• Title/Summary/Keyword: Subgroup method

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Corporate Social Responsibility and Firm Risk: Controversial Versus Noncontroversial Industries

  • ERIANDANI, Rizky;WIJAYA, Liliana Inggrit
    • The Journal of Asian Finance, Economics and Business
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    • v.8 no.3
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    • pp.953-965
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    • 2021
  • This study aims to analyze the benefits of corporate social responsibility (CSR) performance on corporate risk in controversial and non-controversial industries. The hypothesis of this study is based on the conflicting effects of industry type on CSR and firm risk. The research sample consisted of 927 companies listed on the Indonesia Stock Exchange from 2016 to 2019. The main method for data processing was the ordinary least square method and subgroup analysis as a robustness test. The findings suggest that the performance of CSR can reduce corporate risk. However, the impact was only significant for non-controversial firms and weakened for controversial industries. These results support risk management and signaling theory. Firm risk in this study reflects the company's total risk, further research can categorize it into systematic and idiosyncratic risk. Besides, the number of samples of controversial industry research is not as much as non-controversial; further research can use paired samples. Regulators can use the results to create a new policy regarding CSR implementation. This study contributes to the existing literature by showing that the ability of social responsibility to reduce corporate risk only works in non-controversial industries. This result may be due to the controversial industry receiving negative stigma from its stakeholders.

A pooled Bayes test of independence using restricted pooling model for contingency tables from small areas

  • Jo, Aejeong;Kim, Dal Ho
    • Communications for Statistical Applications and Methods
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    • v.29 no.5
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    • pp.547-559
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    • 2022
  • For a chi-squared test, which is a statistical method used to test the independence of a contingency table of two factors, the expected frequency of each cell must be greater than 5. The percentage of cells with an expected frequency below 5 must be less than 20% of all cells. However, there are many cases in which the regional expected frequency is below 5 in general small area studies. Even in large-scale surveys, it is difficult to forecast the expected frequency to be greater than 5 when there is small area estimation with subgroup analysis. Another statistical method to test independence is to use the Bayes factor, but since there is a high ratio of data dependency due to the nature of the Bayesian approach, the low expected frequency tends to decrease the precision of the test results. To overcome these limitations, we will borrow information from areas with similar characteristics and pool the data statistically to propose a pooled Bayes test of independence in target areas. Jo et al. (2021) suggested hierarchical Bayesian pooling models for small area estimation of categorical data, and we will introduce the pooled Bayes factors calculated by expanding their restricted pooling model. We applied the pooled Bayes factors using bone mineral density and body mass index data from the Third National Health and Nutrition Examination Survey conducted in the United States and compared them with chi-squared tests often used in tests of independence.

Detection of Circulating Tumor Cells in Breast Cancer Patients: Prognostic Predictive Role

