• Title/Summary/Keyword: Hypothesis Tests

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Neurobiological basis for learning disorders with a special emphasis on reading disorders (학습장애의 신경생물학적 기전 : 읽기장애를 중심으로)

  • Chung, Hee Jung
    • Clinical and Experimental Pediatrics
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    • v.49 no.4
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    • pp.341-353
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    • 2006
  • Learning disorders are diagnosed when the individual's achievement on standardized tests in reading, mathematics, or written expression is substantially below that expected for age, schooling, and level of intelligence. Subtypes of learning disorders may be classified into two groups, language-based type learning disorders including reading and writing disorder, and nonverbal type learning disorder (NLD) such as those relating to mathematics & visuospatial skills, and those in the autism spectrum. Converging evidence indicates that reading disorder represents a disorder within the language system and more specifically within a particular subcomponent of that system, phonological processing. Recent advances in neuroimaging technology, particularly the development of fMRI, provide evidences of a neurobiological basis for reading disorder, specifically a disruption of two left hemisphere posterior brain systems, one parieto-temporal, the other occipito-temporal. The former is the reading system for beginner reading, the latter for skilled reading. Compensatory engagement of anterior systems around the inferior frontal gyrus(Broca's area) and a posterior(right occipito-temporal) system is noted in persistent poor readers in long-term follow up study. The theoretical model proposed to explain NLD's source is not right hemisphere damage, but rather the white matter model. The working hypothesis of the white matter model is that the underdevelopment of, damage to, or dysfunction of cerebral white matter(long myelinated fibers) is the source of this disorder. The role of an evidence-based effective intervention in the remediation of children with learning disorder is discussed.

The Impact of Servitization on Firm Value : Focused on Fortune 500 Company's Alliance Announcement (서비스화(Servitization)가 기업의 시장가치에 미치는 영향에 대한 연구 : 포춘 500대 기업의 제휴공시를 중심으로)

  • Yoo, Yeon-Sung;Rhim, Ho-Sun
    • Journal of the Korean Operations Research and Management Science Society
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    • v.36 no.4
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    • pp.63-79
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    • 2011
  • In this research, we have investigated the impact of servitization on firm value focused on Fortune 500 company's alliance announcement. The Firms are categorized to understand the impact of servitization and productization. The data includes Fortune 500 companies (2009, USA). Samples used for the hypothesis tests consist of 1,057 American companies that are opened on NYSE and NASDAQ, for the years 1990 through 2010. We test four research hypotheses based upon the various theoretical perspectives in servitization. The market is selective in reacting to alliance category; service company ${\rightarrow}$ manufacturing company, service company ${\rightarrow}$ service company. The findings show that alliance is significant between service company and manufacturing company. Also, the result shows significant relationship inter-service company's alliance. We have a significant relationship between company's alliance announcement and the market value of firms and shows significant AR in financial performance. Finally, this study presents implications for manufacturing companies that pursue service-led expansion as a strategic approach and are seeking to improve market value through alliance, partnership and cooperation. Continual effort must be placed to sustain market value of the firms.

The Amount of Earnings Per Share's Adjustment and Earnings Management

  • Paricheh, Monireh;Mehrazeen, Alireza;Shiri, Mahmoud Mousavi
    • The Journal of Industrial Distribution & Business
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    • v.4 no.1
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    • pp.15-21
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    • 2013
  • Purpose - Our goal was to determine whether there is a relationship between actual profits' deviation from the profits expected in earnings per share's adjustment announcements and the degree of apparent earnings management in annual financial statements. Research design, data, and methodology - The samples consisted of 133 companies from ten industries. The companies were selected among those listed in the stock exchange, and their data were examined covering the two-year period from 2008 to 2010. Tests were conducted using a regression model and SPSS statistical software. Results - The findings indicate the following. There is no significantly positive relationship among the last earnings per share's adjustment forecast, the first earnings forecast per share, and earnings management. Moreover, the amount of the latest earnings per share's adjustment forecast relative to its first forecast is not associated with the companies' discretionary accruals items. Finally, the hypothesis that a relationship exists between companies' latest adjustments of their earnings per share and earnings management was tested the results indicate that there is no such relationship. Conclusions - The study's results suggest that the amount of earnings per share's adjustment is not a motivation for earnings management.

