-Hee
    • The Korean Journal of Applied Statistics
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    • v.24 no.6
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    • pp.1197-1211
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    • 2011
  • The actual power performance of historical structural change tests are compared under various alternatives. The tests of interest are F, CUSUM, MOSUM, Moving Estimates and empirical distribution function tests with both recursive and ordinary least-squares residuals. Our comparison of the structural tests involves limiting distributions under the hypothesis, the ability to detect the alternative hypotheses under one or double structural change, and smooth change in parameters. Even though no version is uniformly superior to the other, the knowledge about the properties of those tests and connections between these tests can be used in practical structural change tests and in further research on other change tests.