• 제목/요약/키워드: hypothesis tests

검색결과 349건 처리시간 0.024초

동조화 현상의 견인차 가설 검정과 분석 (Test and Analysis for Comovement-Locomotive Hypothesis)

  • 김태호
    • 응용통계연구
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    • 제24권2호
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    • pp.239-251
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    • 2011
  • 국가 간 경기 동조화 현장은 한 나라의 경기변동이 긴 시차를 두지 않고 관련국의 경기와 금융시장의 변동으로 직결되면서 동반 이동이 어떤 형태를 보이는지에 대한 통계적 분석의 필요성이 중대하고 있다. 본 연구에서는 동조화 현상과 파급효과에 대한 견인차 가설에 입각해 규모가 큰 경제가 작은 규모 국가의 변동을 유발하는지의 여부와 성향을 파악하고자 한 미 양국의 현재와 미래의 경기동향 및 주식시장 간 장기적 역학관계와 구조적 성향에 대해 통계적으로 검정해 보았다. 국내 주식시장에는 국내 경기동향이나 미국의 현 경기여건보다는 미국의 미래 경기전망이 유의한 영향을 미치는 것으로 나타났다.

범주형 자료에서 순서화된 대립가설 검정을 위한 정확검정의 개발 (Developing of Exact Tests for Order-Restrictions in Categorical Data)

  • 남주선;강승호
    • 응용통계연구
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    • 제26권4호
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    • pp.595-610
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    • 2013
  • 범주형 자료에서 순서화된 대립가설을 검정하는 경우는 의학 사회학 경영학 등 다양한 응용분야에서 발생한다. 이러한 검정 방법은 대부분 대표본이론에 근거하여 개발되었다. 하지만 표본크기가 작거나 표본크기가 매우 불균등한 경우 대표본이론에 근거한 검정방법의 제 1종 오류 확률은 목표로 하는 5%와 멀어지는 경우가 많이 발생한다. 본 논문에서는 범주형 자료에서 순서화된 대립가설을 검정하는 경우 표본크기가 작거나 표본크기가 매우 불균등한 경우에 사용될 수 있는 정확검정방법을 소개하고 이에 대한 검정력 및 정확 p-value를 제시할 것이다.

The Impact of Foreign Exchange Rates on International Travel: The Case of South Korea

  • Lee, Jung-Wan
    • 유통과학연구
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    • 제10권9호
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    • pp.5-11
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    • 2012
  • Purpose - The objective of the paper is to explain both the price sensitivity of international tourists to South Korea and the price sensitivity of Korean tourists to international travel. The study examines long-run equilibrium relationships and Granger causal relationships between foreign exchange rates and inbound and outbound tourism demand in South Korea. Research design/ data / methodology - The study employs monthly time series data from January 1990 to September 2010. The paper examines the long-run equilibrium relationship using the Johansen cointegration test approach after unit root tests. The short-run Granger causality was tested using the vector error correction model with the Wald test. Results - Hypothesis 1 testing whether there is a long-run equilibrium relationship between exchange rates, inbound and outbound tourism demand is supported. Hypothesis 2 testing whether exchange rates lead to a change in touristarrivals and expenditure is not supported. Hypothesis 3 testing whether exchange rates lead to a change in tourist departures and expenditure is supported. Conclusions - The findings of this study show that the impacts of tourism price competitiveness are changing quite significantly with regard to destination competitiveness. In other words, the elasticity of tourism price over tourism demand has been moderated.

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On the Cointegrating Relationship between Stock Prices and Earnings

  • Nam, Doo-Woo
    • 산학경영연구
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    • 제20권2호
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    • pp.1-13
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    • 2007
  • The purpose of this study is to investigate a simple present value model Involving earnings (i.e., the earnings discount model) that presumes a relationship between stock prices and earnings. The model suggests a simple linear equilibrium relationship between stock prices and earnings. The tests for cointegration render strong support for the cointegration hypothesis between stock prices (Pt) and earnings (Xt) even at the one-percent significance level. The tests are based on residuals from a cointegrating regression of Pt on Pt+l + Xt. This suggests that there is a stable long-nu equilibrium relationship between stock prices and earnings. The results of the tests lead to the acceptance of the present value model of stock prices involving earnings.

