• 제목/요약/키워드: chi test

검색결과 4,952건 처리시간 0.037초

A Study on Cell Influences to Chi-square Statistic in Contingency Tables

  • Kim, Hong-Gie
    • Communications for Statistical Applications and Methods
    • /
    • 제5권1호
    • /
    • pp.35-42
    • /
    • 1998
  • Once a contingency table is constructed, the first interest will be the hypotheses of either homogeneity or independence depending on the sampling scheme. The most widely used test statistic in practice is the classical Pearson's $\chi^2$ statistic. When the null hypothesis is rejected, another natural interest becomes which cell contributed to the rejection of the null hypothesis more than others. For this purpose, so called cell $\chi^2$ components are investigated. In this paper, the influence function of a cell to the $\chi^2$ statistic is derived, which can be used for the same purpose. This function measures the effect of each cell to the $\chi$$^2$ statistic. A numerical example is given to demonstrate the role of the new function.

  • PDF

Empirical Analysis on Rao-Scott First Order Adjustment for Two Population Homogeneity test Based on Stratified Three-Stage Cluster Sampling with PPS

  • Heo, Sunyeong
    • 통합자연과학논문집
    • /
    • 제7권3호
    • /
    • pp.208-213
    • /
    • 2014
  • National-wide and/or large scale sample surveys generally use complex sample design. Traditional Pearson chi-square test is not appropriate for the categorical complex sample data. Rao-Scott suggested an adjustment method for Pearson chi-square test, which uses the average of eigenvalues of design matrix of cell probabilities. This study is to compare the efficiency of Rao-Scott first order adjusted test to Wald test for homogeneity between two populations using 2009 Gyeongnam regional education offices's customer satisfaction survey (2009 GREOCSS) data. The 2009 GREOCSS data were collected based on stratified three-stage cluster sampling with probability proportional to size. The empirical results show that the Rao-Scott adjusted test statistic using only the variances of cell probabilities is very close to the Wald test statistic, which uses the covariance matrix of cell probabilities, under the 2009 GREOCSS data based. However it is necessary to be cautious to use the Rao-Scott first order adjusted test statistic in the place of Wald test because its efficiency is decreasing as the relative variance of eigenvalues of the design matrix of cell probabilities is increasing, specially more when the number of degrees of freedom is small.

임의로 관측중단된 두 표본 자료에 대한 카이제곱 검정방법 (Two-sample chi-square test for randomly censored data)

  • 김주한;김정란
    • 응용통계연구
    • /
    • 제8권2호
    • /
    • pp.109-119
    • /
    • 1995
  • 두 모집단에서 임의로 관측중단도니 두 표본을 얻었을 때, 두 모집단의 분포가 같다는 가설을 검정하기 위한 카이제곱 검정방법이 제안되었다. 여기서 제안된 통계량은 대립가설이 두 모집단의 분포가 같지 않다는 양측가설일 때 쓰일 수 있다. 귀무가설이 사실일 때 제안된 통계량의 극한분포는 카이제곱 분포가 된다. 두 가지 형태의 카이제곱 검정통계량이 제안되었는데, 하나는 product-limit 추정치로부터 얻은 관측된 칸(cell) 확률의 차이들의 벡터의 이차형식으로 표현된 것이고, 다른 하나는 간단한 합의 모양으로 표현된 것이다. 두 형태의 검정통계량을 사용하여 암치료를 위한 화학요법 실험으로부터 얻은 자료를 분석하여 보았다.

  • PDF

대학도서관의 CD-ROM 네트워크 시스템 구축 현황 및 이용에 관한 연구 (A Study on the Construction and Use of CD-ROM Network Systems at University Libraries)

  • 김순원;정영미
    • 한국문헌정보학회지
    • /
    • 제33권3호
    • /
    • pp.145-167
    • /
    • 1999
  • 본 연구는 효율적인 CD-ROM 네트워크 시스템 설계 및 운영을 위해 고려해야 할 요인들을 도출시켜 시스템 설계자 및 운영자에게 도움이 되는 지침을 제공하는데 목적을 두고, 국내 72개 대학도서관의 CD-ROM 네트워크 시스템 현황과 문제점을 파악하였으며, 3개 대학 64명의 실제 이용자들을 대상으로 시스템 이용행태와 시스템에 대한 만족도를 분석하였다. 또한 이용자 만족도와 시스템 운영정책, 시스템 자원, 시스템 성능 요인간의 영향관계를 밝히기 위해 $\chi^2(Chi-Square)$검증과 F검증, 회귀분석을 실시하여 이용자 만족도에 영향을 미치는 요인들을 분석하였다.

