• Proceedings of the Korean Statistical Society Conference
• /
• 2005.05a
• /
• pp.203-207
• /
• 2005

A loss system where two types of customers arrive in accordance with two independent Poisson processes is considered. An efficient recursive formula is developed for calculating the loss probability when the number of servers is large. Some practical examples regarding the performance evaluation of telecommunications networks are discussed.

• Proceedings of the KSR Conference
• /
• 2011.10a
• /
• pp.2182-2191
• /
• 2011

Postmortem evaluation through the dictionary and the lack of points for the wrong strategy to respond to the avoid the prediction is important. However, the prevailing system of ex post facto assessment of postmortem simply does not have statistical figures to be provided only for the conditions. Thus, in this study, rail business is mainly evaluation procedures and evaluation of the verification system of ex post facto evaluation as to the issue, do not improve.

• Communications of the Korean Mathematical Society
• /
• v.36 no.4
• /
• pp.835-840
• /
• 2021

In this paper, we compute the rational evaluation subgroup of the Hopf fibration S²ⁿ⁺¹ ↪ ℂP(n). We show that, for the Sullivan model 𝜙 : A → B, where A and B are the minimal Sullivan models of ℂP(n) and S²ⁿ⁺¹ respectively, the evaluation subgroup G_n(A, B; 𝜙) and the relative evaluation subgroup G^rel_n (A, B; 𝜙) of 𝜙 are generated by single elements.

• Journal of the Korean Professional Engineers Association
• /
• v.29 no.2
• /
• pp.71-79
• /
• 1996

This paper evaluates the clustering performance of a neural network and a statistical method. Algorithms which are used in this paper are the GLVQ(Generalized Loaming vector Quantization) for a neural method and the k -means algorithm for a statistical clustering method. For comparison of two methods, we calculate the Rand's c statistics. As a result, the mean of c value obtained with the GLVQ is higher than that obtained with the k -means algorithm, while standard deviation of c value is lower. Experimental data sets were the Fisher's IRIS data and patterns extracted from handwritten numerals.

• Korean Journal of Pharmacognosy
• /
• v.3 no.2
• /
• pp.57-64
• /
• 1972

For the purpose of scientific evaluation of oriental medicine, statistical analyses of oriental medicine formularies have been attempted. Four hundred and sixty seven prescriptions in 'Bang-Yak-Hap-Pyon', the most popular formulary of oriental medicine in Korea, were analysed to obtain statistical characteristics on the prescription frequency and origin distribution of two hundred and ninety three herb drugs.

• Asia pacific journal of information systems
• /
• v.7 no.2
• /
• pp.77-102
• /
• 1997

The use of statistical methods in the MIS research is increasing. However, there has been a meager attempt to critically evaluate the use statistical methods in MIS research papers. The review of 33G papers published in MIS Quarterly from Volume 1 to 14 resulted in three findings; (1) the portion of empirical research has been gradually increasing compared with non-empirical research, (2) univariate parametric statistical methods are most popular among MIS researchers, (3) researchers do not comply with the writing code of scientific research. This paper disscusses what errors MIS researchers might commit in using statistical research methods and how to prevent those errors in each of three stages of research, research design phase, statistical inference phase, and interpretation phase.

• Journal of the Korean Society of Tobacco Science
• /
• v.20 no.1
• /
• pp.108-114
• /
• 1998

This study was conducted to evaluate the techniques or analyzing tobacco smoke by statistical treatment method for the analytical data through Asia Collaborative Study V. In addition to five smoke components analysis, consisting of TPM, water, nicotine, NFDPM, and puff count of four cigarettes samples, statistical parameters such as mean, standard deviation, box-and-whisker plots, h plots, k plots, regression coefficients, reproducibility (R), and repeatability (r) were also calculated. Analysis of water content of cigarette smoke was the most difficult task, whereas puff count analysis was the easiest as well recognized by all laboratories. Analysis of nicotine and puff count accounted for both the lowest and the highest variation among four parameters. The water coefficients indicated more randomness or variation in the slops. The NFDPM data exhibited both types of deviations from linearity. Water content of sample D indicated the highest difference between two single results and between two interlaboratory test results. As a whole, KGTRI ranked higher in the analytical techniques for statistical evaluation of results when compared with the practices of 28 other laboratories.

• International Journal of Naval Architecture and Ocean Engineering
• /
• v.3 no.1
• /
• pp.80-85
• /
• 2011

For the assessment of statistical characteristics of wave loads in the real sea state, the probability distribution of wave loads are computed based on the sufficient duration of computations in irregular waves. First of all, the estimation of wave impact loads is well modified applying the displacement potential formulation, which was proposed by one of authors, for solving Wagner's flow model. Consequently, the present computation method is also modified. Prior to the computation in irregular waves, preliminary computation to determine the adequate number of realization of irregular waves is examined. The effect of hull girder vibration on the statistical characteristics is examined by means of the computation with/without hull girder vibration. It is found that hull girder vibration has a certain effect on the probability of occurrence of wave loads. Furthermore, computations taking account of the effect of operation, that is the effects of ship speed and course change, is conducted for the rational evaluation of the effects of hull girder vibration. It is clarified that the effect of operation on the statistical characteristics of wave loads is significant. It is verified that the evaluation without the effect of operation may overestimate the effect of hull girder vibration.

• Journal of Environmental Science International
• /
• v.30 no.11
• /
• pp.937-944
• /
• 2021

In this study, water resource topics, infrastructure, water supply, users, and economic indicators based on statistical annual standards for evaluating water welfare were selected by examining domestic and foreign water resource-related indicators. The level of water welfare was evaluated relative to 23 cities and counties in Daegu and Gyeongsangbuk-do using data from the Statistical yearbook, and places with high value of indicators urbanization and large populations were excellent in the infrastructure field, but overall analysis showed that small and medium-sized cities had higher levels. It is judged that it is necessary to develop continuous research and indicators that can evaluate and quantify the level of physical welfare that the people can feel by utilizing the results of this study. In future studies, it is necessary to systematically evaluate the level of water welfare by local governments in Korea through more diverse evaluation items and detailed indicators for each item so that it can be used as basic data for realizing water welfare.

• Communications for Statistical Applications and Methods
• /
• v.23 no.4
• /
• pp.343-353
• /
• 2016

In doubly-censored data, an originating event time and a terminating event time are interval-censored. In certain analyses of such data, a researcher might be interested in the elapsed time between the originating and terminating events as well as regression modeling with risk factors. Therefore, in this study, we introduce a model evaluation method to measure the predictive ability of a model based on negative predictive values. We use a semiparametric estimate of the predictive accuracy to provide a simple and flexible method for model evaluation of doubly-censored survival outcomes. Additionally, we used simulation studies and tested data from a prostate cancer trial to illustrate the practical advantages of our approach. We believe that this method could be widely used to build prediction models or nomograms.