• Title/Summary/Keyword: a model validity

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A Study on the Statistical Model Validation using Response-adaptive Experimental Design (반응적응 시험설계법을 이용하는 통계적 해석모델 검증 기법 연구)

  • Jung, Byung Chang;Huh, Young-Chul;Moon, Seok-Jun;Kim, Young Joong
    • Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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    • 2014.10a
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    • pp.347-349
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    • 2014
  • Model verification and validation (V&V) is a current research topic to build computational models with high predictive capability by addressing the general concepts, processes and statistical techniques. The hypothesis test for validity check is one of the model validation techniques and gives a guideline to evaluate the validity of a computational model when limited experimental data only exist due to restricted test resources (e.g., time and budget). The hypothesis test for validity check mainly employ Type I error, the risk of rejecting the valid computational model, for the validity evaluation since quantification of Type II error is not feasible for model validation. However, Type II error, the risk of accepting invalid computational model, should be importantly considered for an engineered products having high risk on predicted results. This paper proposes a technique named as the response-adaptive experimental design to reduce Type II error by adaptively designing experimental conditions for the validation experiment. A tire tread block problem and a numerical example are employed to show the effectiveness of the response-adaptive experimental design for the validity evaluation.

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A new discrete-time robot model and its validity test

  • Lai, Ru;Ohkawa, Fujio;Jin, Chunzhi
    • 제어로봇시스템학회:학술대회논문집
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    • 1997.10a
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    • pp.807-810
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    • 1997
  • Digital control of robot manipulator employs discrete-time robot models. It is important to explore effective discrete-time robot models and to analyze their properties in control system designs. This paper presents a new type discrete-time robot model. The model is derived by using trapezoid rule to approximate the convolution integral term, then eliminating nonlinear force terms from robot dynamical equations. The new model obtained has very simple structure, and owns the properties of independence to the nonlinear force terms. According to evaluation criteria, three aspects of the model properties: model accuracy, model validity range and model simplicity are examined and compared with commonly used discrete-time robot models. The validity of the proposed model and its advantages to control system designs are verified by simulation results.

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Development of a Wellness Index for Workers (근로자를 위한 웰니스지표 개발)

  • Choi, Moon-Jong;Son, Chang-Sik;Kim, Jinsu;Ha, Yeongmi
    • Journal of Korean Academy of Nursing
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    • v.46 no.1
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    • pp.69-78
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    • 2016
  • Purpose: The purpose of this study was to develop a wellness index for workers (WIW) and examine the validity and reliability of the WIW for assessing workers' wellness. Methods: The developmental process for the instrument included construction of a conceptual framework based on a wellness model, generation of initial items, verification of content validity, preliminary study, extraction of final items, and psychometric testing. Content validity was verified by 4 experts from occupational health nursing and wellness disciplines. The construct validity, convergent validity and discriminant validity were examined with confirmatory factor analysis. The reliability was examined with Cronbach's alpha. The participants were 494 workers from two workplaces. Results: Eighteen items were selected for the final scale, and the results of the confirmatory factor analysis supported a five-factor model of wellness with acceptable model fit, and factors named as physical emotional social intellectual occupational wellness. The convergent and discriminant validity were also supported. The Cronbach's alpha coefficient was .91. Conclusion: The results indicate that the WIW is a valid and reliable instrument to comprehensively assess workers' wellness, and to provide basic directions for developing workplace wellness program.

Validity Evaluation of Determination Methods of Effective Concrete Strut Strength (콘크리트 스트럿 유효강도 결정방법의 적합성 평가)

  • 윤영묵
    • Proceedings of the Korea Concrete Institute Conference
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    • 2003.11a
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    • pp.595-599
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    • 2003
  • For implementation of the strut-tie model approach to the practical analysis and design of structural concrete, the effective strengths of concrete struts in a strut-tie model, which have a crucial effect on the determination of strut and tie forces and the validity verification of strut-tie model's geometric compatibility condition, have to be determined accurately. In this study, the validity of the methods for determining the effective strengths of concrete struts was evaluated by conducting the strut-tie model analyses of the three reinforced concrete deep beams tested to failure with the effective strengths of concrete struts obtained from the suggested determination methods.

