Go to the main menu
Skip to content
Go to bottom
REFERENCE LINKING PLATFORM OF KOREA S&T JOURNALS
> Journal Vol & Issue
Journal of the Korean Data and Information Science Society
Journal Basic Information
Journal DOI :
Korean Data and Information Science Society
Editor in Chief :
Volume & Issues
Volume 11, Issue 2 - Oct 2000
Volume 11, Issue 1 - Apr 2000
Selecting the target year
A Comparison of Robust Parameter Estimations for Autoregressive Models
Kang, Hee-Jeong ; Kim, Soon-Young ;
Journal of the Korean Data and Information Science Society, volume 11, issue 1, 2000, Pages 1~18
In this paper, we study several parameter estimation methods used for autoregressive processes and compare them in view of forecasting. The least square estimation, least absolute deviation estimation, robust estimation are compared through Monte Carlo simulations.
An Automatic Document Classification with Bayesian Learning
Kim, Jin-Sang ; Shin, Yang-Kyu ;
Journal of the Korean Data and Information Science Society, volume 11, issue 1, 2000, Pages 19~30
As the number of online documents increases enormously with the expansion of information technology, the importance of automatic document classification is greatly enlarged. In this paper, an automatic document classification method is investigated and applied to UseNet 20 newsgroup articles to test its efficacy. The classification system uses Naive Bayes classification algorithm and the experimental result shows that a randomly selected newsgroup arcicle can be classified into its own category over 77% accuracy.
Notes on Upper and Lower Bounds of Odds Ratio
Woo, Jung-Soo ;
Journal of the Korean Data and Information Science Society, volume 11, issue 1, 2000, Pages 31~35
We shall give upper and lower bounds of the odds ratio of an event by a slight condition of the conditional probability of events.
Lindley Type Estimators with the Known Norm
Baek, Hoh-Yoo ;
Journal of the Korean Data and Information Science Society, volume 11, issue 1, 2000, Pages 37~45
Consider the problem of estimating a
under the quadratic loss, based on a sample
. We find an optimal decision rule within the class of Lindley type decision rules which shrink the usual one toward the mean of observations when the underlying distribution is that of a variance mixture of normals and when the norm
is known, where
is the column vector of ones.
Study on the Prediction Models for the Productions of Major Food Crops
Chang, Suk-Hwan ;
Journal of the Korean Data and Information Science Society, volume 11, issue 1, 2000, Pages 47~55
In oreder to predict the productions of major crops such as rice, barely, soybean and potato in Kyongsang Puk Do as early as possible, an attempt has been made to develop some prediction model of crop yields, using the data from the Statistical Yearbooks of Agriculture, Forestry and Fisheries from 1966 through 1999. Among the various models considered,
was best fit to the planted area of the crops and
to the yields. The
values for the planted areas were
, implying good prediction, while that for rice was 0.7234 and those for barley, soybean and potato were
, Predictions have also been made for the planted areas upto the year 2005 and yield for the year 2000.
AMLE for the Gamma Distribution under the Type-I censored sample
Kang, Suk-Bok ; Lee, Hwa-Jung ;
Journal of the Korean Data and Information Science Society, volume 11, issue 1, 2000, Pages 57~64
By assuming a Type-I censored sample, we propose the approximate maximum likelihood estimators(AMLE) of the scale and location parameters of the gamma distribution. We compare the proposed estimators with the maximum likelihood estimators(MLE) in the sense of the mean squared errors(MSE) through Monte Carlo method.
A Comparative Study on Optimization Procedures to Robust Design
Kwon, Yong-Man ; Mun, In-Suk ;
Journal of the Korean Data and Information Science Society, volume 11, issue 1, 2000, Pages 65~72
Robust design is an approach to reducing performance variation of quality characteristic values in quality engineering. Taguchi parameter design has a great deal of advantages but it also has some disadvantages. The various research efforts aimed at developing alternative methods. In the Taguchi parameter design, the product-array approach using orthogonal arrays is mainly used. However, it often requires an excessive number of experiments. An alternative approach, which is called the combined-array approach, was suggested by Welch et. al. (1990) and studied by others. In this paper we make a comparative study on optimization procedures to robust design in the two different experimental design(product array, combined array) approaches the Mough the Monte Carlo simulation.
