• Title/Summary/Keyword: Variance of Analysis

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A Study on Factor Analytical Methods and Procedures for PLS-SEM (Partial Least Squares Structural Equation Modeling)

  • YIM, Myung-Seong
    • The Journal of Industrial Distribution & Business
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    • v.10 no.5
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    • pp.7-20
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    • 2019
  • Purpose - This study provides appropriate procedures for EFA to help researchers conduct empirical studies by using PLS-SEM. Research design, data, and methodology - This study addresses the absolute and relative sample size criteria, sampling adequacy, factor extraction models, factor rotation methods, the criterion for the number of factors to retain, interpretation of results, and reporting information. Results - The factor analysis procedure for PLS-SEM consists of the following five stages. First, it is important to look at whether both the Bartlett test of sphericity and the KMO MSA meet the qualitative criteria. Second, PAF is a better choice of methodology. Third, an oblique technique is a suitable method for PLS-SEM. Fourth, a combined approach is strongly recommended to factor retention. PA should be used at the onset. Next, it is recommended using the K1 criterion. In addition, it is necessary to extract factors that increase the total variance explanatory power through the PVA-FS. Finally, it is appropriate to select an item with a factor loading into 0.5 or higher and a communality of 0.5. Conclusions - It is expected that the accurate factor analysis processed for PLS-SEM as previously presented will help us extract more precise factors of the structural model.

Volatile Compounds for Discrimination between Beef, Pork, and Their Admixture Using Solid-Phase-Microextraction-Gas Chromatography-Mass Spectrometry (SPME-GC-MS) and Chemometrics Analysis

  • Zubayed Ahamed;Jin-Kyu Seo;Jeong-Uk Eom;Han-Sul Yang
    • Food Science of Animal Resources
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    • v.44 no.4
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    • pp.934-950
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    • 2024
  • This study addresses the prevalent issue of meat species authentication and adulteration through a chemometrics-based approach, crucial for upholding public health and ensuring a fair marketplace. Volatile compounds were extracted and analyzed using headspace-solid-phase-microextraction-gas chromatography-mass spectrometry. Adulterated meat samples were effectively identified through principal component analysis (PCA) and partial least square-discriminant analysis (PLS-DA). Through variable importance in projection scores and a Random Forest test, 11 key compounds, including nonanal, octanal, hexadecanal, benzaldehyde, 1-octanol, hexanoic acid, heptanoic acid, octanoic acid, and 2-acetylpyrrole for beef, and hexanal and 1-octen-3-ol for pork, were robustly identified as biomarkers. These compounds exhibited a discernible trend in adulterated samples based on adulteration ratios, evident in a heatmap. Notably, lipid degradation compounds strongly influenced meat discrimination. PCA and PLS-DA yielded significant sample separation, with the first two components capturing 80% and 72.1% of total variance, respectively. This technique could be a reliable method for detecting meat adulteration in cooked meat.

Analysis of young adults sentiments about the image of jan brands and awareness of jean brads under the IMCF economic environment (IMF이후의 신세대 진바지 소비자의 감성이미지 면화와 브랜드 인지도 분석)

  • 이훈자;김칠순;임정호;남영미
    • Proceedings of the Korean Society for Emotion and Sensibility Conference
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    • 1998.11a
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    • pp.273-277
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    • 1998
  • The purpose of this study was to develop a large representative data base for jeans marketing strategy. This study was to survey brand awareness and analyze brand image and consumer's seeking image. The 700 questionnaires were distributed and 656 reliable ones were used for statistical analysis. A SAS statistical package including frequency table, factor analysis, analysis of variance, Duncan's multiple range test, Peason's correlation test was used. The results are as follows: 1. Brand awareness involves "brand recall" based on asking a person to name recalled first, and "brand recognition" based on asking to identify brand name from 30 given brands. The result indicated that "Levi" was dominant for brand recall and Guess was dominant for brand recognition. 2. Regarding the brand image, the result showed that "Vov" was best represented for sophisticated 8t trendy brand images, "Storm" for sophisticated brand image, "Jambangee" for reasonable price & comfortable brand images, and "Levis" for classic & design/color brand images. 3. As a result of factor analysis on consumer's seeking image, six factors(characteristic/gay, intelligent/sexy, feminine/sophisticated, active/functional, cute/young, simple/comfortable) were found. Several factors had a relationship with demographic variables, preferred design, fashion interest.