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Validity and Applicability of Clinical Ladder System Model for Nurses (간호사 임상경력관리체계 모형 타당성 및 적용가능성 검증연구)

  • Cho, Myung Sook;Kwon, In Gak;Kim, Kyung Hee;Kim, Mee Soon;Cho, Yong Ae
    • Journal of Korean Clinical Nursing Research
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    • v.23 no.3
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    • pp.281-292
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    • 2017
  • Purpose: The purpose of this study was to verify the validity and applicability of the Clinical Ladder System(CLS) Model for nurses and to suggest a model for nurses in general hospitals as well as tertiary hospitals. Methods: After refining questionnaires through focus group participation, a survey was carried out with 50 nurse managers and 500 staff nurses from 6 tertiary hospitals and 4 general hospitals. S-CVI and i-CVI for validity and applicability were calculated. Differences in validity and applicability by the type of hospitals and characteristics of respondents were analyzed using t-test and ANOVA. Results: S-CVI for validity and applicability of the CLS model were over 0.8 in two types of hospitals and the validity and applicability of the CLS model were confirmed. No differences were found in the total score for validity between the 2 types of hospitals, but in applicability, general hospitals had significantly lower applicability than tertiary hospitals. Some items showed difference according to characteristics of the respondents. CLS models were postulated based on the study results. Conclusion: The CLS model refined through this study can be used for nurses. In application, modifications are needed according to the conditions of each hospital.

Multi-facet Analysis on Validity of Sasang Type Diagnostic Test (사상체질 진단검사 타당성 분석에 대한 연구)

  • Lee, Soo-Jin;Kim, Myoung-Geun;Chae, Han
    • The Journal of Korean Medicine
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    • v.29 no.1
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    • pp.7-14
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    • 2008
  • Purpose : The purpose of study was to develop generalized validity evaluation methods and terms for Sasang type diagnostic tests. Methods : A generalized statistical evaluation model for Sasang typology was suggested and generalized validity evaluation indices were proposed with this model. Results : The usefulness of validity evaluations, such as sensitivity and specificity values, were confirmed by the systematic review of the data from previously reported studies. Conclusion :Major obstacles in the multi-facet analysis and systematic review for Sasang type diagnostic tests were discussed with this test validity study.

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Attitude toward the Website for Apparel Shopping (Part I): Measurement Model Testing (의류 쇼핑 웹사이트 태도 형성 모델 연구 (제1보) -웹사이트 속성, 웹사이트 쇼핑가치, 웹사이트 태도 측정모형 검증-)

  • 홍희숙
    • Journal of the Korean Society of Clothing and Textiles
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    • v.28 no.11
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    • pp.1482-1494
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    • 2004
  • This study identified convergent validity and discriminant validity of measurement variables by factor analysis using Spss program and tested covariance measurement model including latent variables such as the website attributes (interactivity, search and visual information of website), shopping values(utilitarian and hedonic value) and attitude toward website by AMOS program. The data were collected from a sample of 271 internet shopper of university students(male: 82, female: 189). They visited the website for apparel shopping and, after searching a casual clothing which they wanted to buy, requested to answer the questionnaire. The results were as follows: Variables that reduce validity were deleted in the several steps of factor analysis and initial measurement model testing. Final measurement model was constructed by valid variables was accepted. This measurement model will be input for testing causal research model that can explain how attributes of the website influences on consumer attitude toward the website.

