• Title/Summary/Keyword: Variance of Analysis

Search Result 6,248, Processing Time 0.036 seconds

Development of a Scale for Alcohol Drinking Prevention Behavior in Early Elementary School Based on Ajzen's Theory of Planned Behavior (초등학교 저학년 학생의 음주예방행위 예측변수 측정도구 개발 - Ajzen의 계획적 행위이론 기반 -)

  • Kim, Younkyoung;Lee, Chong Mi;Kang, Seo Young
    • Journal of Korean Academy of Nursing
    • /
    • v.50 no.2
    • /
    • pp.210-227
    • /
    • 2020
  • Purpose: This study aimed to develop a scale to measure variables related to alcohol drinking prevention behavior in early elementary school, based on the theory of planned behavior. Methods: A scale was developed to measure variables related to alcohol drinking prevention behavior. Initial items for direct evaluation were constructed through a literature review, and those for belief-based indirect measure were generated through interviews with 30 second- and third-grade elementary school students. The collected data from 286 third-grade elementary school students were then subjected to item analysis, exploratory and confirmative factor analysis, criterion-related validity testing, and internal consistency assessment. Results: The final scale consisted of 35 items. Intention, attitudes, subjective norms, and perceived behavioral control explained 82.7% of the variance; behavioral beliefs, normative beliefs, and control beliefs explained 65.6% of the variance; and evaluation of outcome, motivation to comply, and power of control beliefs explained 72.8% of the variance. The confirmatory factor analysis indicated that the theoretical models had a satisfactory goodness of fit. Criterion-related validity was confirmed between the direct evaluation variables and the indirect measure variables (attitudes r=.64, p<.001; subjective norms r=.39, p<.001; perceived behavioral control r=.62, p<.001). Cronbach's α was .89 for the direct evaluation variables and .93 for the indirect measure variables. Conclusion: The scale developed in this study is valid and reliable. It could be used to measure and explain variables related to alcohol drinking prevention behavior in early elementary school.

Hedging effectiveness of KOSPI200 index futures through VECM-CC-GARCH model (벡터오차수정모형과 다변량 GARCH 모형을 이용한 코스피200 선물의 헷지성과 분석)

  • Kwon, Dongan;Lee, Taewook
    • Journal of the Korean Data and Information Science Society
    • /
    • v.25 no.6
    • /
    • pp.1449-1466
    • /
    • 2014
  • In this paper, we consider a hedge portfolio based on futures of underlying asset. A classical way to estimate a hedge ratio for a hedge portfolio of a spot and futures is a regression analysis. However, a regression analysis is not capable of reflecting long-run equilibrium between a spot and futures and volatility clustering in the conditional variance of financial time series. In order to overcome such defects, we analyzed KOSPI200 index and futures using VECM-CC-GARCH model and computed a hedge ratio from the estimated conditional covariance-variance matrix. In real data analysis, we compared a regression and VECM-CC-GARCH models in terms of hedge effectiveness based on variance, value at risk and expected shortfall of log-returns of hedge portfolio. The empirical results show that the multivariate GARCH models significantly outperform a regression analysis and improve hedging effectiveness in the period of high volatility.

Sensory Profiling of Commercial Korean Distilled Soju (시판 증류식 소주의 관능특성 분석)

  • Lee, Seung-Joo;Park, Cheon-Soo;Kim, Ho-Kyung
    • Korean Journal of Food Science and Technology
    • /
    • v.44 no.5
    • /
    • pp.648-652
    • /
    • 2012
  • The sensory characteristics of nine commercially distilled soju samples were determined by sensory descriptive analysis. Eight aroma attributes, as well as four flavor/taste attributes, and six mouth-feel related attributes were evaluated by 9 judges. The descriptive data set was initially analyzed for a significant overall product effect by employing a three-way mixed model analysis of variance (judges, samples, and replications) as well as two-way interactions, with judges treated as random. In addition, correlations between mean attribute ratings were calculated, and a principal component analysis (PCA) of the mean attribute ratings employing the covariance matrix was conducted. Based on the PCA, distilled soju samples were primarily separated along the first principal component, which accounted for 66% of the total variance between the samples, with high intensities of 'alcohol taste' and 'alcohol aroma' versus 'yeast aroma'. The second principal component accounted for 14% of the total variance. Soju containing high alcohol showed stronger intensities of 'bitterness', 'alcohol taste', 'alcohol aroma', as well as all mouth-feel attributes.