Foreign Remittances, Banking Sector Development and Private Sector Investment

  • GITHAIGA, Peter Nderitu
    • Asian Journal of Business Environment
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    • v.10 no.1
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    • pp.7-18
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    • 2020
  • Purpose- This study seeks to investigate the impact of foreign remittances on private sector investment and the moderating role of banking sector development in Sub-Saharan African Countries. Research design, data, and methodology-The study has used a sample of 15 Sub-Saharan African countries and data for the years 1986 - 2017. Data was obtained from the World Bank Development Indicator (WDI) Database. Panel data diagnostic tests were conducted to ascertain the suitability of the data for regression analysis. The data was analyzed through descriptive and inferential statistics, while the hypothesis was tested through hierarchical regression analysis. Results- The finding of this study indicates that foreign remittances and banking sector development had a significant and positive effect on private investment in Sub-Saharan Africa. Besides, the banking sector development significantly moderated the foreign remittances and private sector investment relationship. Conclusions- Based on the results, the study concludes that banking sector development has an important influence on foreign remittances and private sector investment nexus. Due to the antagonistic interaction between foreign remittance and banking sector development, the study recommends the use of alternative ways of channeling remittances to private investment such as; issuance of diaspora bonds and appeal for direct investment by citizens living abroad.

Improvement Factors on Management Performance of Global Distribution Franchise Firms

  • Coo, Byung-Mo
    • Journal of Distribution Science
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    • v.16 no.3
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    • pp.33-47
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    • 2018
  • Purpose - The purpose of this study is to derive the performance improvement factors of courier corporations that operate global franchise systems as business strategies through their brands and to determine. Research design, data, and methodology - In the first study, 129 valid questionnaire sheets were analyzed. In the second study intended to determine whether the four performance improvement factors derived in the first study have positive effects on franchisees' business performance, 781 valid questionnaire sheets secured from six GDFFs were analyzed using AMOS analysis. Results - In the first study, four performance improvement factors were derived. In the second study, hypotheses regarding whether the performance improvement factors: leadership, communication, education and training, and brand, have positive effects on franchisees' business performance were tested, and as a result, one hypothesis was rejected and three hypotheses were adopted. Conclusions - The first and largest contribution of this study is that it derived performance improvement factors from GDFFs. The second contribution is that it determined whether the performance improvement factors that were derived have positive effects on franchisees' business performance with tests. The third contribution is that it created significant implications in terms of other studies, research value, and applications in industry fields.

Study on Relationship Quality and L-Loyalty in Location-Based Service (위치기반서비스에서 관계 품질과 L-로열티에 관한 연구)

  • Jang, Sung-Hee
    • The Journal of the Korea Contents Association
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    • v.16 no.9
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    • pp.1-11
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    • 2016
  • The purpose of this study is to examine the factors influencing relationship quality and L-Loyalty in Location-Based Service (LBS). This model tests various theoretical research hypotheses relating to LBS, relationship quality, and L-Loyalty. The target population of this study is LBS users. The results of hypothesis testing are as follows. First, personalization and perceived value positively influence commitment and perceived risk negatively influence commitment. Second, personalization, ubiquity, and perceived value positively influence satisfaction and perceived risk negatively influence satisfaction. Finally, commitment and satisfaction positively influence L-Loyalty. The results of the study will provide various implications to improve relationship quality and to secure high loyalty customers in LBS.

Why is 90% Confidence Interval Used When Confidence Interval Approach is Used for Testing Equivalence? (동등성 시험을 신뢰구간을 사용하여 검정하는 경우 왜 신뢰도 90%인 신뢰구간을 사용하는가?)

  • Kang, Seung-Ho
    • The Korean Journal of Applied Statistics
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    • v.21 no.5
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    • pp.867-873
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    • 2008
  • It is a convention to use 5% significance level when a statistical test is employed for clinical data. But when a confidence interval is used for testing equivalence, 90% confidence interval has often been used. When $1-{\alpha}$ confidence interval is used for hypothesis testing, its significance level is often ${\alpha}$. So it makes a confusion that the significance level is 10% if 90% confidence interval is employed for testing equivalence. In this paper I will clarify this issue by reviewing relevant papers and conducting simulation studies. I hope that it will be beneficial to statisticians in pharmaceutical companies, CROs, university hospitals.

