• Title/Summary/Keyword: Testing Hypotheses

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Bounds for the Full Level Probabilities with Restricted Weights and Their Applications

  • Park, Chul Gyu
    • Journal of the Korean Statistical Society
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    • v.25 no.4
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    • pp.489-497
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    • 1996
  • Lower bounds for the full level probabilities are derived under order restrictions in weights. Discussions are made on typical isotonic cones such as linear order, simple tree order, and unimodal order cones. We also discuss applications of these results for constructing conditional likelihood ratio tests for ordered hypotheses in a contingency table. A real data set on torus mandibularis will be analyzed for illustrating the testing procedure.

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중역정보시스템 개발방법의 평가

  • 변대호;정기호;신승용;서의호
    • Proceedings of the Korean Operations and Management Science Society Conference
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    • 1996.04a
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    • pp.675-678
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    • 1996
  • While a large number of firms have already developed and use an executive information system (EIS) effectively, some firms are reluctant to build one for lack of appropriate and well-organized guidance on how to achieve their own project. In this paper we suggest an EIS development methodology by testing five research hypotheses. As a result, we can conclude that prototyping should be applied to be combined with the SDLC. Moreover the preliminary stage accomplished the highest score in the eight-stage process.

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Test for an Outlier in Multivariate Regression with Linear Constraints

  • Kim, Myung-Geun
    • Communications for Statistical Applications and Methods
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    • v.9 no.2
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    • pp.473-478
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    • 2002
  • A test for a single outlier in multivariate regression with linear constraints on regression coefficients using a mean shift model is derived. It is shown that influential observations based on case-deletions in testing linear hypotheses are determined by two types of outliers that are mean shift outliers with or without linear constraints, An illustrative example is given.

Bayesian Test for the Intraclass Correlation Coefficient in the One-Way Random Effect Model

  • Kang, Sang-Gil;Lee, Hee-Choon
    • Journal of the Korean Data and Information Science Society
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    • v.15 no.3
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    • pp.645-654
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    • 2004
  • In this paper, we develop the Bayesian test procedure for the intraclass correlation coefficient in the unbalanced one-way random effect model based on the reference priors. That is, the objective is to compare two nested model such as the independent and intraclass models using the factional Bayes factor. Thus the model comparison problem in this case amounts to testing the hypotheses $H_1:\rho=0$ versus $H_2:{\rho}{\neq}0$. Some real data examples are provided.

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A nonparametric sequential test based on observations in groups (집단관측치에 의한 비모수적 축차검정에 관한 연구)

  • 박창순
    • The Korean Journal of Applied Statistics
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    • v.1 no.2
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    • pp.66-81
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    • 1987
  • A new nonparametric sequential testing procedure is proposed in the paper. Sequential observations are divided into equally sized groups and a nonparametric statistic, which is appropriate for testing the given hypotheses, is obtained from each group. Then Wald's sequential test is applied for the case where the log probability ratio statistic is replaced by the nonparametric statistic. The properties of such test are evaluated approximately by the Wiener process.

The Multiethnic Cohort Study of Diet and Cancer: Design and Early Findings

  • Kolonel, Laurence N.
    • Nutritional Sciences
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    • v.7 no.1
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    • pp.53-58
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    • 2004
  • The Multiethnic Cohort Study was designed to study prospectively the relationship of diet and other lifestyle factors to the risk of cancer. The cohort was established in 1993-1996 in Hawaii and California (primarily Los Angeles) and included a representative sample of more than 215,000 men and women primarily from five different ethnic groups: Japanese, whites, Native Hawaiians, Latinos, and African- Americans. Because of the emphasis on diet, great attention was paid to developing and pre-testing a self-administered quantitative food frequency questionnaire that would adequately assess food and nutrient intakes in these groups. An extensive food composition database was also created for the study. In addition, during data collection, a calibration study was conducted that makes possible adjustment for measurement error in nutrient intakes and valid comparison of intakes across the several ethnic groups. At the present time, blood and urine specimens are being collected from cohort participants and should yield a biorepository of more than 80,000 subjects. Baseline data indicate that the cohort is well representative of the general population of Hawaii and California, so that results can be generalized. These data also show a wide range in dietary intakes and in other lifestyle variables that should facilitate the testing of etiologic hypotheses.

