• Title/Summary/Keyword: Multiple Regression Analysis

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A Symptom Differentiation based on Prospective pre-post intervention design and multiple regression analysis in Korean medicine - Focus on Yang Deficiency and Blood Heat Type Psoriasis - (전향적 전후비교환자군과 다중회귀분석방법을 활용한 변증연구 - 117명 건선환자의 양허증과 혈열증를 중심으로 -)

  • Sundong Lee;Hyundo Kim;Seyoung Jung;Bo-in Kwon
    • The Journal of Korean Medicine
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    • v.44 no.2
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    • pp.1-9
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    • 2023
  • Objectives: To study symptom differentiation for yang deficiency and blood heat based on 117 psoriasis patients. Methods: Obtained frequency analysis (%), mean (%), and OR, CL(P-value) with prospective pre-post intervention design and multiple regression analysis. Results: There were no statistically significant differences as to sex, BMI, smoking and marital status, but there were statistically significant differences in variables of average age, family history, and alcohol consumption (P<0.05). There were no statistically significant differences in psoriasis symptoms as to initial age of onset, morbidity span, area of the initial onset, and the progression of psoriasis during the last three months of each patient. However, the type of psoriasis showed a statistically significant difference (p=0.011). While there were no statistically significant differences as to common cold, condition of psoriasis after recovering from the cold, skin condition, exercise, and seasonality, irregular perspiration showed significant difference (p<0.00). When confounding factors have been controlled the blood heat patient group as the comparison group, multiple regression analysis showed OR, CI(95%) of 1.06(0.31-3.63) for men, 0.28(0.08-1.06) for aged 30 to 49,0 and 0.18(0.04-0.80) for aged 50 and older. it was 0.06(0.01-0.7) for family history, 1.06(0.29-3.88) for drink alcohol, 19.90(2.53-156.7) for seasonality, and 10.28 (3.19-33.11) for perspiration problems. In these variables, Sex, age, smoking, and alcohol consumption showed no statistically significant results, but family history(p=0.049), seasonality(p=0.005), and irregular perspiration (p=0.017) were statistically significant. Conclusion: Family history, seasonality and irregular perspiration are the determining factors for yang deficiency and blood heat in psoriasis.

A Study of the Measurement of Personal Activity on Online Marketing: Focus on SNS (온라인 마케팅 활동성 측정에 대한 연구- SNS 사용자 활동을 중심으로)

  • Kim, Sooeun;Kim, Eungdo
    • Knowledge Management Research
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    • v.16 no.3
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    • pp.81-102
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    • 2015
  • With the rapid development of digital media, there has been a huge change in a way of communication, a process of information diffusion and a role of traditional media. Not like mass media, social media enables users to generate and tap into the opinions of a larger world. From that reason, social media is impacting marketing strategies. However, still social media marketing researches just focus on case study, analysis of users motivation or analysis of power user's usage pattern. Word-of-mouth has always been important especially in marketing area. In social media, word-of-mouth depends on each user that's why this research focuses on individual user's activity in SNS. I defined 4 factors (produce, diffusion, network size, activity of network size enlarge) that are effect on activity and verified hypothesis by multiple regression analysis, hierarchical regression analysis and moderated multiple regression.

Optimized Neural Network Weights and Biases Using Particle Swarm Optimization Algorithm for Prediction Applications

  • Ahmadzadeh, Ezat;Lee, Jieun;Moon, Inkyu
    • Journal of Korea Multimedia Society
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    • v.20 no.8
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    • pp.1406-1420
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    • 2017
  • Artificial neural networks (ANNs) play an important role in the fields of function approximation, prediction, and classification. ANN performance is critically dependent on the input parameters, including the number of neurons in each layer, and the optimal values of weights and biases assigned to each neuron. In this study, we apply the particle swarm optimization method, a popular optimization algorithm for determining the optimal values of weights and biases for every neuron in different layers of the ANN. Several regression models, including general linear regression, Fourier regression, smoothing spline, and polynomial regression, are conducted to evaluate the proposed method's prediction power compared to multiple linear regression (MLR) methods. In addition, residual analysis is conducted to evaluate the optimized ANN accuracy for both training and test datasets. The experimental results demonstrate that the proposed method can effectively determine optimal values for neuron weights and biases, and high accuracy results are obtained for prediction applications. Evaluations of the proposed method reveal that it can be used for prediction and estimation purposes, with a high accuracy ratio, and the designed model provides a reliable technique for optimization. The simulation results show that the optimized ANN exhibits superior performance to MLR for prediction purposes.

