• The Korean Journal of Applied Statistics
• /
• v.22 no.1
• /
• pp.129-140
• /
• 2009

In this paper, we consider simultaneous confidence intervals for the difference of proportions between two groups taken from multivariate binomial distributions in a nonparametric way. We briefly discuss the construction of simultaneous confidence intervals using the method of adjusting the p-values in multiple tests. The features of bootstrap simultaneous confidence intervals using non-pooled samples are presented. We also compute confidence intervals from the adjusted p-values of multiple tests in the Westfall (1985) style based on a pooled sample. The average coverage probabilities of the bootstrap simultaneous confidence intervals are compared with those of the Bonferroni simultaneous confidence intervals and the Sidak simultaneous confidence intervals. Finally, we give an example that shows how the proposed bootstrap simultaneous confidence intervals can be utilized through data analysis.

• Journal of Institute of Control, Robotics and Systems
• /
• v.9 no.2
• /
• pp.159-167
• /
• 2003

This study suggests the hybrid fault diagnosis method of signed digraph (SDG) and partial least squares (PLS). SDG offers a simple and graphical representation for the causal relationships between process variables. The proposed method is based on SDG to utilize the advantage that the model building needs less information than other methods and can be performed automatically. PLS model is built on local cause-effect relationships of each variable in SDG. In addition to the current values of cause variables, the past values of cause and effect variables are inputted to PLS model to represent the Process armies. The measured value and predicted one by dynamic PLS are compared to diagnose the fault. The diagnosis example of CSTR shows the proposed method improves diagnosis resolution and facilitates diagnosis of masked multiple-fault.

• Communications for Statistical Applications and Methods
• /
• v.11 no.2
• /
• pp.399-411
• /
• 2004

A common method of handling nonresponse in sample survey is to delete the cases, which may result in a substantial loss of cases. Thus in certain situation, it is of interest to create a complete set of sample values. In this case, a popular approach is to impute the missing values in the sample by the mean or the median of responders. The difficulty with this method which just replaces each missing value with a single imputed value is that inferences based on the completed dataset underestimate the precision of the inferential procedure. Various suggestions have been made to overcome the difficulty but they might not be appropriate for public-use files where the user has only limited information for about the reasons for nonresponse. In this note, a multiple imputation method is considered to create complete dataset which might be used for all possible inferential procedures without misleading or underestimating the precision.

• The Korean Journal of Applied Statistics
• /
• v.21 no.4
• /
• pp.659-664
• /
• 2008

Missing continuous covariates are pervasive in the use of generalized linear models for medical data. Multiple imputation is the most common and easy-to-do method of dealing with missing covariate data. However, there are always serious warnings in using this method. There should be concern to make imputed values more proper. In this paper, proper imputation from posterior predictive distribution is developed for implementing with arbitrary priors. We use empirical distribution of the posterior for approximating the posterior predictive distribution, to sample from it. This method is preferable in comparison with a presented imputation method of us which uses a full model to impute missing values using available software. The proposed methods are implemented on glucocorticoid data.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
• /
• 2002.05a
• /
• pp.877-882
• /
• 2002

A new estimation model of predicting the sound absorption performance for multiple perforated plate sound absorbing system was developed using transfer matrix method. The proposed method was validated by comparing the calculated absorption coefficients of a single layer perforated plate with the values measured by the two-microphone impedance tube method far various porosity and cavity depth. The developed transfer matrix method was further applied to estimate the multiple layer perforated plates and it is shown that the estimated absorption coefficients generally agree well with the measured values.

• Transactions of the Korean Society for Noise and Vibration Engineering
• /
• v.12 no.9
• /
• pp.709-716
• /
• 2002

A practical method of predicting the sound absorption coefficient for multiple perforated-plate sound absorbing system was developed using transfer matrix method. The proposed method was validated by comparing the calculated absorption coefficients of a single layer perforated plate with the values measured by the two-microphone impedance tube method for various porosity and spacing of the perforated plate. The developed transfer matrix method was further applied to estimate the multiple layer perforated plates and it is shown that the estimated absorption coefficients agree well with the measured values.

• Journal of Korean Society of Industrial and Systems Engineering
• /
• v.23 no.55
• /
• pp.1-11
• /
• 2000

Taguchi's robust design methodology has focus only a single characteristic or response, but the quality of most products is seldom defined by a characteristics, and is rather the composite of a family of characteristics which are often interrelated and nearly always measured in a variety of units. The multiple characteristics problem is how to compromise the conflicts among the selected levels of the design parameters for each individual characteristic. In this paper, Methodology using SN ratio optimized by univariate technique is proposed and a parameter design procedure to achieve the optimal compromise among several different response variables is developed. Also, We propose a decision model to incorporates the values assigned by a group of experts on different factors in weighting decision. Using this model, SN ratio of taguchi method for each of subjective factors as well as values of weights are used in this comprehensive method for weighting decision.

• Journal of the Korea Society of Computer and Information
• /
• v.7 no.3
• /
• pp.16-22
• /
• 2002

Effective component retrieval is very essential for component based software development. Facet scheme is one of typical component retrieval methods and is being widely researched. In this paper, an efficient algorithm which supports a query with logical operator NOT for more than one facet values is presented. With this new algorithm the complexity to calculate a weighted synaptic connectivity matrix is enhanced. Also a new scheme is presented to support a query with logical operators for multiple facets.

• Journal of the Korean Data Analysis Society
• /
• v.20 no.6
• /
• pp.2711-2719
• /
• 2018

When an observable is described by a single value, the statistic significance may be estimated by construction of null distribution using permutation and counting the portion of it that exceeds the observed value by chance. Genome-wide association study usually focuses on the association measure between a single or interacting genotypes with a single phenotype. However investigation of common genotypes associated simultaneously on multiple phenotypes may involve the observables that should be described with multiple numbers. Statistical significance for such an observable would involve null distribution in multiple dimensions. In this study, extension of the p-value estimation process using null distribution in one dimension has been sought that may be applicable to two dimensional case. Comparison of the position of points within the set of points they form has been proposed to use a positioning parameter inspired by the extension of the Kolmogorov-Smirnov statistic to two dimensions.

• The Journal of Korean Academic Society of Nursing Education
• /
• v.18 no.2
• /
• pp.303-311
• /
• 2012

Purpose: This study was to examine the values of marriage, gender-role and having children, and to explore the factors impacting the values of having children by university students. Methods: A cross-sectional design and structured questionnaires were adopted for data collection of university students in September through November, 2011. Structured questionnaires were based on participants' socio-demographics and scales on values of marriage, gender role and children developed by Young-Mi Park. Descriptive statistics, t-test, one-way ANOVA, Pearson correlation coefficient and hierarchical multiple regression were applied to data analysis. Results: A total of 366 university students participated in this study. Females and nursing students had negative values toward having children and marriage and positive thoughts about the value of gender role. The value of having children was positively associated with marriage (r=.61, p<.001) and negatively with gender role (r=-.11, p<.032). Relationship between gender role and marriage was negative (r=-.28, p<.001). Hierarchical multiple regression found that the value of children was significantly predicted by the value of marriage.