• Title/Summary/Keyword: random factor

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A Study on the Methods for Assessing Construct Validity (구성 타당성 평가방법에 관한 연구)

  • 이광희;이선규;장성호
    • Journal of Korean Society of Industrial and Systems Engineering
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    • v.22 no.50
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    • pp.1-9
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    • 1999
  • The purpose of this study is to establish a basis for assessing construct validity of measures used in organizational research. The classic Campbell and Fiske's(1959) criteria are found to be lacking in their assumptions, diagnostic information, and power. The inherent confounding of measurement error with systematic trait and method effects is a severe limitation for a proper interpretation of convergent and discriminant validity. The confirmatory factor analysis(CFA) approach overcomes most of the limitations found in Campbell and Fiske's(1959) method. However, the CFA approach confounds random error with unique variance specific to a measure. The second-order confirmatory factor analysis(SOCFA) was shown to harbor rather restrictive assumptions and is unlikely to be met in practice. The first-order, multiple-informant, multiple-item(FOMIMI) model is a viable option, but it may also be of limited use because of the large number measures.

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Interacting Multiple Model Baro-Error Identification Filter (IMM 기법을 이용한 기압고도계 오차 식별 필터)

  • Whang, Ick-Ho;Ra, Won-Sang
    • Proceedings of the KIEE Conference
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    • 2007.07a
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    • pp.290-291
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    • 2007
  • Barometers can provide height information steady but its accuracy becomes poor as the air data varies due to the vehicles's moving or time's elapsing. In order to keep the accuracy in spite of the air data changes, we propose a filter for the identification of baro-errors. The baro-errors mainly consist of bias and scale factor errors which gradually varies as the air data varies. With GPS height measurements, the scale factor and bias estimator is designed by applying the interacting multiple model (IMM) filtering technique to the baro-error random walk model. The resultant estimates are used to compensate current baro-measurement to supply accurate measurements steadily.

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Design and Elucidation of Integrated Forecasting Model for Information Factor Analysis (정보인자분석(情報因子分析)을 위한 통합예측(統合豫測)모델의 설계(設計) 및 해석(解析))

  • Kim, Hong-Jae;Lee, Tae-Hui
    • Journal of Korean Society for Quality Management
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    • v.21 no.1
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    • pp.181-189
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    • 1993
  • Over the past two decades, forecasting has gained widespread acceptance as an integral part of business planning and decision making. Accurate forecasting is a prerequisite to successful planning. Accordingly, recent advances in forecasting techniques are of exceptional value to corporate planners. But most of forecasting mothods are reveal its limit and problem for precision and reliability duing to each relationship for raw data and possibility of explanation for each variable. Therefore, to construct the Integrated Forecasting Model(IFM) for Information Factor Analysis, it shoud be considered that whether law data has time lag and variables are explained. For this. following several method can be used : Least Square Method, Markov Process, Fibonacci series, Auto-Correlation, Cross-Correlation, Serial Correlation and Random Walk Theory. Thus, the unified property of these several functions scales the safety and growth of the system which may be varied time-to-time.

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A cultural and gender analysis of Compulsive Buying Behavior's core dimensions

  • LEE, Jaemin
    • The Journal of Economics, Marketing and Management
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    • v.7 no.3
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    • pp.29-43
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    • 2019
  • Research Purpose - The purpose of this study was to investigate marketing stimulation and impulsive buying of Internet shopping mall. Research Question - Despite these unstable factors, the Internet shopping mall market has become more popular than traditional distribution channels such as department stores and discount stores due to the increase in the number of Internet users, a gradual increase in the consumption of high-priced items. Research Method - The data were collected from 301 women living in Seoul, Gyeonggi, Gwangju, Daegu, and Gyeongnam province in Korea on May 2018. Statistical methods used in the study were frequency, F-test, Duncan test, factor analysis, Cronbach's α, correlation coefficient, and multiple regression. Result - All The reliability of these questions is Cronbach's α =. 775. Factor 5, which is 12.367 % explanatory power, is said to consist of three questions: price, discount bag, and no-carrying; thus, the reliability of the question is Cronbachs' α. The ratio of the five factors in body random cases was 66.096 %, and the reliability of the questions was higher than. 770 as a result of the reliability analysis.

