• 제목/요약/키워드: Hypothesis testing

검색결과 772건 처리시간 0.025초

무선재추출법에 기초한 사건관련전위 자료분석에 대한 탐색적 고찰 (An Exploratory Observation of Analyzing Event-Related Potential Data on the Basis of Random-Resampling Method)

  • 현주석
    • 감성과학
    • /
    • 제20권2호
    • /
    • pp.149-160
    • /
    • 2017
  • 가설검증 과정에서 자료 분석 결과 산출된 통계치에 대한 해석은 몇 가지 통계학적 이론을 토대로 분석 결과 산출된 관련 통계치의 이론적 확률 분포에 의해 좌우된다. 예를 들어 실험 조건 간 측정치의 평균 차이에 대한 통계적 유의미성은 대개 전집 특성에 대한 몇 가지 이론적 가정에 기초해 구성된 해당 평균 차이값의 확률 분포(예: Student's t)에 기초해 결정된다. 본 연구는 이러한 이론적 통계치의 분포가 아닌 실측정 자료의 무선 재구성을 통해 얻어진 경험적 통계치의 분포에 기초해 가설 검증을 시도하는 무선재추출법의 기본 논리와 장점을 살펴보고 사건관련전위 분석 상황에서의 응용 가능성을 모색하였다. 더 나아가 무선 추출 원리에 기초한 무선치환법이 적용된 구체적 사례를 소개하고 ERP 자료 분석에 있어서 경험적 통계 분석 적용에 앞서 유의할 점을 살펴봄으로써 뇌파 연구자들의 무선재추출법에 대한 정확한 이해를 도모하였다.

요리 미술 활동이 치매 노인의 인지기능 및 우울에 미치는 효과 (The Effect of Cooking and Art Activities on Cognitive Function and Depression of Dementia Patients)

  • 정춘임;김이순;이해웅;김경철
    • 대한한의진단학회지
    • /
    • 제15권1호
    • /
    • pp.67-76
    • /
    • 2011
  • Objectives: The purpose of this study was to examine the effect of cooking and art activities on cognitive function and depression of dementia patients. Methods: The study was carried out on 34 dementia patients (experimental group: 17 persons, control group: 17 persons) at 65 years old or more who correspond to a total MMSE-M, MMSE-K point between 15 and 23 points instituted in a specialized nursing facility in Busan from November 30, 2007 to February 20, 2008. The study used a nonequivalent pretest-posttest design. In previous survey, the study measured points of general characteristics, cognitive function and melancholy. To the experimental group, cooking art activities were carried out for 90 minutes every time and once every week for 12 weeks. Results: Analysis on data was performed using SPSS/WIN 14.0. In addition $x^2$-test, Fisher's exact test and t-test were used for testing of homogeneity and ANOVA was performed for testing of hypothesis. The results of this study are as follows. 1. Hypothesis 1 that 'The experimental group with cooking art activities will show a higher point of cognitive function than the control group without cooking art activities' was supported (F=65.497, p<0.001). 2. Hypothesis 2 that 'The experimental group with cooking art activities will show a lower point of melancholy than the control group without cooking art activities' was supported. (F=27.463, p<0.001) Conclusions: From the above results, cooking art activities showed a significant difference in the increase in cognitive function and reduction in melancholy of dementia patients.

패널분석을 이용한 6대 권역별 대기오염물질에 대한 환경규제와 경제성장 간의 상호관계분석: EKC(환경쿠즈네츠곡선)가설을 중심으로 (The correlation among the GHG (Greenhouse Gas) emission, energy consumption and economic growth for the 6 specific regions in Korea by using Panel approaches:By Testing of the EKC(Environmental Kuznets Curve))

