• Title/Summary/Keyword: frequency and correlation analysis

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Simple Statistical Tools to Detect Signals of Recent Polygenic Selection

  • Piffer, Davide
    • Interdisciplinary Bio Central
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    • v.6 no.1
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    • pp.1.1-1.6
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    • 2014
  • A growing body of evidence shows that most psychological traits are polygenic, that is they involve the action of many genes with small effects. However, the study of selection has disproportionately been on one or a few genes and their associated sweep signals (rapid and large changes in frequency). If our goal is to study the evolution of psychological variables, such as intelligence, we need a model that explains the evolution of phenotypes governed by many common genetic variants. This study illustrates simple statistical tools to detect signals of recent polygenic selection: a) ANOVA can be used to reveal significant deviation from random distribution of allele frequencies across racial groups. b) Principal component analysis can be used as a tool for finding a factor that represents the strength of recent selection on a phenotype and the underlying genetic variation. c) Method of correlated vectors: the correlation between genetic frequencies and the average phenotypes of different populations is computed; then, the resulting correlation coefficients are correlated with the corresponding alleles' genome-wide significance. This provides a measure of how selection acted on genes with higher signal to noise ratio. Another related test is that alleles with large frequency differences between populations should have a higher genome-wide significance value than alleles with small frequency differences. This paper fruitfully employs these tools and shows that common genetic variants exhibit subtle frequency shifts and that these shifts predict phenotypic differences across populations.

Analysis of Determinants of Eco-Friendly Food Purchase Frequency Before and After COVID-19 Using the Consumer Behavior Survey for Food (식품소비행태조사를 이용한 COVID-19 전후 친환경식품 구매빈도 결정요인분석)

  • Sung-tea Kim;Seon-woong Kim
    • The Korean Journal of Food And Nutrition
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    • v.36 no.4
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    • pp.222-235
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    • 2023
  • In this research, we examined the shifts in determinants influencing the frequency of eco-friendly food purchases pre- and post-COVID-19. Our analysis utilized filtered 2019-2021 Consumption Behavior Survey data from the Korea Rural Economic Institute Food, excluding any irrational responses. Given the nature of the dependent variable, a multinomial logistic regression model was employed with demographic factors, variables pertaining to food consumption behavior, and variables concerning food consumption awareness as predictors. Following the onset of the COVID-19 pandemic, an individual's level of education was observed to positively influence the frequency of eco-friendly food purchases. In contrast, income level and fluctuations in food consumption expenditure did not appear to have a discernible impact on the purchasing frequency of such eco-friendly products. Irrespective of the advent of COVID-19, variables such as the frequency of online food purchases, the utilization of early morning delivery services, dining out frequency, and the intake of health-functional foods consistently demonstrated a positive correlation with the propensity to purchase eco-friendly foods. Overall, consumers prioritizing safety, quality, and nutrition over price, taste, and convenience in their procurement decisions for rice, vegetables, meat, and processed foods exhibit an increased inclination toward the acquisition of eco-friendly food products.

Comparative Anatomy of Diffuse-Porous Woods Grown in Korea (I) -Characteristics by Simple Correlation and Principal Component Analysis- (한국산(韓國産) 산공재(散孔材)의 해부학적(解剖學的) 특성(特性)에 관한 비교연구(比較硏究)(I) -단순상관(單純相關)과 주성분(主成分) 분석(分析)에 의한 특성(特性)-)

  • Chung, Youn-Jib;Lee, Phil-Woo
    • Journal of the Korean Wood Science and Technology
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    • v.23 no.4
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    • pp.46-53
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    • 1995
  • The anatomy of Korean diffuse-porous woods, 36 families, 75 genera, 145 species, 215 specimens was described and analyzed. Sixteen wood anatomical characters, habit and phenology factors were determined by simple correlation and principal component analysis. Strong positive correlations were found between vessel element length and fiber length, ray width and ray height, simple pits of fiber wall and paratracheal parenchyma distribution. The results of principal component analysis (PCA) disclose the primitive characteristics and the direction of xylem evolution of Korean diffuse-porous woods. The xylem evolution scenario for Korean dicotyledonous woods is considered to be developed in the direction of decreasing trends of vessel frequency, vessel element length, and length/diameter(L/D) ratio of vessel element but increasing trends of vessel diameter, fiber length/vessel element length(F/V) ratio, libriform wood fibers, simple perforation, and homogeneous ray composition. Increase of vessel diameter and decrease of vessel frequency seem to be related to the improvement of conductive efficiency, and increase of the vessel element length and occurrence of scalariform perforation in vessel element may be related to enhanced of conductive safety. Also the libriform wood fibers and ray features appear to have relationship with mechanical support and nutrient metabolism, respectively.