Development of Regression Equation for Water Quantity Estimation in a Tidal River (감조하천에서의 저수위 유량산정 다중회귀식 개발)

  • Lee, Sang Jin;Ryoo, Kyong Sik;Lee, Bae Sung;Yoon, Jong Su
    • Journal of Korean Society on Water Environment
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    • v.23 no.3
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    • pp.385-390
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    • 2007
  • Reliable flow measurement for dry season is very important to set up the in-stream flow exactly and total maximum daily load control program in the basin. Especially, in the points which tidal current effects are dominant because reliability of the low measurement decrease. The reliable measuring methods are needed. In this study, we analysis the water surface elevation difference of water surface elevation. Quantity relationship to consider tidal currents in these regions. It is known that tidal current effects from Nakdong river barrage are dominant in Samrangjin measuring station. We developed multiple regression equation with water surface elevation, quantity, and difference of water surface elevation and compared these results water measured rating curve. All of these regression equation including linear regression equation and log regression equation fits better measured data them existing water surface elevation quantity line and Among three equations, the log regression equation is best to represent the measured the rating curve in Samrangjin point. The log regression equation is useful method to obtain the quantity in the regions which tidal currents are dominant.

Determination of Research Octane Number using NIR Spectral Data and Ridge Regression

  • Jeong, Ho Il;Lee, Hye Seon;Jeon, Ji Hyeok
    • Bulletin of the Korean Chemical Society
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    • v.22 no.1
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    • pp.37-42
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    • 2001
  • Ridge regression is compared with multiple linear regression (MLR) for determination of Research Octane Number (RON) when the baseline and signal-to-noise ratio are varied. MLR analysis of near-infrared (NIR) spectroscopic data usually encounters a collinearity problem, which adversely affects long-term prediction performance. The collinearity problem can be eliminated or greatly improved by using ridge regression, which is a biased estimation method. To evaluate the robustness of each calibration, the calibration models developed by both calibration methods were used to predict RONs of gasoline spectra in which the baseline and signal-to-noise ratio were varied. The prediction results of a ridge calibration model showed more stable prediction performance as compared to that of MLR, especially when the spectral baselines were varied. . In conclusion, ridge regression is shown to be a viable method for calibration of RON with the NIR data when only a few wavelengths are available such as hand-carry device using a few diodes.

Predicting a Queue Length Using a Deep Learning Model at Signalized Intersections (딥러닝 모형을 이용한 신호교차로 대기행렬길이 예측)

  • Na, Da-Hyuk;Lee, Sang-Soo;Cho, Keun-Min;Kim, Ho-Yeon
    • The Journal of The Korea Institute of Intelligent Transport Systems
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    • v.20 no.6
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    • pp.26-36
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    • 2021
  • In this study, a deep learning model for predicting the queue length was developed using the information collected from the image detector. Then, a multiple regression analysis model, a statistical technique, was derived and compared using two indices of mean absolute error(MAE) and root mean square error(RMSE). From the results of multiple regression analysis, time, day of the week, occupancy, and bus traffic were found to be statistically significant variables. Occupancy showed the most strong impact on the queue length among the variables. For the optimal deep learning model, 4 hidden layers and 6 lookback were determined, and MAE and RMSE were 6.34 and 8.99. As a result of evaluating the two models, the MAE of the multiple regression model and the deep learning model were 13.65 and 6.44, respectively, and the RMSE were 19.10 and 9.11, respectively. The deep learning model reduced the MAE by 52.8% and the RMSE by 52.3% compared to the multiple regression model.