Contextual and Individual Determinants of Mental Health: A Cross-sectional Multilevel Study in Tehran, Iran

  • Sajjadi, Homeira;Harouni, Gholamreza Ghaedamini;Rafiey, Hassan;Vaez-Mahdavi, Mohammadreza;Vamegh, Meroe;Kamal, Seyed Hossein Mohaqeqi
    • Journal of Preventive Medicine and Public Health
    • /
    • v.53 no.3
    • /
    • pp.189-197
    • /
    • 2020
  • Objectives: Our aim was to answer the following questions: (1) Can mental health variance be partitioned to individual and higher levels (e.g., neighborhood and district); (2) How much (as a percentage) do individual-level determinants explain the variability of mental health at the individual-level; and (3) How much do determinants at the neighborhood- or district-level explain the variability of mental health at the neighborhood- or district-level? Methods: We used raw data from the second round of the Urban Health Equity Assessment and Response Tool in Tehran (in 2012-2013, n=34 700 samples nested in 368 neighborhoods nested in 22 districts) and the results of the official report of Tehran's Center of Studies and Planning (in 2012-2013, n=22 districts). Multilevel linear regression models were used to answer the study questions. Results: Approximately 40% of Tehran residents provided responses suggestive of having mental health disorders (30-52%). According to estimates of residual variance, 7% of mental health variance was determined to be at the neighborhood-level and 93% at the individual-level. Approximately 21% of mental health variance at the individual-level and 49% of the remaining mental health variance at the neighborhood-level were determined by determinants at the individual-level and neighborhood-level, respectively. Conclusions: If we want to make the most effective decisions about the determinants of mental health, in addition to considering the therapeutic perspective, we should have a systemic or contextual view of the determinants of mental health.

Affecting Factors of Deviant Behaviors of Korean High School Students (고등학생의 일탈행동 영향요인 분석)

  • Yoon Young-Mi;Choi Myung-Sook
    • Child Health Nursing Research
    • /
    • v.9 no.3
    • /
    • pp.323-331
    • /
    • 2003
  • Purpose: The purpose of this study is to analyze the factors affecting Deviant Behaviors of Korean High school Students. Method: Data was collected from October 8 to 31, 2002. The subjects for this study were 697 Korean High school Students(boys 347, girls 350), recruited from two High School located in Seoul. Data collection was conducted through the use of 6 Questionnaire that modified by the investigator. The data was analyzed by the SPSS win 10.0 program using Descriptive statistics, Pearson Correlation coefficient and stepwise multiple regression. Result: 1) The mean of total item score the Deviant Behaviors scales was 1.59, which was slightly low. 2) There was a significant correlation between Deviant Behaviors, Type A Personality, Aggression, Impulsivity, Stress and Social Support(γ= .11 ~ .65, p<.001), but It was no significant correlation Type A Personality and Stress(γ= -.01). 3) Stepwise multiple regression analysis showed that (1) Impulsivity, Social Support and Type A Personality were the predictors of Deviant Behaviors and account for 18.6% of the variance in Deviant Behaviors. (2) Impulsivity account for 3.6% of the variance in Deviant Behaviors in Subjects with a lower degree of score the Deviant Behaviors. Impulsivity and Social Support account for 23.2% of the variance in Deviant Behaviors in subjects with higher degree of score the Deviant Behaviors. (3) Impulsivity account for 18.3% of the variance in Deviant Behaviors in High school girls (n=350). Impulsivity and Social Support account for 20.1% of the variance in Deviant Behaviors in High school boys (n=347). Conclusion: Impulsivity and Social Support account for Deviant Behaviors of High school Students. Therefore it is necessary to develop nursing intervention to reduce the level of Impulsivity, to increase the Social Support in order to decrease the Deviant Behaviors.

  • PDF

Postoperative Flat Back : Contribution of Posterior Accessed Lumbar Interbody Fusion and Spinopelvic Parameters

  • Kim, Jin Kwon;Moon, Byung Gwan;Kim, Deok Ryeng;Kim, Joo Seung
    • Journal of Korean Neurosurgical Society
    • /
    • v.56 no.4
    • /
    • pp.315-322
    • /
    • 2014
  • Objective : Posterior accessed lumbar interbody fusion (PALIF) has a clear objective to restore disc height and spinal alignment but surgeons may occasionally face the converse situation and lose lumbar lordosis. We analyzed retrospective data for factors contributing to a postoperative flat back. Methods : A total of 105 patients who underwent PALIF for spondylolisthesis and stenosis were enrolled. The patients were divided according to surgical type [posterior lumbar inter body fusion (PLIF) vs. unilateral transforaminal lumbar interbody fusion (TLIF)], number of levels (single vs. multiple), and diagnosis (spondylolisthesis vs. stenosis). We measured perioperative index level lordosis, lumbar lordosis, pelvic tilt, sacral slope, pelvic incidence, and disc height in standing lateral radiographs. The change and variance in each parameter and comparative group were analyzed with the paired and Student t-test (p<0.05), correlation coefficient, and regression analysis. Results : A significant perioperative reduction was observed in index-level lordosis following TLIF at the single level and in patients with spondylolisthesis (p=0.002, p=0.005). Pelvic tilt and sacral slope were significantly restored following PLIF multilevel surgery (p=0.009, p=0.003). Sacral slope variance was highly sensitive to perioperative variance of index level lordosis in high sacral sloped pelvis. Perioperative variance of index level lordosis was positively correlated with disc height variance ($R^2=0.286$, p=0.0005). Conclusion : Unilateral TLIF has the potential to cause postoperative flat back. PLIF is more reliable than unilateral TLIF to restore spinopelvic parameters following multilevel surgery and spondylolisthesis. A high sacral sloped pelvis is more vulnerable to PALIF in terms of a postoperative flat back.