  • PDF

골관절염 환자에게 적용한 타이치운동이 하지근력, 악력, 유연성, 통증, 우울 및 자기효능감에 미치는 효과 (Effect of Tai Chi Exercise Program on Muscle Strength, Grip Strength, Flexibility, Pain, Depression and Self-efficacy in Patients with Osteoarthritis)

  • 장경오
    • 근관절건강학회지
    • /
    • 제15권2호
    • /
    • pp.130-139
    • /
    • 2008
  • Purpose: The purpose of this study was to examine the effect of Tai Chi exercise on muscle strength, grip strength, flexibility, pain, depression and self-efficacy in patients with osteoarthritis. Method: With a quasi-experimental design, 46 persons with osteoarthritis were assigned into an experimental group (n=22) or a control group (n=24). Muscle strength, grip strength, flexibility, pain, depression and self-efficacy were measured both before and after the exercise. Data were analyzed with SPSS WIN using descriptive statistics, t-test, and ANCOVA. Results: The mean age of the subjects was 68 years in the experimental group and 64 years in the control group. After controlling for age and pre-test outcome variables, muscle strength scores (F=-14.8, p= .00), grip strength scores (Rt: F=8.40, p= .01), and self-efficacy (F=47.3, p= .00) improved more in the experimental group than the control group. Joint pain scores (F=15.0, p= .00) and depression scores (F=14.7, p= .00) decreased in the experimental group. Conclusion: Tai Chi exercise is likely to be an effective nursing intervention to improve muscle strength, grip strength, and self-efficacy and reduce pain and depression for patients with osteoarthritis.

  • PDF

Real-time Fault Detection Method for an AGPS/INS Integration System

  • Oh, Sang-Heon;Yoon, Young-Seok;Hwang, Dong-Hwan
    • 제어로봇시스템학회:학술대회논문집
    • /
    • 제어로봇시스템학회 2003년도 ICCAS
    • /
    • pp.974-977
    • /
    • 2003
  • The GPS/INS integration system navigation can provide improved navigation performance and has been widely used as a main navigation system for military and commercial vehicles. When two navigation systems are tightly coupled and the structure is complicated, a fault in either the GPS or the INS can lead to a disastrous failure of the whole integration system. This paper proposes a real-time fault detection method for an AGPS/INS integration system. The proposed fault detection method comprises a BIT and a fault detection algorithm based on chi-square test. It is implemented by real-time software modules to apply the AGPS/INS integration system and van test is carried out to evaluate its performance.

  • PDF

규칙적인 태극권의 참여가 유방암 수술환자의 산화-항산화계에 미치는 영향 (Tai Chi Exercise on MDA, SOD and Physical Fitness in Breast Cancer Patients)

  • 황인수;곽이섭
    • 생명과학회지
    • /
    • 제19권4호
    • /
    • pp.543-548
    • /
    • 2009
  • Treatment for breast cancer produces side effects that diminish functional capacity and quality of life (QOL) among survivors. Tai Chi is a moderate form of exercise that may improve functional capacity, physical activity and oxidative stress. The purpose of this study was to evaluate the effects of regular Tai Chi exercise on malondialdehyde (MDA), SOD and physical fitness (muscle strength, flexibility, flexion, extension, adduction, and abduction). Forty obese women were recruited from a public health center and divided into control (CON: n=20) and trained (EXP: n=20) groups. The Tai Chi exercise group participated in a 12-week (4 times/week) training program. Data were analyzed with T-test. MDA, SOD and physical fitness (muscle strength, flexibility, flexion, extension, adduction, and abduction) were evaluated before and after the Tai Chi program in both groups. There were significant improvements in shoulder flexibility, flexion, extension, abduction, and adduction. However, there was no improvement in muscle strength. There were also significant improvements in MDA and SOD. Based on these results, Tai Chi exercise has been shown to stimulate endogenous antioxidant enzymes and reduce oxidative damage markers. and also be effective in improving physical fitness and QOL. Further study is needed in this area.