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Application and Evaluation of Web-based Food Frequency Questionnaire for Korean Adolescents (웹 기반 시스템을 이용한 반정량적 식품섭취빈도 조사지의 적용 및 평가)

  • Yum, Jinhee;Lee, Seungmin
    • Korean Journal of Community Nutrition
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    • v.21 no.5
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    • pp.440-450
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    • 2016
  • Objectives: We previously developed a dish-based semi-quantitative food frequency questionnaire (FFQ) for Korean adolescents and reported that it had reasonable reliability and validity. The objective of the current study was to construct a web-based dietary evaluation system applying the FFQ for Korean adolescents and examine its applicability in the context of reliability and validity. Methods: A web-based food frequency questionnaire system was designed using a comprehensive approach, incorporating not only dietary data survey but also up-to-date nutrition information and individualized eating behavior guidelines. A convenience sample of 50 boys and girls aged 12~18 years agreed to participate in the study and completed the FFQ twice and 3 days of dietary recall on the developed website during a two-month period. The FFQ's reliability and validity was examined using correlation and cross classification analysis. We also measured participants' subjective levels of the web site's usability, visual effect, understanding, and familiarity. Results: Spearman correlation coefficients for reliability ranged from 0.74 (for vitamin A) to 0.94 (for energy). From cross-classification analyses, the proportion of subjects in the same intake quartile was highest for energy (82.0%) and lowest for vitamin A (56.0%). With regard to validity analysis, Spearman correlation coefficients ranged from 0.34 (for fiber) to 0.79 (for energy). The proportions of subjects in the opposite categories between the first FFQ and 3-day diet recall data were generally low from 0.00% (for fat) to 36.2% (for sodium). Average subjective levels of the website's usability, visual effect, understanding, and familiarity were all found to be over 4 points out of 5 points. Conclusions: The web-based dietary evaluation system developed can serve as a valid and attractive tool for administering FFQ to Korean adolescents.

Korean prosodic properties between read and spontaneous speech (한국어 낭독과 자유 발화의 운율적 특성)

  • Yu, Seungmi;Rhee, Seok-Chae
    • Phonetics and Speech Sciences
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    • v.14 no.2
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    • pp.39-54
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    • 2022
  • This study aims to clarify the prosodic differences in speech types by examining the Korean read speech and spontaneous speech in the Korean part of the L2 Korean Speech Corpus (speech corpus for Korean as a foreign language). To this end, the articulation length, articulation speed, pause length and frequency, and the average fundamental frequency values of sentences were set as variables and analyzed via statistical methodologies (t-test, correlation analysis, and regression analysis). The results found that read speech and spontaneous speech were structurally different in the form of prosodic phrases constituting each sentence and that the prosodic elements differentiating each speech type were articulation length, pause length, and pause frequency. The statistical results show that the correlation between articulation speed and articulation length was highest in read speech, explaining that the longer a given sentence is, the faster the speaker speaks. In spontaneous speech, however, the relationship between the articulation length and the pause frequency in a sentence was high. Overall, spontaneous speech produces more pauses because short intonation phrases are continuously built to make a sentence, and as a result, the sentence gets lengthened.

Characteristics of Groundwater Quality in Kyungnam Province (경상남도 지역의 지하수질 특성조사)

  • 김승현;이찬원;허종수
    • Journal of Environmental Science International
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    • v.7 no.6
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    • pp.859-865
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    • 1998
  • The analysis of groundwater quality in Kyungnam Province was conducted using monitoring results obtained during 1994. According to the analysis, most heavy metals and pesticides listed in Korean drinking water standards were not detected in Kyungnam Province groundwater, but arsonic and volatile organics such as TCE and PCE were detected. Four inorganic contaminants were detected and frequency of violating the standards was in order of $NO_3-N, F^-, As, NH_3-N$. Of organics, TCE and PCE were the only contaminants detected. TCE more frequently violated the standards than PCE. Correlation was investigated among contaminants detected in Kyungnam Province groundwater. The correlation results showed that high correlation existed among dissolved solids, hardness, and $SO_4^{2-}$.

