• The Korean Journal of Applied Statistics
• /
• v.32 no.4
• /
• pp.631-642
• /
• 2019

Many methods have been developed to solve problems found in sample surveys involving a large number of item non-responses that cause inaccuracies in estimation. However, the non-response adjustment method used under the assumption of random non-response generates a bias in cases where the response rate is affected by the variable of interest. Chung and Shin (2017) and Min and Shin (2018) proposed a method to improve the accuracy of estimation by appropriately adjusting a bias generated when the response rate is a function of the variables of interest. In this study, we studied a case where the response rate function is linear and the error of the super population model follows normal distribution. We also examined the effect of the number of stratum population on bias adjustment. The performance of the proposed estimator was examined through simulation studies and confirmed through actual data analysis.

• The Journal of Korean Institute of Communications and Information Sciences
• /
• v.16 no.11
• /
• pp.1125-1131
• /
• 1991

In a generalized model with which we can represent multiplicative noise as well as purely additive noise, we consider detection of composite signals which contain both deterministic and stochastic signal components. To illustrate the performance of the locally optimum detectors, finite sample-size performance characteristics are obtained and compared with those of other detectors.

• Journal of Korean Society of Transportation
• /
• v.1 no.1
• /
• pp.82-103
• /
• 1983

본 연구는 1980년 Moses-Anas에 의해 제안된 $\ulcorner혼성로-짓모형\lrcorner$의 유효성을 서울 시의 출근통행실태 자료를 이용하여 검증하기 위한 것으로, $\ulcorner혼성로-짓모형\lrcorner$에 의한 추정 결과와 $\ulcorner전통적로-짓모형\lrcorner$에 의한 추정결과를 통계적 시점에서 상호 비교하였다. 이용된 자료는 1981년6월10일부터 6월16일까지 일주일간의 출근통행실태자료이며 조사표본수는 약 2000여 표본이었다. $\ulcorner혼성로-짓모형\lrcorner$에 의한 추정결과는 $\ulcorner전통적로-짓모형\lrcorner$ 에 의한 경 우보다 통계적으로 우월한 것으로 나타났으며, 특히 통행시간 및 통행비용에 대한 선택확률 의 탄력성은 $\ulcorner혼성모형\lrcorner$에 의해 추정된 결과가 더욱 합리적인 것으로 판명되었다.

• Proceedings of the Korea Contents Association Conference
• /
• 2010.05a
• /
• pp.604-606
• /
• 2010

이 연구는 한국인의 여가활동 제약과 생활만족의 관계를 규명하고자 한다. 이 연구는 성균대학교 동아시아학술원 서베이리서치센터에서 실시한 2007년 한국종합사회조사 데이터를 활용하였다. 한국종합사회조사에서는 다단계지역확률표본추출법을 이용하여 1,431명의 표본을 추출하였다. 이 연구에서는 SPSSWIN 17.0과 AMOS 5.0 프로그램을 적용하였다. 결론은 다음과 같다. 첫째, 여가활동 제약이 클수록 여가활동 동기는 약화된다. 둘째, 여가활동 제약은 여가활동 참가에 영향을 미치지 않는다. 셋째, 여가활동 제약은 생활만족에 영향을 미치지 않는다. 넷째, 여가활동 동기가 강화될수록 여가활동 참가는 증가한다. 다섯째, 여가활동 동기가 강화될수록 생활만족 또한 높아진다. 여섯째, 여가활동 참가가 증가할수록 생활만족 또한 높아진다.

• The Korean Journal of Applied Statistics
• /
• v.5 no.1
• /
• pp.9-17
• /
• 1992

In this paper we give a Bayesian approach to problems of estimation for the ratio in finite populations. Adopting the Ericson's superpopulatin approach in which the finite population of size N is viewed as arising form a random sample of N units from some superpopulation. We derive the exact posterior of the ratio under the noninformative prior on superpopulation parameters. Based on our results we compute an exact Bayesian confidence interval and compare this with the existing methods.

• The Korean Journal of Applied Statistics
• /
• v.15 no.1
• /
• pp.187-199
• /
• 2002

When the sample size is small, exact tests are often employed because the asymptotic distribution of the test statistic is in doubt. The advantage of exact tests is that it is guaranteed to bound the type I error probability to the nominal level. In this paper we review the methods of constructing exact tests, the algorithm and commercial software. We also examine the difference between exact p-values obtained from exact tests and true p-values obtained from the true underlying distribution.

