• Title/Summary/Keyword: Goodness-of-Fit

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Differences by Selection Method for Exposure Factor Input Distribution for Use in Probabilistic Consumer Exposure Assessment

  • Kang, Sohyun;Kim, Jinho;Lim, Miyoung;Lee, Kiyoung
    • Journal of Environmental Health Sciences
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    • v.48 no.5
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    • pp.266-271
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    • 2022
  • Background: The selection of distributions of input parameters is an important component in probabilistic exposure assessment. Goodness-of-fit (GOF) methods are used to determine the distribution of exposure factors. However, there are no clear guidelines for choosing an appropriate GOF method. Objectives: The outcomes of probabilistic consumer exposure assessment were compared by using five different GOF methods for the selection of input distributions: chi-squared test, Kolmogorov-Smirnov test (K-S), Anderson-Darling test (A-D), Akaike information criterion (AIC) and Bayesian information criterion (BIC). Methods: Individual exposures were estimated based on product usage factor combinations from 10,000 respondents. The distribution of individual exposure was considered as the true value of population exposures. Results: Among the five GOF methods, probabilistic exposure distributions using the A-D and K-S methods were similar to individual exposure estimations. Comparing the 95th percentiles of the probabilistic distributions and the individual estimations for 10 CPs, there were 0.73 to 1.92 times differences for the A-D method, and 0.73 to 1.60 times differences (excluding tire-shine spray) for the K-S method. Conclusions: There were significant differences in exposure assessment results among the selection of the GOF methods. Therefore, the GOF methods for probabilistic consumer exposure assessment should be carefully selected.

A Sequential Analysis of Mother-Infant Interaction (연속적 분석법을 통한 어머니와 유아의 상호작용 연구)

  • Choae, Jin Kyong
    • Korean Journal of Child Studies
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    • v.6 no.1
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    • pp.3-16
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    • 1985
  • The purpose of this study was the application of sequential analysis to mother-infant interaction data, with particular reference to goodness of fit. The subjects of this study were 22 7- to 16-month-old infants(12 girls and 10 boys) and their mothers. Each mother-infant dyad was videotaped in a 5-min free-play session in the playroom. The videotaped data was transcribed on the behavioral checklist every 3 seconds. The recorded raw data were lagged by one time interval (3 sec.). Transitional probabilities from behavior at time t-1 to behavior at time t were gathered. The statistical analysis of frequency data and transitional probabilities consisted of Z test, t test, and sign test. It was found that regarding 1) direction of effect: the transitional probability of infant vocalization following maternal vocalization was significantly higher than the reverse; the transitional probability of a 'Coacting State' following a 'Mother Active State' was significantly higher than the reverse; the probability of a 'Mother Active State' following 'Quiescent State' was significantly higher than that of a 'Coacting State' following an 'Infant Active State'; 2) sex differences: male infants' transitional probability from an 'Infant Active State' to a 'Quiescent State' was significantly higher than that of female infants; 3) age differences: more than younger infants older infants had higher transitional probabilities from a 'Mother Active State' to a 'Coacting State', from a 'Parallel State' to a 'Coacting State', and from a 'Quiescent State' to a 'Parallel State'. These showed goodness of fit for sex and age differences, particularily for direction of effect.

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A Structural Relationship among Emotional Leadership of Educational Administrative Officials' Superiors, Empowerment, and Job Satisfaction (교육행정공무원 상급자의 감성리더십, 임파워먼트, 직무만족 간의 구조 관계)

  • LEE, Ki-Yong
    • Journal of Fisheries and Marine Sciences Education
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    • v.28 no.4
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    • pp.936-946
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    • 2016
  • The purpose of this study is to examine structural relations between the emotional leadership of educational administrative officials' superiors and subordinates' empowerment and job satisfaction. To attain the study goal, this researcher finally selected 368 educational administrative officials working in Gyeongsangbuk-do and conducted statistical analysis. Accordingly, this study has drawn the following detailed conclusions: First, there is statistically significant positive correlation among the subfactors of the emotional leadership of educational administrative officials' superiors and subordinates' empowerment and job satisfaction. Second, it has been found that the hypothetical path model to explain the emotional leadership of educational administrative officials' superiors and subordinates' empowerment and job satisfaction is appropriate. In other words, among the goodness-of-fit indexes of the final study model, ${\chi}^2=203.657$ (p<.001), RMR equals .030, RMSEA is .093, GFI equals .910, and AGFI is .900. About its relative goodness-of-fit indexes, TLI equals .930, NFI is .933, CFI equals .948, and IFI is .949; therefore, all indexes have been found to be allowable. Third, emotional leadership of educational administrative officials' superiors have had this influence directly on job satisfaction. But, the total influence of the emotional leadership of educational administrative officials' superiors on job satisfaction is smaller than that on job satisfaction with the mediation of subordinates' empowerment.