A Study on the Maneuvering Hydrodynamic Derivatives Estimation Applied the Stern Shape of a Vessel (선미 형상을 반영한 조종 유체력 미계수 추정에 관한 연구)

  • Yoon, Seung-Bae;Kim, Dong-Young;Kim, Sang-Hyun
    • Journal of the Society of Naval Architects of Korea
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    • v.53 no.1
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    • pp.76-83
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    • 2016
  • The various model tests are carried out to estimate and verify a ship performance in the design stage. But in view of the cost, the model test should be applied to every project vessel is very inefficient. Therefore, other methods of predicting the maneuverability with confined data are required at the initial design stage. The purpose of this study is to estimate the hydrodynamic derivatives by using the multiple regression analysis and PMM test data. The characteristics of the stern shape which has an important effect on the maneuverability are applied to the regression analysis in this study. The correlation analysis is performed to select the proper hull form coefficients and stern shape factors used as the variables in the regression analysis. The comparative analysis of estimate results and model test results is conducted on two ships to investigate the effectiveness of the maneuvering hydrodynamic derivatives estimation applied the stern shape. Through the present study, it is verified that the estimation using the stern shape factors as the variables are valid when the stern shape factors are located in the center of the database.

Optimum Model for Analyzing Lifetime Profitability of Holstein Cows

  • Shadparvar, A.A.;Nikbin, S.
    • Asian-Australasian Journal of Animal Sciences
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    • v.21 no.6
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    • pp.769-775
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    • 2008
  • This study was on the relative net income (RNI) for 18,286 Iranian Holstein cows from 799 herds, with first freshening between 1991 and 2000. Two kinds of production system, which differed mainly in milk pricing system and feed cost, were considered. Four different models adopted from the literature were examined to find the optimum model. They differed by the cost of rearing and growth after first calving and they needed different amounts of economic data at the farm level. Results showed that four measures of RNI were highly correlated (>0.96) and could be used equally to measure lifetime profitability of cows. Therefore, in herds without a regular system for recording economic and management data, use of the simplest model is recommended. Multiple regression analysis revealed that RNI was affected by age at first freshening, milk yield and days of productive life (DPL), regardless of production system, and a similar breeding goal could be defined for the two systems. Multiple regression analysis of RNI showed that in order to obtain an unbiased estimate of economic value for DPL, the per day milk yield, not total lifetime milk yield, should be included in the regression model along with DPL. Regression analysis suggested that it is possible to predict RNI using information on age at first freshening along with the length of first lactation and per day milk yield with a coefficient of determination ranging from 0.44 to 0.47.

Optimization of Transonic Airfoil Using GA Based on Neural Network and Multiple Regression Model (유전 알고리듬과 반응표면을 이용한 천음속 익형의 최적설계)

  • Kim, Yun-Sik;Kim, Jong-Hun;Lee, Jong-Soo
    • Transactions of the Korean Society of Mechanical Engineers A
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    • v.26 no.12
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    • pp.2556-2564
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    • 2002
  • The design of airfoil had practiced by repeat tests in its first stage, though an airfoil has as been designed based on simulations according to techniques of computational fluid dynamics. Here, using of traditional optimization is unsuitable because a state of flux is hypersensitive to the shape of airfoil. Therefore the paper optimized the shape of airfoil in transonic region using a genetic algorithm (GA). Response surfaces are based on back propagation neural network (BPN) and regression model. Training data of BPN and regression model were obtained by computational fluid dynamic analysis using CFD-ACE, and each analysis has been designed by design of experiments.

A Study on Addiction Toward Luxury Product (명품 중독(名品 中毒)에 관(關)한 연구(硏究))

  • Lee, Seung-Hee
    • Journal of Fashion Business
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    • v.10 no.4
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    • pp.140-150
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    • 2006
  • The purpose of this study was to examine affecting the addictive buying behavior toward fashion luxury products. 227 female college students were who purchased fashion luxury products surveyed for this study. For data analysis, descriptive statistics, factor analysis, and multiple regression were used. As the results, addictive buying toward luxury products was classified into three factors: impulse addictive, money addictive, and psychological addictive. Also, consumers' individuality pursuit was classified into four factors: unique choice, non-similarity choice, individual choice and non-social interest. Multiple regression results revealed that impulse buying, stress, and unique choice accounted for 38% of the explained variance in addictive buying toward luxury products. Also, regression results indicated that impulse buying, stress, unique choice and reference group accounted for 38% of the explained variance in impulse addictive buying. Finally, regression results pointed out that unique choice and impulse accounted 24% of the explained variance in psychological addictive buying. Based on these results, fashion social responsibility marketing strategies would be suggested.