On the Detection of Parameter Changes in Dynamical Systems for an Early Diagnosis of Cancer (암의 조기진단을 위한 계수변화 검출에 관한 연구)

  • Lee, Kwon-S.;Bae, Jong-Il.;Jeon, Gye-Rok
    • Proceedings of the KIEE Conference
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    • 1995.07b
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    • pp.748-750
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    • 1995
  • An early detection of cancer is very important for the complete cure of cancer. Therefore, it is considered a diagnosis of cancer via the detection of an abrupt change from the healthy state to the cancerous state. It includes the development of algorithm for the detection of parameter change for conditionally-linear stochastic systems for the cancer diagnosis. The statistical testing is proposed to implement a parameter change algorithm. The detection algorithm studied in this research is based on sequential hypotheses testing in a so-called local asymptotic framework. Here a simple numerical example is provided to highlight some of the concepts and to provide a basis for further investigation. Despite its simplicity this research may have practical application in clinical oncology.

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Moment inequalities of $NBU_{mgf}$ with testing hypotheses application

  • Mahmoud, M.A.W.;Gadallah, A.M.
    • International Journal of Reliability and Applications
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    • v.13 no.2
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    • pp.57-69
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    • 2012
  • Our goal in this paper is to establish inequalities for the moments of new better than used in the moment generating function class ($NBU_{mgf}$). Using these inequalities we propose a new test for exponentiality versus $NBU_{mgf}$ class. Pitman's asymptotic relative efficiency, power and critical values of this test are calculated to assess the performance of the test. We proposed also a new test for exponentiality versus $NBU_{mgf}$ in the right censored data. Sets of real data are used as an example to elucidate the use of the proposed test for practical problems.

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Count Five Statistics Using Trimmed Mean

  • Hong, Chong-Sun;Jun, Jae-Woon
    • Communications for Statistical Applications and Methods
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    • v.13 no.2
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    • pp.309-318
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    • 2006
  • There are many statistical methods of testing the equality of two population variances. Among them, the well-known F test is very sensitive to the normality assumption. Several other tests that do not assume normality have been proposed, but these tests usually need tables of critical values or software for hypotheses testing. McGrath and Yeh (2005) suggested a quick and compact Count Five test requiring only the calculation of the number of extreme points. Since the Count Five test uses only extreme values, this discards some information from the samples, often resulting in a degradation in power. In this paper, an alternative Count Five test using the trimmed mean is proposed and its properties are discussed for some distributions and normal mixtures.

A tutorial on generalizing the default Bayesian t-test via posterior sampling and encompassing priors

  • Faulkenberry, Thomas J.
    • Communications for Statistical Applications and Methods
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    • v.26 no.2
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    • pp.217-238
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    • 2019
  • With the advent of so-called "default" Bayesian hypothesis tests, scientists in applied fields have gained access to a powerful and principled method for testing hypotheses. However, such default tests usually come with a compromise, requiring the analyst to accept a one-size-fits-all approach to hypothesis testing. Further, such tests may not have the flexibility to test problems the scientist really cares about. In this tutorial, I demonstrate a flexible approach to generalizing one specific default test (the JZS t-test) (Rouder et al., Psychonomic Bulletin & Review, 16, 225-237, 2009) that is becoming increasingly popular in the social and behavioral sciences. The approach uses two results, the Savage-Dickey density ratio (Dickey and Lientz, 1980) and the technique of encompassing priors (Klugkist et al., Statistica Neerlandica, 59, 57-69, 2005) in combination with MCMC sampling via an easy-to-use probabilistic modeling package for R called Greta. Through a comprehensive mathematical description of the techniques as well as illustrative examples, the reader is presented with a general, flexible workflow that can be extended to solve problems relevant to his or her own work.