  • 박추환
    • 환경정책연구
    • /
    • 제12권2호
    • /
    • pp.59-86
    • /
    • 2013
  • 1988년부터 2008년까지의 자료를 바탕으로 우리나라 6개 권역을 대상으로 권역별 소득, 환경규제, 오염유발원이 각 권역별 대기오염 물질(황산화물, 질소산화물, 총먼지, 일산화탄소)에 미치는 영향을 지역적 관점에서 살펴보았다. 즉, 환경 쿠즈네츠 곡선(EKC)가설 검증차원에서 공해배출과 경제성장 간의 관계를 패널회귀분석을 통해 분석하였다. 분석 결과, 산업시설에 영향을 미치고 있는 황산화물(SOx)의 경우 대부분의 권역에서 EKC가설이 성립하는 것으로 나타났지만, 질소산화물(NOx)과 총먼지(TSP)의 경우 6개 권역 중 대경권에서만 EKC가설이 성립하는 것으로 나타났 으며, 일산화탄소(CO)의 경우에도 EKC가설을 충족시키는 권역은 중부권, 호남권, 동남권에 한정되어 있었다. 또한 각 권역별 대기오염 단속규제가 대기오염과 정(+)의 관계를 보임에 따라 환경규제효과가 나타난다고 보기 어려우며, 각 권역별 연료소비와 석유화학제품의 특화 또한 권역별 대기오염을 증가시키는 주요 요인으로 작용하고 있다.

  • PDF

한국 여성사서의 직력유형(職歷類型)에 영향을 미치는 요인에 관한 연구 (A Study on the Factors Affecting Career Patterns of Korean Female Librarians)

  • 최은주
    • 한국문헌정보학회지
    • /
    • 제21권
    • /
    • pp.103-140
    • /
    • 1991
  • Knowledge about career patterns of women In any profession and about factors which influence these career patterns becomes increasingly necessary because of the influx of ever-increasing numbers of women into the labor force, and the need for the development and utilization of the creative productivity of women. This study alms to investigate Korean female librarians' overall career patterns and verify relevant factors which might affect to their career patterns. As an instrument, self-reported questionnaires were sent to 1,251 full-time Korean female librarians throughout the country with regular librarian's certificate, currently engaging in public, college or university, and special libraries. Based on the data gathered, the interrelationship between their career pattern inclination and its influential factors were examined through hypothesis testing. Major findings of the survey are outlined in the following: 1). Female librarians' career patterns were classified into five categories with the group represented as Categories-2 (single; wishes to continue working after marriage; places an emphasis on the sense of occupational accomplishment and social prestige) accounted for the highest proportion$(33.4\%)$. 2). The result of the hypothesis testing revealed that there is no significant relationship statistically between social factors(parents' socio-economic status, etc.) and female librarians' career patterns. So the hypothesis concerning social factors were rejected. 3). In psychological factors(job satisfaction ; self-concept sex role attitude ; role conflict ; and achievement motivation), all except for self-concept were shown to be relevant with female librarians' stable career pattern. So the hypotheses concerning psychological factors were supported. 4). According to the result of multiple discriminant analysis conducted between the above four statistically significant psychological factors and career patterns, the most influential factor for female librarians' career patterns was job satisfaction and sex role. In conclusion, the following recommendations were made: For overall enhancement of Korean female librarianship, earlier career guidance and concrete sex role education for young women is urgent which enable them to establish correct viewpoint for their occupational career female librarians themselves' constant endeavor In maintaining positive attitude toward their job is required.

  • PDF

Intrinsic Priors for Testing Two Lognormal Means with the Fractional Bayes Factor

  • 문경애
    • 한국데이터정보과학회:학술대회논문집
    • /
    • 한국데이터정보과학회 2003년도 추계학술대회
    • /
    • pp.39-47
    • /
    • 2003
  • The Bayes factors with improper noninformative priors are defined only up to arbitrary constants. So, it is known that Bayes factors are not well defined due to this arbitrariness in Bayesian hypothesis testing and model selections. The intrinsic Bayes factor by Berger and Pericchi (1996) and the fractional Bayes factor by O'Hagan (1995) have been used to overcome this problems. This paper suggests intrinsic priors for testing the equality of two lognormal means, whose Bayes factors are asymptotically equivalent to the corresponding fractional Bayes factors. Using proposed intrinsic priors, we demonstrate our results with a simulated dataset.