On the Numerical Stability of Dynamic Reliability Analysis Method (동적 신뢰성 해석 기법의 수치 안정성에 관하여)

  • Lee, Do-Geun;Ok, Seung-Yong
    • Journal of the Korean Society of Safety
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    • v.35 no.3
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    • pp.49-57
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    • 2020
  • In comparison with the existing static reliability analysis methods, the dynamic reliability analysis(DyRA) method is more suitable for estimating the failure probability of a structure subjected to earthquake excitations because it can take into account the frequency characteristics and damping capacity of the structure. However, the DyRA is known to have an issue of numerical stability due to the uncertainty in random sampling of the earthquake excitations. In order to solve this numerical stability issue in the DyRA approach, this study proposed two earthquake-scale factors. The first factor is defined as the ratio of the first earthquake excitation over the maximum value of the remaining excitations, and the second factor is defined as the condition number of the matrix consisting of the earthquake excitations. Then, we have performed parametric studies of two factors on numerical stability of the DyRA method. In illustrative example, it was clearly confirmed that the two factors can be used to verify the numerical stability of the proposed DyRA method. However, there exists a difference between the two factors. The first factor showed some overlapping region between the stable results and the unstable results so that it requires some additional reliability analysis to guarantee the stability of the DyRA method. On the contrary, the second factor clearly distinguished the stable and unstable results of the DyRA method without any overlapping region. Therefore, the second factor can be said to be better than the first factor as the criterion to determine whether or not the proposed DyRA method guarantees its numerical stability. In addition, the accuracy of the numerical analysis results of the proposed DyRA has been verified in comparison with those of the existing first-order reliability method(FORM), Monte Carlo simulation(MCS) method and subset simulation method(SSM). The comparative results confirmed that the proposed DyRA method can provide accurate and reliable estimation of the structural failure probability while maintaining the superior numerical efficiency over the existing methods.

Effects of the Space Storytelling Factors for Building Artwork on Decision Making Processes of Apartment Purchasing (건축물 미술작품의 공간스토리텔링 적용이 아파트 구매의사결정에 미치는 영향)

  • Kwon, Hyeog-In;Lee, Jin-Hwa;Kim, Mi-Young
    • The Journal of the Korea Contents Association
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    • v.13 no.8
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    • pp.396-408
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    • 2013
  • The purpose of this research is to derive space storytelling factors newly among the evaluating factors of the building artwork and to present their roles and functions and to verify the effectiveness thereof. Random sampling was carried out on 204 residents who experience space storytelling in Ilsan Wi-City. The new evaluation factor was extracted by deriving the space storytelling factor through a theoretical study on the building artwork evaluation factors: formativeness factor, sociality factor, and environmental factor. And the effects of the space storytelling factor extracted in this way and the existion sculpture evaluation factor on the facilities affinity and the purchase intention were examined. This study will serve as a momentum for the building artwork to be harmonized with the surrounding fine view within urban space and to raise the quality of life of the residents.

The Effects of Creative Climate on the Regional Economic Growth and the Total Factor Productivity of Korean Finns -A Panel Study of Electric and Electronic Finns of the Industrial Complex- (창의성 여건이 지역경제 성장과 기업 생산성에 미치는 영향 연구 - 한국산업공단내 전기.전자기업을 중심으로 -)

  • Gheem, In-Choll;Han, Jae-Myung
    • International Commerce and Information Review
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    • v.12 no.4
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    • pp.67-109
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    • 2010
  • The theory of creative class has shown that the creative people are the key factor of success in regional economic growth. The creative people strengthen the economic competitiveness which is crucial to attract, cultivate and mobilize the resources of that region. In order to examine the theory of creative class for regional economic growth and firm productivity in Korea, this study uses the panel data of 492 Korean firms of the industrial complex producing electic and electronic manufactured goods. They are grouped into 10 industrial complexes among 16 metropolitan areas. Our findings demonstrate that creative class and 3Ts are related to the ratio of creative population density and the regional economic growth. Specifically the creative core class is of more significance to the regional economic growth than the creative professional class or the creative artist class. In our findings the panel analysis of random effects model shows that the talent index of 3Ts as well as the regional climates arc related to the individual firm's total factor productivity. This also reflects a conglomeration of the other regional climates statistically. On the other hand, the research and development expenditure of individual firms shows positive influence for each second consecutive year for the total factor productivity. Sales volume also contributes to the total factor productivity. In conclusion, we recommend that it is important to upgrade the level of creative climates by attracting the creative minds and R&D investment of the enterprises for regional economic growth and firm's total factor productivity.

