• 정보학연구
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• 제3권1호
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• pp.37-44
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• 2000

다이아몬드 구매 예측 가격은 캐럿, 색깔, 투명도, 품질등급, 절단상태 및 캐럿 당 $ 가격의 6가지 요소에 의하여 영향을 받는다. 본 연구의 목적은 이러한 구매가격을 예측하기 위한 선형 회기모형을 구하고 이를 통계적 방법으로 검증하는데 있다. 최적화 모형은 부적격 검정결과 통계적으로 적합성을 갖는 $^y{\;}:{\;}10^2{\;}/{\;}(-1.5575{\;}+{\;}0.3099{\;}logx){\;}+{\;}{\varepsilon}$ 의 단순 회기모형으로 정규 분포성, 등분산성 및 대칭성의 특성을 갖는다.

• Communications for Statistical Applications and Methods
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• 제9권2호
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• pp.389-399
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• 2002

In order to examine whether the difference between two point estimates of population proportions is statistically significant, data analysts use two techniques. The first is to explore the overlap between two associated confidence intervals. Second method is to test the significance which is introduced at most statistical textbooks under the common assumptions of consistency, asymptotic normality, and asymptotic independence of the estimates. Under the null hypothesis which is two population proportions are equal, the pooled estimator of population proportion is preferred as a point estimator since two independent random samples are considered to be collected from one population. Hence as an alternative method, we could obtain another confidence interval of the difference of the population proportions with using the pooled estimate. We conclude that, among three methods, the overlapped method is under-estimated, and the difference of the population proportions method is over-estimated on the basis of the proposed method.

• Journal of the Korean Statistical Society
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• 제33권3호
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• pp.313-321
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• 2004

We consider the problem of testing cell probabilities in sparse multinomial data. Aerts et al. (2000) presented T=${{\Sigma}_{i=1}}^{k}{[{p_i}^{*}-E{(p_{i}}^{*})]^2$ as a test statistic with the local least square polynomial estimator ${{p}_{i}}^{*}$, and derived its asymptotic distribution. The local least square estimator may produce negative estimates for cell probabilities. The local maximum likelihood polynomial estimator ${{\hat{p}}_{i}}$, however, guarantees positive estimates for cell probabilities and has the same asymptotic performance as the local least square estimator (Baek and Park, 2003). When there are cell probabilities with relatively much different sizes, the same contribution of the difference between the estimator and the hypothetical probability at each cell in their test statistic would not be proper to measure the total goodness-of-fit. We consider a Pearson type of goodness-of-fit test statistic, $T_1={{\Sigma}_{i=1}}^{k}{[{p_i}^{*}-E{(p_{i}}^{*})]^2/p_{i}$ instead, and show it follows an asymptotic normal distribution. Also we investigate the asymptotic normality of $T_2={{\Sigma}_{i=1}}^{k}{[{p_i}^{*}-E{(p_{i}}^{*})]^2/p_{i}$ where the minimum expected cell frequency is very small.

• 대한정형도수물리치료학회지
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• 제24권2호
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• pp.17-27
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• 2018

Background: This study investigated the effects of pelvic floor stabilization exercise of pain, disfunction, psychosocial, electromyography (EMG) activity on the lower back pain with postpartum. Methods: The study included 20 postpartum women who were randomly assigned to a sling exercise group (SEG, n=10) or a general physical therapy group (GPTG, n=10). Outcomes were assessed using to lower back pain with postpartum the quadruple visual analogue scale (QVAS), the Korean version of the Oswestry disability index (KODI), the fear avoidance belief questionnaire (FABQ), the inventory of functional status after childbirth (IFSAC), the edinburgh postnatal depression scale-Korean (EPDS-K), and trunk muscle activity before and after a 4-week exercise intervention. Statistical analysis were performed using a mean, standard deviation, crosstab test, paired t-test, independent t-test. Kolmogorove-Smirnov test was used for test of normality. Results: Compared to the GPTG, the SEG showed significant improvement in the QVAS, KODI, FABQ, IFSAC, and EPDK-K scores (p<.05) after 4 weeks. Conclusion: Postpartum pelvic strengthening exercise proved to have a positive effect.

• Journal of the Korean Statistical Society
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• 제30권1호
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• pp.41-61
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• 2001

The minimum negative exponential disparity estimator(MNEDE), introduced by Lindsay(1994), is an excellenet competitor to the minimum Hellinger distance estimator(Beran 1977) as a robust and yet efficient alternative to the maximum likelihood estimator in parametric models. In this paper we define the negative exponential deviance test(NEDT) as an analog of the likelihood ratio test(LRT), and show that the NEDT is asymptotically equivalent to he LRT at the model and under a sequence of contiguous alternatives. We establish that the asymptotic strong breakdown point for a class of minimum disparity estimators, containing the MNEDE, is at least 1/2 in continuous models. This result leads us to anticipate robustness of the NEDT under data contamination, and we demonstrate it empirically. In fact, in the simulation settings considered here the empirical level of the NEDT show more stability than the Hellinger deviance test(Simpson 1989). The NEDT is illustrated through an example data set. We also define a goodness-of-fit statistic to assess adequacy of a specified parametric model, and establish its asymptotic normality under the null hypothesis.