• The Korean Journal of Applied Statistics
• /
• v.5 no.2
• /
• pp.271-282
• /
• 1992

A statistical method to investigate the relationship between the occurrence of Langerahans cells and neoplastic transformation of uterine cerivx. The best fitting submodel which satisfies the selection criterion similar in type to AIC is selected among the possible submodels based on Poisson probability models. A bootstrap method is used to approximate the sampling distribution of the selection criterion and the usual normal approximation is used to find the asymptotic distribution of the estimated rates.

• Journal of Korean Society of Transportation
• /
• v.15 no.1
• /
• pp.5-15
• /
• 1997

공간통계분석은 공간적으로 연계된 변수들간의 관계를 분석하는 통계분야이다. 일 반적으로 공간적으로 연계된 변수들간의 관계는 각 변수간의 공간적 분포정도에 따라서 영 향을 받는다. 전통적인 통계 분석의 방법은 동질의 자료발생과정에 의하여 확률적으로 축출 된 표본자료를 가정하고 있으나, 공간적인 자료는 이와 같은 동질의 자료발생과정의 가정을 부정한다. 교통류 및 교통사고 등과 같은 교통분야의 자료는 대부분 공간적인 상관관계에 의하여 축출된 이질적인 표본자료이며 따라서 공간상관관계를 동질적으로 가정한 전통적인 통계적 분석 방법은 오류를 범할 수 있다. 본 논문은 공간적인 관계를 고려한 공간자기상관 분석기법을 이용하여 고속도로상의 교통사고에 관하여 분석하였다. 분석의 결과에 의하면 4 개 고속도로 중 경인고속도로를 제외한 3개의 고속도로상의 교통사고건수는 통계적으로 현 저한 양의 공간적 상관관계가 있음을 알 수 있었다. 이에 따라 공간적 상관관계를 고려한 교통사고분석을 위하여 종속변수로 단위구간별 교통사고건수를 그리고 설명변수로서는 단위 구간별 교통량, I.C. 유무 및 화물차량비율을 이용하여 공간 자기회귀분석을 시도하였다. 분 석의 분석에서는 구간별 교통량과 화물차량의 비율이 호남/남해 고속도로의 경우에는 구간 별 교통량과 I.C. 유무가 통계적으로 유의한 것으로 분석되었다.

• Journal of Korea Water Resources Association
• /
• v.42 no.5
• /
• pp.365-374
• /
• 2009

Probability plotting positions are used for the graphical display of annual maximum rainfall or flood series and the estimation of exceedance probability of those values. In addition, plotting positions allow a visual examination of the fitness of probability distribution provided by frequency analysis for a given data. Therefore, the graphical approach using plotting position has been applied to many fields of hydrology and water resources planning. In this study, the plotting position formula for the Gumbel distribution is derived by using the order statistics and the probability weight moment of the Gumbel distribution for various sample sizes. And then, the parameters of plotting position formula for the Gumbel distribution are estimated by using genetic algorithm. The appropriate plotting position formulas for the Gumbel distribution are examined by the comparison of root mean square errors and biases between theoretical reduced Gumbel variates and those calculated from derived and existing plotting position formulas. As the results, Gringorten's plotting position formula has the smaller root mean square errors and biases than any other formulas.

• Journal of Technology Innovation
• /
• v.20 no.3
• /
• pp.57-91
• /
• 2012

This paper investigates determinants of litigation success in the two distinctive types of patent litigations, ex-parte and inter-parte cases, which are brought in the process where a filed application becomes a valid patent right. We regress winning rates of patent applicants on the characteristics of firms, trials, patent lawyer, and patent itself, using a probit model with sample selections. The paper finds that the relative suit rate of a firm, time to be sued, changes of patent agents by applicants, and multiple agents among explanatory variables affect ex-parte reexamination and in-parte post-grant patent trials differently in the point of average marginal effects. These variables lower the probability of applicant's victory in the ex-parte cases, while they raise the probability in the inter-parte trials. However, the experience that agents represent applicants is a winning rate-increasing factor both in inter-parte and ex-parte reexamination, unexpectedly. This result cannot be applied to the entire domain of the variable, since sample selection effects are reflected in the result. The number of claim increases the winning probability of the applicant in the both types of patent litigations. This study has some limitations because it ignores the information on the legal person to which a patent agent belongs, and confined agent's experience to patent filing. We leave it future studies to investigate the effects of lawsuit experience of patent agent, and those of characteristics of the law firm to which individual patent lawyer is affiliated.