  • Turker, Ibrahim;Uyeturk, Ummugul;Sonmez, Ozlem Uysal;Oksuzoglu, Berna;Helvaci, Kaan;Arslan, Ulku Yalcintas;Budakoglu, Burcin;Alkis, Necati;Aksoy, Sercan;Zengin, Nurullah
    • Asian Pacific Journal of Cancer Prevention
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    • v.14 no.3
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    • pp.1601-1607
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    • 2013
  • A determination of circulating tumor cell (CTC) effectiveness for prediction of progression-free survival (PFS) and overall survival (OS) was conducted as an adjunct to standard treatment of care in breast cancer management. Between November 2008 and March 2009, 22 metastatic and 12 early stage breast carcinoma patients, admitted to Ankara Oncology Training and Research Hospital, were included in this prospective trial. Patients' characteristics, treatment schedules and survival data were evaluated. CTC was detected twice by CellSearch method before and 9-12 weeks after the initiation of chemotherapy. A cut-off value equal or greater than 5 cells per 7.5 ml blood sample was considered positive. All patients were female. Median ages were 48.0 (range: 29-65) and 52.5 (range: 35-66) in early stage and metastatic subgroups, respectively. CTC was positive in 3 (13.6%) patients before chemotherapy and 6 (27.3%) patients during chemotherapy in the metastatic subgroup whereas positive in only one patient in the early stage subgroup before and during chemotherapy. The median follow-up was 22.0 (range: 21-23) and 19.0 (range: 5-23) months in the early stage and metastatic groups, respectively. In the metastatic group, both median PFS and OS were significantly shorter in any time CTC positive patients compared to CTC negative patients (PFS: 4.0 vs 14.0 months, Log-Rank p=0.013; and OS: 8.0 months vs. 20.5 months, Log-Rank p<0.001). OS was affected from multiple visceral metastatic sites (p=0.055) and higher grade (p=0.044) besides CTC positivity (log rank p<0.001). Radiological response of chemotherapy was also correlated with better survival (p<0.001). As a result, CTC positivity was confirmed as a prospective marker even in a small patient population, in this single center study. Measurement of CTC by CellSearch method in metastatic breast carcinoma cases may allow indications of early risk of relapse or death with even as few as two measurements during a chemotherapy program, but this finding should be confirmed with prospective trials in larger study populations.

CLUSTERING DNA MICROARRAY DATA BY STOCHASTIC ALGORITHM

  • Shon, Ho-Sun;Kim, Sun-Shin;Wang, Ling;Ryu, Keun-Ho
    • Proceedings of the KSRS Conference
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    • 2007.10a
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    • pp.438-441
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    • 2007
  • Recently, due to molecular biology and engineering technology, DNA microarray makes people watch thousands of genes and the state of variation from the tissue samples of living body. With DNA Microarray, it is possible to construct a genetic group that has similar expression patterns and grasp the progress and variation of gene. This paper practices Cluster Analysis which purposes the discovery of biological subgroup or class by using gene expression information. Hence, the purpose of this paper is to predict a new class which is unknown, open leukaemia data are used for the experiment, and MCL (Markov CLustering) algorithm is applied as an analysis method. The MCL algorithm is based on probability and graph flow theory. MCL simulates random walks on a graph using Markov matrices to determine the transition probabilities among nodes of the graph. If you look at closely to the method, first, MCL algorithm should be applied after getting the distance by using Euclidean distance, then inflation and diagonal factors which are tuning modulus should be tuned, and finally the threshold using the average of each column should be gotten to distinguish one class from another class. Our method has improved the accuracy through using the threshold, namely the average of each column. Our experimental result shows about 70% of accuracy in average compared to the class that is known before. Also, for the comparison evaluation to other algorithm, the proposed method compared to and analyzed SOM (Self-Organizing Map) clustering algorithm which is divided into neural network and hierarchical clustering. The method shows the better result when compared to hierarchical clustering. In further study, it should be studied whether there will be a similar result when the parameter of inflation gotten from our experiment is applied to other gene expression data. We are also trying to make a systematic method to improve the accuracy by regulating the factors mentioned above.

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Vegetation Type and Stand Characteristics of Natural Forest in Mt. Janggunbong, Bonghwa-Gun (봉화군 장군봉 일대 자연림의 식생유형과 임분특성)