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Finding Significant Factors to Affect Cost Contingency on Construction Projects Using ANOVA Statistical Method -Focused on Transportation Construction Projects in the US-

  • Lhee, Sang Choon
    • Architectural research
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    • v.16 no.2
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    • pp.75-80
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    • 2014
  • Risks, uncertainties, and associated cost overruns are critical problems for construction projects. Cost contingency is an important funding source for these unforeseen events and is included in the base estimate to help perform financially successful projects. In order to predict more accurate contingency, many empirical models using regression analysis and artificial neural network method have been proposed and showed its viability to minimize prediction errors. However, categorical factors on contingency cannot have been treated and thus considered in these empirical models since those models are able to treat only numerical factors. This paper identified potential factors on contingency in transportation construction projects and evaluated categorical factors using the one-way ANOVA statistical method. Among factors including project work type, delivery method type, contract agreement type, bid award type, letting type, and geographical location, two factors of project work type and contract agreement type were found to be statistically important on allocating cost contingency.

Performance analysis and operation simulation of the beamforming antenna applied to cellular CDMA basestation (셀룰러 CDMA 기지국에 beamforming 안테나를 적용하기 위한 동작 시뮬레이션 및 성능해석에 관한 연구)

  • Park, Jae-Jun;Bae, Byeong-Jae;Jang, Tae-Gyu
    • Journal of the Institute of Electronics Engineers of Korea TC
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    • v.37 no.2
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    • pp.32-45
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    • 2000
  • This paper presents the analytic derivation of the SINR, when a linear array antenna is accommodated into the cellular CDMA basestation receiver, in relation to the two major performance effecting factors in beamforming(BF) applications, i. e., the direction selectivity, which refers to the narrowness of the mainbeam width, and the direction-of-arrival(DOA) estimation accuracy. The analytically derived results are compared with the operation simulation of the receiver realized with the several BF algorithms and their agreements are confirmed, consequently verifying the correctness of the analysis and the operation simulation. In order to investigate separately the effects of the errors occurring in the direction estimation and in the interference suppression, which are the two major functional components of general BF algorithms, both the algorithms of steering BF and the minimum- variance- distortionless-response(MVDR) BF are applied to the analysis. A signal model to reflect the spatially scattering phenomenon of the RF waves entering into the .:nay antenna, which directly affects on the accuracy of the BF algorithm's direction estimation, is also suggested in this paper and applied to the analysis and the operation simulation. It is confirmed from the results that the enhancement of the direction selectivity of the away antenna is not desirable in view of both the implementation economy and the BF algorithm's robustness to the erroneous factors. Such a trade-off characteristics is significant in the sense that it can be capitalized to obtain an economic means of BF implementation that does not severely deteriorate its performance while ensuring the robustness to the erroneous effects, consequently manifesting the significance of the analysis results of this paper that can be used as a design reference in developing BF algorithms to the cellular CDMA system.

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Natural isotopes and trace element analyses in glass samples (판유리 시료에서 동위원소 및 미량원소 분석법)

  • Min, Ji-Sook;Heo, Sangcheol;Kim, Jae-Guin;Kim, Eun-Ho;Kim, Dong-Wook;Chung, Hee-Sun
    • Analytical Science and Technology
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    • v.20 no.3
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    • pp.219-226
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    • 2007
  • Glass is frequently encountered as types of materials that are submitted to forensic science laboratories as a result of trace evidence transfers. The repeatability and the reproducibility of trace element analysis were presented. An analysis of variance (ANOVA) was performed on laser ablation inductively coupled plasma spectrometric analyses of the fragments to identify the source. Pairwise comparisons were completed for all samples. In a pairwise comparison, each sample was compared to each other for a possible [n(n-1)/2] (n : numbers of the samples) total comparison to associate/discriminate samples using Tukey's HSD method. The aim of this study was to determine the utility of LA-ICP-MS for multi-element analysis of forensic samples. The 12 glass fragments from two manufacturers were collected and analyzed to identify the source. An analysis of variance (ANOVA) was performed on 31 elements in NIST 612 Trace elements in Glass. Elements were classified into four categories defined by the combination of precision and variation of inter-samples. We selected 11 elements, 209Bi, 90Zr, 121Sb, 178Hf, 59Co, 238U, 208Pb, 140Ce, 118Sn, 49Ti and 137Ba. 6 pairs out of 66 possible pairs were not distinguished when compared by 137Ba (p<0.05). However, all samples were distinguished using both 49Ti and 137Ba (p<0.05). In conclusion, multi-elemental analysis with LA-ICP-MS is a potential tecnique for the discrimination of forensic samples.