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Comparison of Epidermal Growth Factor Receptor Mutations between Primary Tumors and Lymph Nodes in Non-small Cell Lung Cancer: a Review and Meta-analysis of Published Data

  • Wang, Feng;Fang, Ping;Hou, Dan-Yang;Leng, Zai-Jun;Cao, Le-Jie
    • Asian Pacific Journal of Cancer Prevention
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    • v.15 no.11
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    • pp.4493-4497
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    • 2014
  • Background: Epidermal growth factor receptor (EGFR) mutations in non-small cell lung cancer (NSCLC) can predict the clinical response to tyrosine kinase inhibitor (TKI) therapy. However, EGFR mutations may be different in primary tumors (PT) and metastatic lymph nodes (MLN). The aim of this study was to compare EGFR mutations between PT and the corresponding MLN in NSCLC patients, and provide some guidelines for clinical treatment using TKI therapy. Materials and Methods: A systematic review and meta-analysis was performed with several research databases. Relative risk (RR) with the 95% confidence interval (CI) were used to investigate the EGFR mutation status between PT and the corresponding MLN. A random-effects model was used. Results: 9 publications involving 707 patients were included in the analysis. It was found that activation of EGFR mutations identified in PT and the corresponding MLN was 26.4% (187/707) and 19.9% (141/707), respectively. The overall discordance rate in our meta-analysis was 12.2% (86/707). The relative risk (RR) for EGFR mutation in PT relative to MLN was 1.33 (95%CI: 1.10-1.60; random-effects model). There was no significant heterogeneity between the studies ($I^2$=5%, p=0.003). Conclusions: There exists a considerable degree of EGFR mutation discrepancy in NSCLC between PT and corresponding MLN, suggesting that tumor heterogeneity might arise at the molecular level during the process of metastasis.

Data Acquisition of Time Series from Stationary Ergodic Random Process Spectrums (정상 에르고드성을 가지는 확률과정 스펙트럼에 대한 합리적 시계열 데이터 확보)

  • Park, Jun-Bum;Kim, Kyung-Su;Choung, Joon-Mo;Kim, Jae-Woo;Yoo, Chang-Hyuk;Ha, Yeong-Su
    • Journal of Ocean Engineering and Technology
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    • v.25 no.2
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    • pp.120-126
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    • 2011
  • The fatigue damages in structural details of offshore plants can be accumulated due to various environmental loadings such as swell, wave, wind and current. It is known that load histories acting on mooring and riser systems show stationary and ergodic bimodal wide-banded process. This paper provides refined approach to obtain time signals representing stress range histories from wide-banded bimodal spectrum which consists of ideally narrow-banded and fully separated two spectrums. Variations of the probabilistic characteristics for time signals according to frequency and sampling time increments are compared with the reference data to be the probabilistic characteristics such as zero-crossing period, peak period, and irregularity factor obtained from an assumed ideal spectrum. It is proved that the sampling time increment more affects on the probabilistic characteristics than frequency increment. The fatigue damages according to the frequency and sampling time increments are also compared with the ones with minimum increment condition which are thought to be exact fatigue damage. It is concluded that the maximum sampling time increment to obtain reliable time signals should be determined that ratio of applied maximum sampling time increment and minimum period is less than approximately 0.08.

Speech Recognition and Its Learning by Neural Networks (신경회로망을 이용한 음성인식과 그 학습)

  • 이권현
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.16 no.4
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    • pp.350-357
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    • 1991
  • A speech recognition system based on a neural network, which can be used for telephon number services was tested. Because in Korea two different cardinal number systems, a koreanic one and a sinokoreanic one, are in use, it is necessary that the used systems is able to recognize 22 discret words. The structure of the neural network used had two layers, also a structure with 3 layers, one hidden layreformed of each 11, 22 and 44 hidden units was tested. During the learning phase of the system the so called BP-algorithm (back propagation) was applied. The process of learning can e influenced by using a different learning factor and also by the method of learning(for instance random or cycle). The optimal rate of speaker independent recognition by using a 2 layer neural network was 96%. A drop of recognition was observed by overtraining. This phenomen appeared more clearly if a 3 layer neural network was used. These phenomens are described in this paper in more detail. Especially the influence of the construction of the neural network and the several states during the learning phase are examined.

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