• The Journal of Asian Finance, Economics and Business
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• 제8권2호
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• pp.667-673
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• 2021

This causal quantitative research aims to investigate the influence of factors that determine the performance of employees in Indonesian universities. The factors are crucial for organizations in the achievement of their goals. Based on theoretical studies, three independent variables, namely, training, personality, and work motivation were tested for their influence on employee performance, which was the dependent variable. Primary data were obtained from 94 respondents of a total population of 122 individuals at the Education Quality Assurance Institute (LPMP) in Banten Province, Indonesia. They were tested by the normality test using the Kolmogorov-Smirnov approach to ensure their normally distributed population and the linearity test to measure the significant linear relationship between the two variables. There are five hypotheses in this study. Each hypothesis tested by the F-test to determine the significant effect of all independent variables on the dependent variable, and t-test to analyze the effect. The results of this study answered all hypotheses of the research model. There is a positive direct effect of training and personality on work motivation. Both training and personality also affect positively employee performance. Another finding of this study is that employee performance is positively and directly affected by work motivation.

• The Journal of Asian Finance, Economics and Business
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• 제7권7호
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• pp.49-58
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• 2020

This paper examines the impact of mergers on the financial performance of the Jordanian banking sector. This paper applies the financial approaches in analysing the effects of mergers on Jordanian banks' performance for two the periods: four years pre-merger and four years' post-merger for the period from 2001 to 2009. The sample of the study solely contains the case of the merger of the Jordan Ahli Bank (AHLI bank) with Philadelphia Bank in 2005. Data are tested for normality using the Shapiro-Wilk Test and Kolmogorov Smirnov test. The financial ratios and a statistical technique as a Mann-Whitney U test were used to assess the significant differences in the financial performance of the selected banks pre- and post-merger by investigating the performance-related financial ratio groups that are expressed by leverage, liquidity, efficiency, and cash flow ratio. The results show that there is an insignificant improvement in the ratios of AHLI bank in the period after the merger, except for the superior result provided by this study indicating that the leverage ratios improved significantly. The reason for the insignificant improvement in financial ratios may be that the post-merger period corresponds to the period of the global financial crisis that began in 2007.

• 한국산업보건학회지
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• 제1권1호
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• pp.47-55
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• 1991

Exposure level of respirable coal dust of underground coal mines in Taebaek area was evaluated. Personal air samplers with 10-mm nylone cyclones were attached to the coal workers including drillers, coal cutters, their assistants, haulers, and separators. Log-normality of respirable dust exposure concentration were tested by Kolmogorov-Smirnov one-sample test. Differences of means of respirable dust exposure concentration between work sites were tested by one-way ANOVA test and multiple comparison(Scheffe) test. And differences of respirable dust exposure concentration of principal and assistant workers in drilling sites and in coal faces were tested by paired t-test. Relation of respirable dust exposure concentration for the principal workers and their assistants in drilling sites and in coal faces were tested by regression analysis. The results were as follows : 1. All of the respirable dust concentration were log-normally distributed. 2. There were not only significantly different means of exposure concentration between drillers and coal cutters but between coal cutters and haulers. 3. Means of exposure concentration of drillers and drilling assistants were not significantly different. And means of exposure concentration of coal cutters and coal cutting assistants were not different.

• 한국지반환경공학회 논문집
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• 제13권4호
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• pp.93-104
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• 2012

20세기 이후 지반의 불확실성을 이해하고 합리적인 해석방법을 개발하기 위한 노력이 경주되어 안전율 개념이 사용되어 왔으나 이러한 개념은 실제 적용되고 있는 인자들이 불확실성을 지님에도 그 대표값을 사용하기 때문에 지반구조물의 상대적인 신뢰성을 측정하는데 한계가 있다. 그러나 현재까지도 불확실성을 완전히 제거할 수 있는 방법은 없으며, 그나마 국내에서 수행되고 있는 지반조사 결과는 이러한 통계적 기법을 적용하는 것조차도 불가능할 정도로 충분치 못한 경우가 대부분이다. 또한 침하량이나 압밀속도 등 압밀 특성이 압밀이력에 따라 크게 차이가 남에도 불구하고 압밀상태에 대한 정확한 규명없이 설계하는 것은 많은 문제점을 나타내게 된다. 따라서 본 논문에서는 압밀인자 중 과압밀비를 중심으로 설계의 불확실성을 줄이기 위한 노력의 일환으로 남해안 중 광양과 부산지역에서 수행된 양질의 실내시험 결과를 바탕으로 압밀상태를 평가하고, 설계정수의 불확실성을 줄이기 위한 정규성 검증이나 이상치 제거 등의 통계처리를 통해 지역별로 깊이에 따른 과압밀비 등의 특성을 제안하였다.

• 간호행정학회지
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• 제8권2호
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• pp.323-334
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• 2002

Purpose: This study was designed to analyse economical efficiency of home care service by comparing a cost-effectiveness ratio(CER) between hospitalization and home care service. Method: The analytic framework of this study was constructed in 5 stages; perspective of the analysis, measurement of costs, measurement of effects, analysis of CER, and sensitivity analysis. The SAS program was utilized for the general characteristics of the subjects, descriptive statistics, homogeneous test, normality test and difference test. Result: The results were as follows; 1) CER was 35,248,256 of ADL, 7,996,026 of nursing satisfaction, 6,144,946,000 of QALY of patients in the hospital and 11,168,863 of ADL, 2,322,239 of nursing satisfaction, 3,674,556,000 of QALY of patients in the home care center. ICER was 438,067,932 of ADL, -190,044,176 of nursing satisfaction, 8,615,336,000 of QALY. 2) In the sensitivity analysis of sex, age and discount rate, the CER of patients in the home care center was lower than the CER of patients in the hospital. Conclusion: With these findings, it affirmed that home care service had an economical efficiency compared with hospitalization in cerebrovascular disease patients. Therefore, these results will be used to develop governmental policy or expansion of the home care service.