슬골관절염 환자를 위한 타이치운동, 수중운동과 자조관리프로그램의 효과비교 (Comparison of Effects among Tai-Chi Exercise, Aquatic Exercise, and a Self-help Program for Patients with Knee Osteoarthritis)

  • 이혜영
    • 대한간호학회지
    • /
    • 제36권3호
    • /
    • pp.571-580
    • /
    • 2006
  • Purpose: This study was to compare the effects among Tai-Chi exercise, aquatic Exercise, and a self-help program for knee osteoarthritis patients on symptoms of arthritis, muscle strength, balance, and difficulty of performing activities. Method: There were 50 final subjects50. A non-equivalent pretest-posttest design was used. The collected data was analyzed using SPSS for Window. One-way ANOVA and Scheffe's multiple comparison test were used 8weeks after each program. Result: There were significant differences in joint pain(p=.000), stillness (p=.001), knee extensor peak torque(p=.006), knee flexor(p=.002), and difficult of performing activity (p=.000), but there was no significant difference in balance(p=.648). The Tai-Chi group was significantly different from the self-help group for knee extensor peak torque, knee flexor and stiffness on Scheffe's multiple comparison tests. In addition, the Tai Chi group or aquatic group were significantly different from the self-help group for difficulty of performing activities(p<0.05). Conclusion: There are significant differences in the effects of the nursing intervention among the three groups. The Tai Chi group and aquatic group were significantly different from the self-help group. However, it seems that Tai-chi exercise may be more suitable than aquatic exercise in osteoarthritis exercise programs. Further studies with a longitudinal study are necessary to confirm the longer exercise period.

타이치 운동프로그램이 골관절염 환자의 체력, 통증, 자기효능감에 미치는 효과 (Effects of Tai Chi Exercise Program on Physical Fitness, Pain, and Self-efficacy in Patients with Osteoarthritis)

  • 이윤정;임난영
    • 근관절건강학회지
    • /
    • 제16권1호
    • /
    • pp.26-35
    • /
    • 2009
  • Purpose: The purpose of this study was to investigate the effects of Tai Chi exercise program on physical fitness, pain, and self-efficacy in patients with osteoarthritis. Method: A preexperimental research design was applied to 22 subjects who dwelled at a welfare institution in C-city and agreed to participate in this study. The Tai Chi exercise was conducted with a duration of 60 minutes per session twice a week for 9 weeks. Outcome measures were physical fitness($VO_{2}max$, strength, flexibility, foot power, agility, balance), pain, and self-efficacy. Data were analyzed by descriptive statistics and paired t-test. Result: After participating in the Tai Chi exercise program, the subjects showed significant improvements in strength, agility, balance, pain and self-efficacy. But there were no significant differences in $VO_{2}max$, flexibility and foot power. Conclusion: The results showed that Tai Chi exercise would partially improve physical fitness and be effective for pain reduction and self efficacy as well. Further studies are needed to confirm the effects of Tai Chi exercise on physical fitness.

일개지역 고령자의 요실금의 유병률, 지식 및 배뇨특성 (Prevalence of Urinary Incontinence and Other Urologic Symptoms in a Community Residing Elderly People)

  • 김증임
    • 대한간호학회지
    • /
    • 제32권1호
    • /
    • pp.28-39
    • /
    • 2002
  • The purpose of this study was to measure the prevalence of urinary incontinence (UI), urologic symptoms, chronic health problems they have, and to explore whether the differences in incidence of UI ware by age, sex, voiding pattern, and chronic health problems. Method: 298 subject were selected, age range from 60 to 94 years residing in one city, in republic of Korea. Data was collected presence of UI, urologic symptoms, chronic health problems, knowledge, and the discomfort with incontinent. Collected data was analyzed with frequency, percentage, t-test, and $\chi$2-test. Result: The results of this study are as follows: 1. Mean age was 71.4 years. Prevalent rate of UI was 17.0%, woman showed more than man. 2. UI incidence was significant in age (t=7.84, p=.000), sex ($\chi$2 =9.47, p=.002), and voiding frequency ($\chi$2=18.34, p=.000). Also, UI incidence was significant relationship with chronic health problem of heart disease ($\chi$2 =10.65, p=0.001), hypertension ($\chi$2=4.04, p= 0.046) and respiratory problem ($\chi$2=9.67, p=0.002). 3. The UI was grouped into urgent incontinence (45%), stress incontinence (33%), and combined (22%). UI occurred during the daytime 48% and 17% at night. 4. Only 9.8 % of the UI seek advice and/or treatment for their symptoms, almost 90 % remained untreated due to lack of knowledge or improper information. 5. The discomforts due to their UI was no significant difference in their condition, the urgent use of the rest room, leaking urine, and nocturia. Conclusion: This study suggests that 1 year and 3 year follow-up study is needed to compare health status of UI. Also suggests intervention study for urologic discomfort of incontinent and behavioral education for the elderly are needed.