Diagnostics of partial regression and partial residual plots
Lee, Jea-Young ; Choi, Suk-Hwa ;
Journal of the Korean Data and Information Science Society, volume 11, issue 1, 2000, Pages 73~81
The variance inflation factor can be expressed by the square of the ratio of t-statistics associated with slopes of partial regression and partial residual plots. Disagreement of two sides in the interpretation can be occurred, and we analyze it with some illustrations.
On the Small Sample Distribution and its Consistency with the Large Sample Distribution of the Chi-Squared Test Statistic for a Two-Way Contigency Table with Fixed Margins
Park, Cheol-Yong ; Choi, Jae-Sung ; Kim, Yong-Gon ;
Journal of the Korean Data and Information Science Society, volume 11, issue 1, 2000, Pages 83~90
The chi-squared test statistic is usually employed for testing independence of two categorical variables in a two-way contingency table. It is well known that, under independence, the test statistic has an asymptotic chi-squared distribution under multinomial or product-multinomial models. For the case where both margins fixed, the sampling model of the contingency table is a multiple hypergeometric distribution and the chi-squared test statistic follows the same limiting distribution. In this paper, we study the difference between the small sample and large sample distributions of the chi-squared test statistic for the case with fixed margins. For a few small sample cases, the exact small sample distribution of the test statistic is directly computed. For a few large sample sizes, the small sample distribution of the statistic is generated via a Monte Carlo algorithm, and then is compared with the large sample distribution via chi-squared probability plots and Kolmogorov-Smirnov tests.
A New Estimator of Population Mean Based on Centered Balanced Systematic Sampling
Kim, Hyuk-Joo ;
Journal of the Korean Data and Information Science Society, volume 11, issue 1, 2000, Pages 91~101
We propose a new method for estimating the mean of a population which has a linear trend. The suggested estimator is based on the centered balanced systematic sampling method and the concept of interpolation and extrapolation. The efficiency of the proposed method is compared with that of existing methods.
Second Order Approximations to the Stopping Time with Fixed Proportional Accuracy
Choi, Ki-Heon ;
Journal of the Korean Data and Information Science Society, volume 11, issue 1, 2000, Pages 103~110
Suppose that there is a population of hidden objects of which the total number N is unknown. From such data, we derive second-order approximations to the stopping time with fixed proportional accuracy.
Application of In-direct Estimation for Small Area Statistics
Kim, Young-Won ; Sung, Na-Young ;
Journal of the Korean Data and Information Science Society, volume 11, issue 1, 2000, Pages 111~126
Small area estimation is becoming important in survey sampling due to a growing demand for reliable small area statistics. In estimating means, totals, and other parameters for small areas of a finite population, samplie sizes for small areas are typically small because the overall sample size is usually determined to provide specific accuracy at a much higher level of aggregation than that of small area. The usual direct estimators that use the only information which is gotten from the sample in a given small area provide unreliable estimates. However, indirect estimators utilize the information from the areas related with a given small area, that is, borrow strength from other related areas, and so give more accurate estimates than direct estimators. In this paper we investigate small area estimation methods such as synthetic, composite and empirical best linear unbiased prediction estimator, and apply them to real domestic data which is from the Survey of Hotels and Restaurants in In-Chon as of 1996 and then evaluate the performance of these methods by measuring average squared errors. This evaluation shows that indirect estimators, which are small area estimation methods, are more efficient than direct estimator.
Hierarchical Bayesian Analysis for Stress-Strength Model in Normal Case
Lee, In-Suk ; Cho, Jang-Sik ; Kang, Sang-Gil ;
Journal of the Korean Data and Information Science Society, volume 11, issue 1, 2000, Pages 127~137
In this paper, we consider hierarchical Bayesian analysis for P(Y < X) using Gibbs sampler, where X and Y are independent normal distributions with unknown means and variances, respectively. Also numerical study using real data is provided.