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Large tests of independence in incomplete two-way contingency tables using fractional imputation

  • Kang, Shin-Soo;Larsen, Michael D.
    • Journal of the Korean Data and Information Science Society
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    • 제26권4호
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    • pp.971-984
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    • 2015
  • Imputation procedures fill-in missing values, thereby enabling complete data analyses. Fully efficient fractional imputation (FEFI) and multiple imputation (MI) create multiple versions of the missing observations, thereby reflecting uncertainty about their true values. Methods have been described for hypothesis testing with multiple imputation. Fractional imputation assigns weights to the observed data to compensate for missing values. The focus of this article is the development of tests of independence using FEFI for partially classified two-way contingency tables. Wald and deviance tests of independence under FEFI are proposed. Simulations are used to compare type I error rates and Power. The partially observed marginal information is useful for estimating the joint distribution of cell probabilities, but it is not useful for testing association. FEFI compares favorably to other methods in simulations.

가속수명시험에 대한 적합도 검정에 관한 연구 (A Study on Goodness of Fit Test in Accelerated Life Tests)

  • 이우동;조건호
    • Journal of the Korean Data and Information Science Society
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    • 제7권1호
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    • pp.37-46
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    • 1996
  • 계단충격가속수명시험에서 얻은 자료를 토대로 통계적 추론을 위해 가정하는 수명분포에 대한 적합도 검정을 Kolmogorov-Smirnov, Cramer-von Mises, Anderson-Darling과 같은 비모수적 검정통계량들을 이용한 검정절차를 제안하고, 각 통계량들을 검정력 측면에서 비교하고자 한다.

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쿨백­라이블러 정보함수 이용한 단계 스트레스 가속수명모형의 지수성 검정 (Test of Exponentiality in Step Stress Accelerated Life test Model based on Kullback­Leibler Information Function)

  • 박병구;윤상철
    • 품질경영학회지
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    • 제31권4호
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    • pp.194-202
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    • 2003
  • In this paper, we propose goodness of fit test statistics for exponentiality in accelerated life tests data based on Kullback­Leibler information functions. This acceleration model is assumed to be a tampered random variable model. The procedure is applicable when the exponential parameter using the data from accelerated life tests is or is not specified under null hypothesis. And we compare the power of the proposed test statistics with Kolmogorov­Smirnov, Cramer von Mises and Anderson­Darling statistics in the small sample.

Statistically Proper Multiple Range Tests for a Within Subject Factor in a Repeated Measures Design

  • Park, Cheol-Yong;Park, Sang-Bum
    • Journal of the Korean Data and Information Science Society
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    • 제18권2호
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    • pp.525-534
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    • 2007
  • It is a common practice in many research areas that multiple range tests for a between subject factor such as Tukey are applied to a within subject factor in a repeated measures design. Tukey procedure, however, sometimes detects no pairs with different means even when the hypothesis of all equal level means is rejected. This study attempts to provide a rationale for the proposition that Tukey is inappropriate post hoc procedure for a within subject factor in which the observations are correlated. We introduce two multiple range tests, Bonferroni and Scheffe, for a within subject factor and show that Bonferroni is more appropriate than Scheffe for pairwise multiple comparisons. Subsequent simulation study indicates that Tukey has significantly less power than Bonferroni in detecting actual difference between means of some pairs when the observations of a within subject factor are highly correlated.

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k-표본 우산형 위치-척도 대립가설에 대한 순위검정법의 연구 (k-Sample Rank Tests for Umbrella Location-Scale Alternatives)

  • Hee Moon Park
    • 응용통계연구
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    • 제7권2호
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    • pp.159-171
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    • 1994
  • 본 논문에서는 $\kappa$-표본 문제에서 우산형 위치-척도 대립가설에 대한 순위검정법들을 연구하였다. 위치모수와 척도모수의 변동에 민감한 순위점수에 기초한 검정통계량들을 제안하였다. 우산형 대립가설의 정점이 알려진 경우를 다루었으며 귀무가설과 대립가설하에서의 점근성질도 아울러 조사되었다. 모수들간의 간격이 같지않는 우산형 위치-척도모형에서 Chen-Wolfe의 동위회귀 추정량을 이용한 순위통계량에 의존한 검정법이 효율적이었으며 또한 아주 안정적이었다.

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에지 검출을 위한 통계적 검정법 (Statistical Tests for Edg Detection)

  • 임동훈;성신희
    • 한국정보처리학회논문지
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    • 제7권3호
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    • pp.1021-1024
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    • 2000
  • In this paper we describe a nonparametric Wilcoxon test and a parametric Z test based on statistical hypothesis testing for the detection of edges. We use the threshold determined by specifying significance level $\alpha$, while Bovik, Huang and Munson[4] consider the range of possible values of test statistics for the threshold. From the experimental results of edge detection, the Z method performs sensitively to the noisy image, while the Wilcoxon method is robust over both noisy nd noise-free images. Comparison with our statistical tests and Sobel operator shows that our tests perform more effectively in both noisy and noise-free images.

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