  • PDF

퍼지 사전 모수에 관한 베이지안 가설검정 (Hypotheses testing of Bayes' theorem for fuzzy prior parameters)

  • 강만기;최규탁
    • 한국지능시스템학회:학술대회논문집
    • /
    • 한국퍼지및지능시스템학회 2005년도 추계학술대회 학술발표 논문집 제15권 제2호
    • /
    • pp.205-208
    • /
    • 2005
  • We have fuzzy hypotheses testing from Bayesian statistics with ideas from fuzzy sets theory to generalize Bayesian methods both for samples of fuzzy data and for prior distributions with non-precise parameters. Appling the principle of agreement index, the posterior odds ratio in the favor of hypotheses $H_0$ is equal to product of the fuzzy odds ratio and the fuzzy likelihood ratio. If the Posterior odds ratio exceeds the grade judgement, we accept the hypothesis $H_0$ for the degree.

  • PDF

The Sequential Testing of Multiple Outliers in Linear Regression

  • Park, Jinpyo;Park, Heechang
    • Communications for Statistical Applications and Methods
    • /
    • 제8권2호
    • /
    • pp.337-346
    • /
    • 2001
  • In this paper we consider the problem of identifying and testing the outliers in linear regression. first we consider the problem for testing the null hypothesis of no outliers. The test based on the ratio of two scale estimates is proposed. We show the asymptotic distribution of the test statistic by Monte Carlo simulation and investigate its properties. Next we consider the problem of identifying the outliers. A forward sequential procedure based on the suggested test is proposed and shown to perform fairly well. The forward sequential procedure is unaffected by masking and swamping effects because the test statistic is based on robust estimate.

  • PDF

Testing Whether a Survival Distribution is Better Mean Residual Life at Age $t_0$

  • Alwasel Ibrahim A.;El-Bassiouny Ahmed H.
    • International Journal of Reliability and Applications
    • /
    • 제7권1호
    • /
    • pp.1-11
    • /
    • 2006
  • The better mean residual life at $t_0\;(BMRL-t_0)$ class of life distribution is introduced by Kulasekara and Park (1987). They proved that the $BMRL-t_0$ class contains the DMRL class, but it is a proper subclass of the NBUE class. In this paper we develop a new family of tests for testing exponentiality against the $BMRL-t_0\;(WMRL-t_0)$ alternatives based on the goodness of fit approach. It is shown that the suggested test is better than the one introduced by Kulasekara and Park (1987) in the sense of Pitman asymptotic efficiency values.

  • PDF

The Scale Ratio Testing of Multiple Outliers in Linear Regression

  • Park, Jin-Pyo
    • Journal of the Korean Data and Information Science Society
    • /
    • 제14권3호
    • /
    • pp.673-685
    • /
    • 2003
  • In this paper we consider the problem of identifying and testing outliers in linear regression. First we consider the problem for testing the null hypothesis of no outliers. A test based on the ratio of two residual scale estimates is proposed. We show the asymptotic distribution of the test statistics by Monte Carlo simulation and investigate its properties. Next we consider the problem of identifying the outliers. A forward sequential procedure using the suggested test is proposed and shown to perform fairly well. Unlike other forward procedures, the present one is unaffected by masking and swamping effects because the test statistic is based on robust scale estimate.

  • PDF

Intrinsic Priors for Testing Two Lognormal Populations with the Fractional Bayes Factor

  • Moon, Gyoung-Ae
    • Journal of the Korean Data and Information Science Society
    • /
    • 제14권3호
    • /
    • pp.661-671
    • /
    • 2003
  • The Bayes factors with improper noninformative priors are defined only up to arbitrary constants. So, it is known that Bayes factors are not well defined due to this arbitrariness in Bayesian hypothesis testing and model selections. The intrinsic Bayes factor by Berger and Pericchi (1996) and the fractional Bayes factor by O'Hagan (1995) have been used to overcome this problems. This paper suggests intrinsic priors for testing the equality of two lognormal means, whose Bayes factors are asymptotically equivalent to the corresponding fractional Bayes factors. Using proposed intrinsic priors, we demonstrate our results with real example and a simulated dataset.

  • PDF