  • Byeon, Seong-Yeob;Yun, Chung-Weon
    • Korean Journal of Environment and Ecology
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    • v.31 no.3
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    • pp.297-317
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    • 2017
  • The research has been conducted in order to classify the vegetation types of natural forest in Mt. Janggunbong, Bonghwa-Gun and establish its following characteristics of stands. Vegetation data were collected by June in 2014 to August in 2016. Based on the 71 quadrates, we carried out an analysis of species-area curve, vegetation types, importance value, species diversity, coincidence method and CCA. As a result of the species-area curve, it was showed the proper investigation, vascular plants consisted a total of 227 taxa; 67 families, 152 genera, 197 species, 3 subspecies, 27 varieties. The forest vegetation was classified into 7 vegetation units, when it comes to a community group, they are classified into the Quercus mongolica community group. As for community, Q. mongolica community group is classified into the Acer pictum subsp. mono community, Pinus koraiensis community and Q. variabilis community. As for group, A. pictum subsp. mono community is classified into Lychnis cognata group and Deutzia glabrata group. The P. koraiensis community is classified into A. komarovii group and P. koraiensis typical group. The Q. variabilis community is classified into Parthenocissus tricuspidata group and Q. variabilis typical group. As for subgroup, P. tricuspidata group is classified into P. tricuspidata typical subgroup and Salix caprea subgroup. As a result of the importance value, Q. mongolica showed highest importance value in tree layer of vegetation units 1, 2, 3, 4 and 5. Betula schmidtii showed highest importance value in tree layer of vegetation unit 6. P. densiflora showed highest importance value in tree layer of vegetation unit 7. In subtree layer, shrub layer and herb layer of vegetation units 6 and 7, Q. mongolica and Q. variabilis showed high importance value. This implying that a vegetation units 6 and 7 is predicted to be composed by Q. mongolica and Q. variabilis. As for species diversity, vegetation units 1, 2 and 3 showed high species diversity(2.130~2.353). It was considered to be due to the topographical characteristics of valley. As a result of coincidence method and CCA, altitude showed high correlation than other environmental factor.

Artificial Intelligence-Based Colorectal Polyp Histology Prediction by Using Narrow-Band Image-Magnifying Colonoscopy

  • Istvan Racz;Andras Horvath;Noemi Kranitz;Gyongyi Kiss;Henriett Regoczi;Zoltan Horvath
    • Clinical Endoscopy
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    • v.55 no.1
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    • pp.113-121
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    • 2022
  • Background/Aims: We have been developing artificial intelligence based polyp histology prediction (AIPHP) method to classify Narrow Band Imaging (NBI) magnifying colonoscopy images to predict the hyperplastic or neoplastic histology of polyps. Our aim was to analyze the accuracy of AIPHP and narrow-band imaging international colorectal endoscopic (NICE) classification based histology predictions and also to compare the results of the two methods. Methods: We studied 373 colorectal polyp samples taken by polypectomy from 279 patients. The documented NBI still images were analyzed by the AIPHP method and by the NICE classification parallel. The AIPHP software was created by machine learning method. The software measures five geometrical and color features on the endoscopic image. Results: The accuracy of AIPHP was 86.6% (323/373) in total of polyps. We compared the AIPHP accuracy results for diminutive and non-diminutive polyps (82.1% vs. 92.2%; p=0.0032). The accuracy of the hyperplastic histology prediction was significantly better by NICE compared to AIPHP method both in the diminutive polyps (n=207) (95.2% vs. 82.1%) (p<0.001) and also in all evaluated polyps (n=373) (97.1% vs. 86.6%) (p<0.001) Conclusions: Our artificial intelligence based polyp histology prediction software could predict histology with high accuracy only in the large size polyp subgroup.

A Comparison of Perceived Nursing Needs among Oncology Nurses, Patients with Non-terminal Cancer and Patients with Terminal Cancer (간호사, 비말기 암환자 및 말기 암환자가 지각한 간호요구의 중요도와 제공정도에 대한 비교)

  • Choi, Ja Yun
    • Journal of Korean Academy of Nursing
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    • v.35 no.6
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    • pp.1135-1143
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    • 2005
  • Purpose: The purpose of this study was to compare the perceived importance and the perceived caring of nursing needs among oncology nurses, patients with non-terminal cancer and patients with terminal cancer. Method: A total of 83 oncology nurses, 56 patients with non-terminal cancer and 39 patients with terminal cancer served as subjects. Data was collected based on the 4-point Likert scale using a self-administered questionnaire from Mar. to Sept. 2004. Finally, data was analyzed using mean, SD, paired-test,. and ANOVA. Results: The score of the perceived importance of nursing needs was higher than that of the perceived performance of nursing needs in all three groups. There was also a difference in the degree of perceived performance of nursing needs among the three groups. In contrast, there was no difference in the total score of the perceived importance of nursing needs among the three groups, unlike the importance of informational and physical needs as a subgroup of perceived importance, where a difference was noted. Conclusions: Strategies should be developed to narrow down these gaps between nurses and patients. In particular, informational and educational programs should be designed for patients with terminal cancer.