The Verification of the Reliability and Validity of Special Needs Education Assessment Tool (SNEAT) in Miyagi, Japan

  • HAN, Changwan;KOHARA, Aiko
    • Proceedings of the Korea Contents Association Conference
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    • 2016.05a
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    • pp.383-384
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    • 2016
  • The Special Needs Education Assessment Tool (SNEAT) were verified of reliability and validity. However, the reliability and validity has been verified is only Okinawa Prefecture, the national data has not been analyzed. Therefore, this study aimed to verify the reliability and construct validity of SNEAT in Miyagi Prefecture as part of the national survey. SNEAT using 55 children collected from the classes on independent activities of daily living for children with disabilities in Miyagi Prefecture between November and December 2015. Survey data were collected in a longitudinal prospective cohort study. The reliability of SNEAT was verified via the internal consistency method; the coefficient of Cronbach's ${\alpha}$ were over 0.7. The validity of SNEAT was also verified via the latent growth curve model. SNEAT is valid based on its goodness-of-fit values obtained using the latent growth curve model, where the values of comparative fit index (0.997), tucker-lewis index (0.996) and root mean square error of approximation (0.025) were within the goodness-of-fit range. These results indicate that SNEAT has high reliability and construct validity.

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A Study on Developing a Model for Evaluating the Validity of New School Construction (학교(學校) 신축(新築) 타당성(妥當性) 평가(評價) 모형(模型) 개발(開發)에 관한 연구(硏究))

  • Lee, Hwa-Ryong
    • Journal of the Korean Institute of Educational Facilities
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    • v.12 no.5
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    • pp.47-56
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    • 2005
  • Reports on population movement(2000-2030) by the National Statistical Office show that the number of elementary school age population will be decreased by 1.4million from 2005 to 2020. It will effect both school size and the policies for school facilities, which have focused on downsizing class as the high standard of OECD nations. As the unfolding evidence is emerging that a number of schools and classes will be emptied out by 2030. This study aims at developing a model for evaluating the validity of school establishment, which would help more reasonable decision-making for new school construction and the class extension in the existing schools. It classifies two different ways in founding a new school - school establishment in a residential developing site and school establishment for solving a overcrowd class. It proposes the assesment items and the methods for evaluating its validity. In the end, it suggests an assesment model which the district educational offices can use in the course of planning the student accomodations to schools and making decisions for new school construction and the class extension in the existing schools. This study would be expected to help the reasonable expenditure for school facilities and to restrict overbuilding of surplus classes.

Validity and reliability of simplified subjective career success inventory for dental hygienist (치과위생사용 단축형 주관적 경력성공 측정도구의 타당도와 신뢰도)

  • Park, Soo-Auk;Cho, Young-Sik
    • Journal of Korean society of Dental Hygiene
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    • v.21 no.2
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    • pp.171-182
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    • 2021
  • Objectives: Recently, subjective career success has been used as a criterion for evaluating career success. The purpose of this study was to develop and evaluate a simplified subjective career success inventory for dental hygienists. Methods: Subfactors of the subjective career success inventory consisted of career satisfaction, employability, and job satisfaction. The validity and reliability of the existing tools were evaluated through the basic items composition, content validity index (CVI), preliminary survey, and main survey process according to dental hygienists. The preliminary survey was composed of 35 questions by verifying the content validity twice from the existing 63 questions, and the main survey was conducted with a total of 12 questions. Samples were conveniently extracted from dental hygienists with a clinical career of ≥3 years and surveyed online from March 12, 2020 to June 30, 2020. Data of 320 people were collected, of which 284 were finally analyzed. The validity and reliability were analyzed using SPSS 18.0 and AMOS 18.0 (p<0.05). Results: The subjective career success was a shortened inventory composed of nine questions, and the overall reliability was Cronbach's α=0.841. Using exploratory factor analysis, three factors were extracted. As a result of the confirmatory factor analysis, each measurement variable significantly explained the latent factor, and the fit of the model was appropriate. The fit of the model was appropriate for the structural equation model. Among the sub-factors of subjective career success, career satisfaction and job satisfaction had a significant effect on intention to stay (p<0.05). Conclusions: The simplified subjective career success inventory developed for dental hygienists was found was found to be a useful tool in terms of reliability and validity.