Decomposition of category mixture in a pixel and its application for supervised image classification

  • Matsumoto, Masao;Arai, Kohei;Ishimatsu, Takakazu
    • 제어로봇시스템학회:학술대회논문집
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    • 1992.10b
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    • pp.514-519
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    • 1992
  • To make an accurate retrieval of the proportion of each category among mixed pixels (Mixel's) of a remotely sensed imagery, a maximum likelihood estimation method of category proportion is proposed. In this method, the observed multispectral vector is considered as probability variables along with the approximation that the supervised data of each category can be characterized by normal distribution. The results show that this method can retrieve accurate proportion of each category among Mixel's. And a index that can estimate the degree of error in each category is proposed. AS one of the application of the proportion estimation, a method for image classification based on category proportion estimation is proposed. In this method all pixel in a remotely sensed imagery are assumed to be Mixel's, and are classified to most dominant category. Among the Mixel's, there exists unconfidential pixels which should be categorized as unclassified pixels. In order to discriminate them, two types of criteria, Chi square and AIC, are proposed for fitness test on pure pixel hypothesis. Experimental result with a simulated dataset show an usefulness of proposed classification criterion compared to the conventional maximum likelihood criterion and applicability of the fitness tests based on Chi square and AIC,

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The Negative Effects of University's Students Smartphone Addition on Daily Life (대학생들의 스마트폰 중독이 일상생활에 미치는 부정적 영향)

  • Ahn, Hyun Sook;Kim, Hyo Jung
    • Journal of Korea Society of Digital Industry and Information Management
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    • v.10 no.3
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    • pp.285-296
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    • 2014
  • Recently, the use of Smartphones has been widespread and changed our lives positively. Smartphones which are called as PC in the hand and spread general people rapidly are becoming a medium to use generally various functions such as internet, work, multimedia, etc. beyond the simple function of telephone communication in the past. However, the excessive use of Smartphones has also produced many side effects. The purpose of this study is to examine the Smartphone Addiction on Daily Life Impact. This model tests various theoretical research hypotheses relating to Self-Esteem, Enjoyment, Flow, Social Impact, Smartphone Addiction and Daily life impact. The proposed model is analyzed to target 299 University Students and Smart Partial Least Square(PLS) 2.0 have been utilized for deriving the study results. The Result of Hypothesis testing are as follows. First, Self-Esteem negatively influence Smartphone Addiction. Second, Enjoyment, Flow and Social Impact positively influence Smartphone Addiction. Third, Smartphone Addiction positively influence Daily Life impact. This Research makes a basic research for smart phone addiction papers that will be investigated a lot in the future.

A Study of Usage Intention on the u-Healthcare Service with Voluntariness (자발성을 고려한 u-Healthcare 서비스의 이용의도에 관한 연구)

  • Lee, Chang Won;Jang, Sung Hee
    • Journal of the Korean Operations Research and Management Science Society
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    • v.37 no.4
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    • pp.225-238
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    • 2012
  • The purpose of this study is to examine the factors influencing usage intention of u-Healthcare with voluntariness in long-term care hospitals. This model tests various theoretical research hypotheses relating to u-Healthcare, UTAUT theory and voluntariness. The proposed model is analyzed to target long-term care hospitals. Questionnaires have been collected during two months of 2010 and total 142 has been considered to be valid. Smart PLS (partial least square) 2.0 and SPSS 15.0 have been utilized for deriving the study results. The results of hypothesis testing are as follows. First, performance expectance, effort expectancy and social influence positively influence usage intention. Second, facilitation not influence usage intention. Still due to lack of technical infrastructure to promote conditions of use u-Healthcare in long-care hospitals for u-Healthcare system also considered to be not significantly affected. Finally, performance expectance to usage intention for low voluntariness group is significantly larger than those for high voluntariness group. In addition, social influence to usage intention for high voluntarines group is significantly larger than those for low voluntariness group.