Implementation of Group Key Management Protocol for Multicasting Information Security (멀티캐스팅 정보보안을 위한 그룹키 관리 프로토콜 구현)

  • Hong Jong-Joon
    • Journal of the Korea Society of Computer and Information
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    • v.9 no.3
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    • pp.177-182
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    • 2004
  • The existing group key management architectures applied to a small scale routing protocols may have many overheads with key distribution. Therefore this paper proposes a group key management protocol in PIM-SM multicast group communication. This method divide multicast groups with RP, and subgroup key managers are established in each RP and can be transmitted groups keys. And this does not have needs of the data translation and the new key distribution for path change. This does not have needs of the data translation and the new key distribution for path change, so the data transmission time can be reduced.

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Effects of a Blended Learning Program on Ethical Values in Undergraduate Nursing Students (혼합학습 프로그램이 간호대학생의 윤리적 가치관에 미치는 효과)

  • Kim, Sang Dol
    • Journal of Korean Academy of Nursing Administration
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    • v.20 no.5
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    • pp.567-575
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    • 2014
  • Purpose: This study was performed to investigate the effects of a blended learning program on ethical values in undergraduate nursing students. Methods: This study was a one group pretest-posttest design. Seventy-one undergraduate nursing students who were taking a nursing ethics course at K University in S city were conveniently selected. The blended learning program was undertaken for 120 minutes one day weekly for 15 weeks. It consisted of case-based learning through an online method combined with problem-based learning offline. Scores for ethical value were measured using the ethical values scale. Results: The ethical values score increased significantly in the students after the blended learning (p=.004). Of the subgroup of ethical values human-life, relationship with collaborator, and nursing job scores increased significantly in students after the blended learning, respectively (p=.034; p<.001; p<.001), the score for area as relationship with nursing clients decreased significantly in the students after the blended learning (p<.001). Conclusion: The blended learning program was identified as an educational program which induces a positive effect on the development of ethical values in undergraduate nursing students, and in future it can be utilized in nursing ethics education.

Taxonomic Position of Korean Isolates of Rhizoctonia solani Based on RAPD and ITS Sequencing of Ribosomal DNA

  • Jeon, Young-Ah;Kim, Wan-Gyu;Kim, Dae-Ho;Kwon, Soon-Wo;Hong, Seung-Beom
    • The Plant Pathology Journal
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    • v.26 no.1
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    • pp.83-89
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    • 2010
  • Taxonomic position of 46 Korean isolates of Rhizoctonia solani which were classified into nine intraspecific groups by anastomosis and cultural characteristics was analyzed by randomly amplified polymorphic DNA (RAPD) and sequence analyses of the internal transcribed spacer (ITS) regions of ribosomal DNA. All the isolates within each group showed highly similar band patterns in RAPD. The ITS regions of the isolates within the same groups showed a high level of sequence similarity above 96.0% whereas similarities among different groups were below 94.4%. When compared with several reference strains of R. solani from foreign countries, all the Korean isolates were clustered with the foreign isolates belonging to the same groups in the phylogenetic tree. All six Korean strains of AG-4 were identified as HG-1 out of 3 subgroup of AG-4. We discussed taxonomic position of Korean isolates of R. solani and showed that sequence analysis with ITS regions could be a rapid and useful method for identification of intraspecific group of R. solani.