Channel Capacity Analysis for Indoor PLC Networks with Considering the Effect of Loading conditions of Networks on Channel State Information (네트워크 부하 조건의 변화가 채널 상태 정보에 미치는 영향을 고려한 옥내 전력선 통신 채널의 채널 용량 분석)

  • Shin, Jae-Young;Jeong, Ji-Chai
    • The Transactions of The Korean Institute of Electrical Engineers
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    • v.60 no.2
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    • pp.252-256
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    • 2011
  • We analyze the channel capacity with considering the effect of the loading conditions of indoor PLC networks on channel state information. We consider various numbers of load for two kinds of the networks with regular length branches and a deployed network of indoor PLC. For calculating the channel capacity degradation, two noise scenarios and impedances are considered. From the simulation results, we suggest the robust regression lines for modeling the channel capacity degradation. In the cases of 0 $\Omega$ and $Z_0$ loads, natural log and linear function curve show the best goodness of fit, respectively. For the deployed indoor PLC network with 0 $\Omega$ loads, compared with the networks with regular length branches, the goodness of fit decreases by the amount of 0.12 and 0.15 for low noise and high noise scenarios, respectively. Using the regression lines, we can estimate the channel capacity degradation without measurement.

Probabilistic analysis of spectral displacement by NSA and NDA

  • Devandiran, P.;Kamatchi, P.;Rao, K. Balaji;Ravisankar, K.;Iyer, Nagesh R.
    • Earthquakes and Structures
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    • v.5 no.4
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    • pp.439-459
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    • 2013
  • Main objective of the present study is to determine the statistical properties and suitable probability distribution functions of spectral displacements from nonlinear static and nonlinear dynamic analysis within the frame work of Monte Carlo simulation for typical low rise and high rise RC framed buildings located in zone III and zone V and designed as per Indian seismic codes. Probabilistic analysis of spectral displacement is useful for strength assessment and loss estimation. To the author's knowledge, no study is reported in literature on comparison of spectral displacement including the uncertainties in capacity and demand in Indian context. In the present study, uncertainties in capacity of the building is modeled by choosing cross sectional dimensions of beams and columns, density and compressive strength of concrete, yield strength and elastic modulus of steel and, live load as random variables. Uncertainty in demand is modeled by choosing peak ground acceleration (PGA) as a random variable. Nonlinear static analysis (NSA) and nonlinear dynamic analysis (NDA) are carried out for typical low rise and high rise reinforced concrete framed buildings using IDARC 2D computer program with the random sample input parameters. Statistical properties are obtained for spectral displacements corresponding to performance point from NSA and maximum absolute roof displacement from NDA and suitable probability distribution functions viz., normal, Weibull, lognormal are examined for goodness-of-fit. From the hypothesis test for goodness-of-fit, lognormal function is found to be suitable to represent the statistical variation of spectral displacement obtained from NSA and NDA.

Negative Exponential Disparity Based Deviance and Goodness-of-fit Tests for Continuous Models: Distributions, Efficiency and Robustness

  • Jeong, Dong-Bin;Sahadeb Sarkar
    • Journal of the Korean Statistical Society
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    • v.30 no.1
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    • pp.41-61
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    • 2001
  • The minimum negative exponential disparity estimator(MNEDE), introduced by Lindsay(1994), is an excellenet competitor to the minimum Hellinger distance estimator(Beran 1977) as a robust and yet efficient alternative to the maximum likelihood estimator in parametric models. In this paper we define the negative exponential deviance test(NEDT) as an analog of the likelihood ratio test(LRT), and show that the NEDT is asymptotically equivalent to he LRT at the model and under a sequence of contiguous alternatives. We establish that the asymptotic strong breakdown point for a class of minimum disparity estimators, containing the MNEDE, is at least 1/2 in continuous models. This result leads us to anticipate robustness of the NEDT under data contamination, and we demonstrate it empirically. In fact, in the simulation settings considered here the empirical level of the NEDT show more stability than the Hellinger deviance test(Simpson 1989). The NEDT is illustrated through an example data set. We also define a goodness-of-fit statistic to assess adequacy of a specified parametric model, and establish its asymptotic normality under the null hypothesis.

