• Communications for Statistical Applications and Methods
• /
• v.20 no.3
• /
• pp.225-233
• /
• 2013

The linear support vector machine(SVM) is motivated by the maximal margin separating hyperplane and is a popular tool for binary classification tasks. Many studies exist on the consistency properties of SVM; however, it is unknown whether the linear SVM is consistent for estimating the optimal classification boundary even in the simple case of two Gaussian classes with a common covariance, where the optimal classification boundary is linear. In this paper we show that the linear SVM can be inconsistent in the univariate Gaussian classification problem with a common variance, even when the best tuning parameter is used.

• Communications for Statistical Applications and Methods
• /
• v.26 no.6
• /
• pp.635-644
• /
• 2019

Class probability is a fundamental target in classification that contains complete classification information. In this article, we propose a class probability estimation method when the predictor is functional. Motivated by Wang et al. (Biometrika, 95, 149-167, 2007), our estimator is obtained by training a sequence of functional weighted support vector machines (FWSVM) with different weights, which can be justified by the Fisher consistency of the hinge loss. The proposed method can be extended to multiclass classification via pairwise coupling proposed by Wu et al. (Journal of Machine Learning Research, 5, 975-1005, 2004). The use of FWSVM makes our method model-free as well as computationally efficient due to the piecewise linearity of the FWSVM solutions as functions of the weight. Numerical investigation to both synthetic and real data show the advantageous performance of the proposed method.

• Journal of the Korean Society of Clothing and Textiles
• /
• v.19 no.6
• /
• pp.895-910
• /
• 1995

Journal of the Korean Society of Clothing and Textiles Vol. 19, No. 6 (1995) p. 895~910 The purpose of study was to estimate the consistency between brand image and shopping bag image, and also to find out the important factors which constructed the brand image. This study was conducted by means of a questionnaire survey of female students of moi or universities in Seoul. Frequency, percentage, mean, factor analysis, 1-test, ANOVA, Fisher's LSD, Coster analysis, MDS are used for data analysis. The result are as follows: 1) Brand image was devised into three factors: personality/modernity, nobility and usability. 2) The rate of consistency of brand image and shopping bag image was high in the brands of Benetton, System, Cresson, Be-art, Tomboy, Guess, Esprit, Anacapri, Mercoledi, Youngwoo in descending order. 3) The most important factor which represent the brand image was the choice of color. 4) This study found that shopping bags can be advertising media because they think that shopping bags played an important role as a walking advertising media on the street.

• The Journal of the Korea Contents Association
• /
• v.13 no.11
• /
• pp.829-844
• /
• 2013

This study performed comprehensive tests on the four hypotheses on the capital structures for the firms listed in the KOSPI during the period from 2006 to 2011. It may be of concern to find any financial profiles on firms' leverage across the book- and market-value bases since there was relatively little attention drawn to any financial changing profile of the leverage surrounding the period of the pre-and the post-global financial crises. The findings of this study may also be compared with those of the previous related literature, by which it may be expected to enhance the robustness and consistency of the results across the different classifications on capital markets. It was found that three explanatory variables such as PFT, SIZE, and RISK, were found to be the statistically significant attributes on leverage during the tested period. Moreover, the outcome by the Fisher Exact test showed that a firm belonging to each corresponding industry may possess its reversion tendency towards the industry mean and median leverage ratios.

• Investigative Magnetic Resonance Imaging
• /
• v.24 no.1
• /
• pp.38-45
• /
• 2020

Background: Differentiation of cerebellopontine angle (CPA) schwannoma from meningioma is often a difficult process to identify. Purpose: To identify imaging features for distinguishing CPA schwannoma from meningioma and to investigate the usefulness of susceptibility-weighted imaging (SWI) in differentiating them. Materials and Methods: Between March 2010 and January 2015, this study pathologically confirmed 11 meningiomas and 20 schwannomas involving CPA with preoperative SWI were retrospectively reviewed. Generally, the following MRI features were evaluated: 1) maximal diameter on axial image, 2) angle between tumor border and adjacent petrous bone, 3) presence of intratumoral dark signal intensity on SWI, 4) tumor consistency, 5) blood-fluid level, 6) involvement of internal auditory canal (IAC), 7) dural tail, and 8) involvement of adjacent intracranial space. On CT, 1) presence of dilatation of IAC, 2) intratumoral calcification, and 3) adjacent hyperostosis were evaluated. All features were compared using Chi-squared tests and Fisher's exact tests. The univariate and multivariate logistic regression analysis were performed to identify imaging features that differentiate both tumors. Results: The results noted that schwannomas more frequently demonstrated dark spots on SWI (P = 0.025), cystic consistency (P = 0.034), and globular angle (P = 0.008); schwannomas showed more dilatation of internal auditory meatus and lack of calcification (P = 0.008 and P = 0.02, respectively). However, it was shown that dural tail was more common in meningiomas (P < 0.007). In general, dark spots on SWI and dural tail remained significant in multivariate analysis (P = 0.037 and P = 0.012, respectively). In this case, the combination of two features showed a sensitivity and specificity of 80% and 100% respectively, with an area under the receiver operating characteristic curve of 0.9. Conclusion: In conclusion, dark spots on SWI were found to be helpful in differentiating CPA schwannoma from meningioma. It is noted that combining dural tail with dark spots on SWI yielded strong diagnostic value in differentiating both tumors.

• Journal of Hospice and Palliative Care
• /
• v.8 no.1
• /
• pp.37-44
• /
• 2005

Purpose: To provide the basic data in developing the nursing intervention for patients who have symptoms of insomnia after undergoing hemopoietic stem cell transplantation (HSCT). This was achieved through investigating sleep quality and sleep patterns according to admission time, and discharge time. Methods: Data was put together by studying 52 HSCT patients who have been admitted to the department of HSCT from August 2002 to August 2003, in a university hospital. Research instruments used were, PSQI for sleep quality and a specified questionnaire for sleep patterns. Results: The PSQI regarding the past mono which was measured at the last day of hospitalization, was 11.8. This was significantly higher than 5.3, which was a measurement for the past month before the hospitalization (t=11.41, P=0.000). Looking at it with 7 categories-quality of sleep, consistency of sleep, sleep period, effectiveness of sleep, sleeping disorder, usage of sleeping pills, impediment of daily life- the PSQI for a month after admission increased significantly compared to the rate measured for a month before admission. Comparing the subjects sleep pattern before and after admission, it showed a significant difference regarding time attending sleep, time it takes to sleep, wake-up time, total time of sleep, day time sleep, number of times waking up during sleep, number of usage of sleeping pills, actions that are taken during sleep disorder, reasons for insomnia. Conclusion: The PSQI score of patients who undergo hemopoietic stem cell transplantation have increased significantly after hospitalization. Compared to the change of sleep patterns when hospitalized, significant changes were observed. Therefore nursing interventions addressing sleep are needed.