Shape Optimization of the Lower Control Arm using the Characteristic Function and the Fatigue Analysis (특성함수와 피로해석을 이용한 로워컨트롤암의 형상최적설계)

  • Park Youngchul;Lee Donghwa
    • Transactions of the Korean Society of Automotive Engineers
    • /
    • v.13 no.1
    • /
    • pp.119-125
    • /
    • 2005
  • The current automotive is seeking the improvement of performance, the prevention of environmental pollution and the saving of energy resources according to miniaturization and lightweight of the components. And the variance analysis on the basis of structure analysis and DOE is applied to the lower control am. We have proposed a statistical design model to evaluate the effect of structural modification by performing the practical multi-objective optimization considering weight, stress and fatigue lift. The lower control arm is performed the fatigue analysis using the load history of real road test. The design model is determined using the optimization of acquired load history with the fatigue characteristic. The characteristic function is made use of the optimization according to fatigue characteristics to consider constrained function in the optimization of DOE. The structure optimization of a lower control arm according to fatigue characteristics is performed. And the optimized design variable is D=47 m, T=36mm, W=12 mm. In the real engineering problem of considering many objective functions, the multi-objective optimization process using the mathematical programming and the characteristic function is derived an useful design solution.

Surface roughness evaluation in turning by an orthogonal array method (직교배열법에 의한 선삭가공시 표면거칠기 평가)

  • 배병중;박태준;양승한;이영문;김희술
    • Proceedings of the Korean Society of Precision Engineering Conference
    • /
    • 2000.11a
    • /
    • pp.862-865
    • /
    • 2000
  • The object of this paper is to evaluate the surface roughness using the experimental equation of surface roughness, which is developed in turning by an orthogonal array method. $L_9{3^4}$ orthogonal array method, one of fractional factorial design has been used to study effects of main cutting parameters such as cutting speed, feed rate and depth of cut, on the surface roughness. And the analysis of variance (ANOVA)-test has been used to check the significance of cutting parameters. Using the result of ANOVA-test, the experimental equation of surface roughness, which consists of only significant cutting parameter - feed rate, has been developed. The coefficient of determination of this equation is 0.962.

  • PDF

A Study on the Brand Loyalty Ready to Wear of Females (성인여성 기성복의 상표충성도에 관한 연구)

  • 이부련
    • Journal of the Korean Society of Costume
    • /
    • v.21
    • /
    • pp.219-226
    • /
    • 1993
  • The main purpose of this study is to inves-tigate brand loyalty on ready-to-wear of fe-male. The subjects were two hundred ninty females in Taegu. Using SPSS package in or-der to identify relations of clothing selection behavior and information source uses multivariate analysis of variance(MANPVA) univariate analysis of variance(ANOVA) were executed. Scheffe est a kind of post-hoc multiple comparisons methods was adapted. conclusions reached in this study are as follows: 1. Clothing purchase pattern of consumers classified brand loyal group and brand dis-loyal group. The number of people in the brand loyal group was fifty more than that of the brand disloyal group. 2. In relation of brand loyalty and clothing selection behavior brand loyal group had high scores on individuality and exhibition of clothing selection behavior. Brand dis-loyal group had high scors on economy practicality courtesy facility. 3. In difference of information uses on brand loyalty brand loyal group had high scores on printed-information source, broadcast-ing-information source broadcast-ing-information sources. Among them brand loyal group particularly used printed-infor-mation source more than brocasting infor-mation source. On the contray brand dis-loyal group have high scores on human-in-formation source.

  • PDF

Expressions for Expectations and Variances of Cycle Times for Yard Cranes by Considering Dependencies among Time Elements

  • Lee, Byung-Kwon;Kim, Kap-Hwan;Yun, Won-Young
    • Industrial Engineering and Management Systems
    • /
    • v.10 no.4
    • /
    • pp.255-263
    • /
    • 2011
  • During the design process of a terminal, the handling capacity of a container yard needs to be evaluated in advance. This study suggests formulas for estimating the expectations and the variances of cycle times for various types of operations of a yard crane. Statistical analysis is used to estimate the expectations and variances. The main focus of this study is to show the impact of interdependencies among handling time elements on the expectation and variance of the cycle times; these interdependencies have not been considered in previous studies. Numerical experiments are done for evaluating the difference in the variance of cycle times and the waiting of trucks between the cases with and without the consideration of interdependencies.