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Noisy Speech Enhancement Based on Complex Laplacian Probability Density Function (복소 라플라시안 확률 밀도 함수에 기반한 음성 향상 기법)

  • Park, Yun-Sik;Jo, Q-Haing;Chang, Joon-Hyuk
    • Journal of the Institute of Electronics Engineers of Korea SP
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    • v.44 no.6
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    • pp.111-117
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    • 2007
  • This paper presents a novel approach to speech enhancement based on a complex Laplacian probability density function (pdf). With a use of goodness-of-fit (GOF) test we show that the complex Laplacian pdf is more suitable to describe the conventional Gaussian pdf. The likelihood ratio (LR) is applied to derive the speech absence probability in the speech enhancement algorithm. The performance of the proposed algorithm is evaluated by the objective test and yields better results compared with the conventional Gaussian pdf-based scheme.

Regression Diagnostics on Joint Modelling of Mean and Dispersion (평균과 분산의 동시모형에 따른 회귀진단법에 관한 연구)

  • 강위창;이영조;송문섭
    • The Korean Journal of Applied Statistics
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    • v.13 no.2
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    • pp.407-414
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    • 2000
  • Carroll and Ruppert(1988) analyzed the esterase assay data with regression model based on quasi-likelihood. Jung and Lee(1997) introduced a goodness-of-fit test for testing the adequacy of the quasi-likelihood and claimed that there is no gross inadequacy with the model because their test was not rejected. However, Lee and Xelder(199S)'s residual plots revealed that the model did not sufficiently reflect the increase of the variance with that of the mean. In this paper, we re-analyze the esterase assay data with the joint modelling of mean and dispersion in Lee and l\elder(1998) and evaluate the validity of the fitted model by applying the residual plots. And it is illustrated that Lee and Nelder(199S)'s restricted likelihood is more efficient in goodness-of-fit test for the dispersion model.

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A Development of Optimal Design Model for Initial Blank Shape Using Artificial Neural Network in Rectangular Case Forming with Large Aspect Ratio (세장비가 큰 사각케이스 성형 공정에서의 인공신경망을 적용한 초기 블랭크 형상 최적설계 모델 개발)

  • Kwak, M.J.;Park, J.W.;Park, K.T.;Kang, B.S.
    • Transactions of Materials Processing
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    • v.29 no.5
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    • pp.272-281
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    • 2020
  • As the thickness of mobile communication devices is getting thinner, the size of the internal parts is also getting smaller. Among them, the battery case requires a high-level deep drawing technique because it has a rectangular shape with a large aspect ratio. In this study, the initial blank shape was optimized to minimize earing in a multi-stage deep drawing process using an artificial neural network(ANN). There has been no reported case of applying artificial neural network technology to the initial blank optimal design for a square case with large aspect ratio. The training data for ANN were obtained though simulation, and the model reliability was verified by performing comparative study with regression model using random sample test and goodness-of-fit test. Finally, the optimal design of the initial blank shape was performed through the verified ANN model.

A Nested Logit Model of Auto Ownership and Vehicle Type Choices (승용차 보유대수와 차종선택에 대한 네스티드로짓모형의 추정)

  • Park, Sang-Jun;Kim, Seong-Su
    • Journal of Korean Society of Transportation
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    • v.25 no.1 s.94
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    • pp.133-141
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    • 2007
  • The study examines households' auto ownership and car type choice with a nested legit model. In summary. ${\rho}^2$ and the inclusive values, which represent the goodness of fit of the model, are statistically significant. Therefore. the nested logit model is superior to the standard legit model in this case. Also. the elasticity of operating costs is larger than 1, which means households' car ownership and car type choice is very sensitive to the operating costs. Finally, the elasticity of the operating costs in the lower income group is higher than that or the operating costs in the higher income group.