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The Factors Influencing on Depression of Patients for Fibromyalgia Syndrome (섬유조직염 환자의 우울에 미치는 변인)

  • 성기월;신임희;이경희
    • Journal of Korean Academy of Nursing
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    • v.33 no.5
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    • pp.609-617
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    • 2003
  • Purpose: The purpose of this study is to understand the depression of patients for Fibromyalgia Syndrome(FMS) and to identify the factors influencing depression. Method: The instruments used here are Beck Depression Inventory in depression, the Korean Rheumatology Health Association' instruments in Self-Efficacy. Also, Pain and Fatigue was measured by Visual Graphic Rating Scale. The subject of study is 76 outpatients diagnosing FMS from rheumatism specialists at C hospital in D city. The data has been collected from Sep. 1st to Sep. 30th in 2001. For the analysis of collected data, frequency analysis, independent t-test, analysis of variance, Pearson's correlation and multiple regression analysis were used for statistical analysis with SAS statistical program. Result: General characteristics showing statistically significant difference in depression were age, education, occupation, gender, exercise and sleep in the patients with FMS. Depression for the patients with FMS has negative correlation coefficients with Self-efficacy and ADL, and positive correlation coefficients with Pain and Fatigue. The suitable regression form resulting from the multiple regression analysis to investigate the influencing factors of depression for the partients with FMS was expressed by y =50.067 - 0.278x$_1$ + 1.320x$_2$ (x$_1$: Self-Efficacy x$_2$: Fatigue) and $R^2$ =0.427. Conclusion: The factors influencing on depression of patients for FMS was Self-Efficacy, ADL, Pain, and Fatigue. Further study needs to be done identify methods of overcoming and presentation of depression in FMS.

The influence of internet-use Anatomy class on critical thinking disposition - Flipped learning method applying-

  • Kim, Jung-ae;Kim, Su-min;Yang, Dong-hwi
    • International Journal of Internet, Broadcasting and Communication
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    • v.10 no.2
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    • pp.60-67
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    • 2018
  • The purpose of this study was to examine the effects of internet-use Anatomy class, as one of the Flipped learning method, on critical thinking disposition. The class for this study was conducted from March 1 to April 10, 2018. The study involved a total of 180 people in the first year of a University located in C province. Data collection was carried out before and after the Flipped learning method application. Frequency analysis, Paired t-test, Pearson correlation, and Regression analysis were used for the analysis. According to the analysis, 28.3% of men and 71.1% of women and before applying the program analysis of correlation between Flipped learning perception and critical thinking disposition showed a significant correlation between confidence(sub-component of critical thinking) only (p<.005). Comparing the scores of critical thinking before and after the program, it was found that Truth seeking (p<.001), Open-mindness (p<.005), Confidence (p<.001), Systematicity (p<.005), Analyticity (p<.001), and Inquisitiveness (p<.001) scores had increased significantly except Maturity (p>.005). And the regression analysis of Flipped learning method applying influence on critical thinking disposition were significantly affected (p<.001). Based on the results of this study, it was possible to determine that Flipped learning method had a positive effect on critical thinking disposition.

Dilemma of Saudi Arabian Construction Industry

  • Albogamy, Abdullah;Scott, Darren;Dawood, Nashwan
    • Journal of Construction Engineering and Project Management
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    • v.3 no.4
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    • pp.35-40
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    • 2013
  • Currently, the Kingdom of Saudi Arabia (KSA) is the epicentre of building services engineering encapsulating the construction industry. On rise of technological advancements, engineers have the ease to thoroughly investigate engineering aspects. Not only engineers, but other stakeholders, tender related people, financial analysts work in parallel as well. However, there are some factors that are stumbling blocks in the way of progression including delaying factors in the construction industry. The paper provides deep insights of delaying factors regarding public building projects of the KSA. Collection of primary data was carried out by conducting a survey which comprised of 63 chief delay factors. Professionals related to construction industry were asked for ranking the factors in terms of their frequency of occurrence and degree of impact. Seven groups of risk factors are categorized and a correlation analysis is performed by identifying the correlation amongst the variables. Finally, 31 leading delay factors are extracted and reported.

Analysis on Factors Affecting the Acceleration of the Ballasted Track in Kyong-Bu High Speed Line

  • Kim, Man-Cheol
    • International Journal of Railway
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    • v.2 no.4
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    • pp.152-163
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    • 2009
  • In this paper, the correlation between the accelerations measured at the track components and the parameters affecting the acceleration is analyzed. To do it, the accelerations of each track component such as rails, sleepers and ballast are measured in Kyong-Bu high-speed Line. The RMS values of the measured accelerations are calculated and the pad stiffness, the longitudinal irregularity, running velocity and the corrugation, are considered as the parameters affecting the acceleration. By using the linear regression, the correlation coefficients are calculated to analyze the relationship between the acceleration characteristics and the parameters. Also, the 1/3 Octave analysis is calculated to analyze the dominant frequency band of the accelerations of the track components.

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