Phenotypic Diversity among 575 Cultivated Soybean Landraces Collected from Different Provinces in Korea: A Multivariate Analysis

  • Kebede Taye Desta;Yu-Mi Choi;Young-ah Jeon;Myoung-Jae Shin;Hye-myeong Yoon;Wang XiaoHan;Hyeon-seok Oh;Young-Wan Na;Ho-cheol Ko;Na-young Ro;JungYoon Yi
    • KOREAN JOURNAL OF CROP SCIENCE
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    • v.69 no.2
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    • pp.97-110
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    • 2024
  • This study investigated 575 cultivated soybean landraces from different provinces in Korea, using 17 key agromorphological traits. The studied soybeans showed wide variations in both qualitative and quantitative traits, signifying the existence of genetic diversity. The standardized Shannon-Weaver index (H') ranged from 0.3 to 1.0, with seed-related traits having an H' value higher than 0.7. Similarly, quantitative traits showed significant variation, with the coefficient of variation ranging from 7.2% for days to maturity (DM) to 62.3% for the number of pods per plant (PPP). In terms of province, the Gyeongsangbuk-do and Gyeongsangnam-do accessions differed from the other accessions, with higher proportions of green and yellow seed coats and lower proportion of black hilums. Gyeongsangnam-do accessions also showed early maturation and flowering but had the lowest average one-hundred seeds weight (HSW). In contrast, Jeollanam-do accessions flowered and matured late but had the highest average seed weight per plant (SWPP). Hierarchical cluster analysis grouped the soybeans into 12 clusters, and further statistical analysis showed significant variations in all quantitative traits (p < 0.05). Principal component analysis grouped the accessions based on the clusters. DM, PPP, HSW, and SWPP were identified as major contributors to the observed variance along the axes of the first two principal components. Correlation analysis revealed significant associations between maturity and yield-related traits. Based on their relative performance, 37 promising accessions were identified. Overall, this study highlights the diversity of recently cultivated Korean soybean landraces and provides opportunities for future metabolomic and genomic studies.

Analyzing Online Bookstore Customers Using Artificial Neura1 Network (신경망 기법을 이용한 온라인 서점 이용자들의 고객 유형 분석)

  • Jeon, Hyun-Chi;Shin, Young-Geun;Park, Sang-Sung;Kim, Myoung-Hoon;Jang, Dong-Sik
    • The Journal of the Korea Contents Association
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    • v.7 no.9
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    • pp.127-138
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    • 2007
  • Due to the development of internet technology and the steady increase of turnover at B2C market many companies put a lot of work into maintaining a good relationship with internet customers. Particularly, analyzing and understanding specific customer groups are essential for effective CRM and marketing strategy Thus, this paper proposes the method to define the customers of online bookstore into several meaningful groups. Five important factors and factor scores for each respondent are obtained by Factor Analysis. Six groups are classified by Cluster Analysis and Analysis of Variance(ANOVA) is used to verify the difference between each group.

Influence of exercise self efficacy and perceived health status according to the stage of change for exercise behaviors in older adults (운동행동 변화단계에 따른 노인의 운동 자기효능감과 지각된 건강상태 수준 변화)

  • Kim, Woo-Cheol
    • Journal of Digital Convergence
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    • v.13 no.11
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    • pp.549-559
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    • 2015
  • The purpose of this study was to verify whether there are any differences in the level of exercise self-efficacy and perceived health status according to the stage of change for exercise behaviors in older adults. The subjects consisted of 231 older adults (91 male, 140 female) by convenience sampling residing in city D. The collected dates were analyzed using one-way ANOVA, Tukey HSD, and simple regression analysis by SPSS WIN 21.0 program. Moreover, all statistical significance level was set at a=.05. The study results were as follows: Analysis of variance showed that exercise self-efficacy showed significant differences according to the stage of change for exercise behaviors, and as a result of the posthoc analysis, it was found that as the stage became higher, their exercise self-efficacy became higher as well. Perceived health status showed significant differences according to the stage of change for exercise behaviors, and as a result of the posthoc analysis, it was found that as the stage became higher, their perceived health status became higher as well. Analysis of variance showed that exercise self-efficacy and perceived health status were significantly associated with the stages of exercise behavior change. This study identified that exercise self-efficacy and perceived health status were significant variables to explain a possible relationship with exercise stages of older adults. This study provides new information to influence the development of the better health promotion and exercise intervention for older adults in the community.

A Dynamic Analysis of Import Price of Roundwood (원목수입가격(原木輸入價格)의 동태적(動態的) 분석(分析))

  • Han, Sang-Yoel;Kim, Tae-Kyun;Cho, Jae-Hwan;Choi, Kwan
    • Journal of Korean Society of Forest Science
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    • v.88 no.1
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    • pp.1-10
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    • 1999
  • The dynamic relationships among import prices of roundwood are analyzed using the time series approach. A vector autoregression(VAR) model is estimated for six import prices(New Zealand, Chile, Russia, U.S.A., PNG, and Malaysia). Then Granger's causality test, variance decomposition analysis, and impulse response function analysis are also conducted. The major results are summarized as follows : (1) The prices of New Zealand and Russia are caused by only own lagged prices. (2) The prices of Chile and PNG are effected by New Zealand, the price of PNG is effected by New Zealand and Russia, and the price of U.S.A. is effected by those of Chile and PNG, respectively. (3) An exogenous shock in New Zealand will affect the prices of New Zealand, PNG, U.S.A., Chile, Russia. (4) An exogenous shock in Chile may also affect the prices of Chile, U.S.A., Russia.

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