• 제목/요약/키워드: GLMS

검색결과 11건 처리시간 0.021초

Matrix Formation in Univariate and Multivariate General Linear Models

  • Arwa A. Alkhalaf
    • International Journal of Computer Science & Network Security
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    • 제24권4호
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    • pp.44-50
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    • 2024
  • This paper offers an overview of matrix formation and calculation techniques within the framework of General Linear Models (GLMs). It takes a sequential approach, beginning with a detailed exploration of matrix formation and calculation methods in regression analysis and univariate analysis of variance (ANOVA). Subsequently, it extends the discussion to cover multivariate analysis of variance (MANOVA). The primary objective of this study was to provide a clear and accessible explanation of the underlying matrices that play a crucial role in GLMs. Through linking, essentially different statistical methods, by fundamental principles and algebraic foundations that underpin the GLM estimation. Insights presented here aim to assist researchers, statisticians, and data analysts in enhancing their understanding of GLMs and their practical implementation in diverse research domains. This paper contributes to a better comprehension of the matrix-based techniques that can be extended to GLMs.

Influential Points in GLMs via Backwards Stepping

  • Jeong, Kwang-Mo;Oh, Hae-Young
    • Communications for Statistical Applications and Methods
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    • 제9권1호
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    • pp.197-212
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    • 2002
  • When assessing goodness-of-fit of a model, a small subset of deviating observations can give rise to a significant lack of fit. It is therefore important to identify such observations and to assess their effects on various aspects of analysis. A Cook's distance measure is usually used to detect influential observation. But it sometimes is not fully effective in identifying truly influential set of observations because there may exist masking or swamping effects. In this paper we confine our attention to influential subset In GLMs such as logistic regression models and loglinear models. We modify a backwards stepping algorithm, which was originally suggested for detecting outlying cells in contingency tables, to detect influential observations in GLMs. The algorithm consists of two steps, the identification step and the testing step. In identification step we Identify influential observations based on influencial measures such as Cook's distances. On the other hand in testing step we test the subset of identified observations to be significant or not Finally we explain the proposed method through two types of dataset related to logistic regression model and loglinear model, respectively.

Age Estimation with Panoramic Radiomorphometric Parameters Using Generalized Linear Models

  • Lee, Yeon-Hee;An, Jung-Sub
    • Journal of Oral Medicine and Pain
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    • 제46권2호
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    • pp.21-32
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    • 2021
  • Purpose: The purpose of the present study was to investigate the correlation between age and 34 radiomorphometric parameters on panoramic radiographs, and to provide generalized linear models (GLMs) as a non-invasive, inexpensive, and accurate method to the forensic judgement of living individual's age. Methods: The study included 417 digital panoramic radiographs of Korean individuals (178 males and 239 females, mean age: 32.57±17.81 years). Considering the skeletal differences between the sexes, GLMs were obtained separately according to sex, as well as across the total sample. For statistical analysis and to predict the accuracy of the new GLMs, root mean squared error (RMSE) and adjusted R-squared (R2) were calculated. Results: The adjusted R2-values of the developed GLMs in the total sample, and male and female groups were 0.623, 0.637, and 0.660, respectively (p<0.001), while the allowable RMSE values were 8.80, 8.42, and 8.53 years, respectively. In the GLM of the total sample, the most influential predictor of greater age was decreased pulp area in the #36 first molar (beta=-26.52; p<0.01), followed by the presence of periodontitis (beta=10.24; p<0.01). In males, the most influential factor was the presence of periodontitis (beta=9.20; p<0.05), followed by the number of full veneer crowns (beta=2.19; p<0.001). In females, the most influential predictor was the presence of periodontitis (beta=18.10; p<0.001), followed by the tooth area of the #16 first molar (beta=-11.57; p<0.001). Conclusions: We established acceptable GLM for each sex and found out the predictors necessary to age estimation which can be easily found in panoramic radiographs. Our study provides reference that parameters such as the area of tooth and pulp, the number of teeth treated, and the presence of periodontitis should be considered in estimating age.

정부지출과 소비지출에 의한 소득주도성장 경로 분석 (Analysis of Income-led Growth Path Induced by Government and Consumption Expenditures)

  • 이현재
    • 한국콘텐츠학회논문지
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    • 제20권7호
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    • pp.602-617
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    • 2020
  • 자유시장 경제를 근간으로 한 이윤주도 성장전략의 대안으로 논의되고 있는 소득주도성장 전략은 정부 부문의 적극적인 개입이 필요하므로 정부지출의 효용성이 중요한 요인으로 인식되고 있다. 본 논문에서는 지난 수십 년 동안 분배체계에 의한 소득주도성장 정책을 수행해 온 북유럽과 남미 국가, 그리고 한국을 대상으로 정부지출과 소비지출의 경제적 관계를 규명하고, 이 결과를 바탕으로 소득주도성장 경로를 논의하였다. 지출 국민소득에 의한 구조방정식을 설정하고 일반화된 선형모형(GLMs)에 의해 추정한 실증분석 결과에 의하면, 북유럽 국가와 한국의 경우 정책적 효과가 크지는 않지만, 소득주도성장 정책으로 국민소득을 증가시킬 수 있는 것으로 나타났다. 그러나 남미 국가는 소득주도성장 정책의 운용이 불안정할 뿐만 아니라 정책효과도 나타나지 않는 것으로 분석되었다. 또한, 소득주도성장 정책을 수행하는 과정에서 저소비 계층보다는 중간소비 계층을 활용한 경로가 더욱 효율적인 것으로 나타났다. 결과적으로 소득주도성장 정책은 지속 가능한 성장 전략이라기보다는 보완적 기능을 수행하는 정책으로 활용하는 것이 바람직할 것이다.

Development and Validation of Generalized Linear Regression Models to Predict Vessel Enhancement on Coronary CT Angiography

  • Masuda, Takanori;Nakaura, Takeshi;Funama, Yoshinori;Sato, Tomoyasu;Higaki, Toru;Kiguchi, Masao;Matsumoto, Yoriaki;Yamashita, Yukari;Imada, Naoyuki;Awai, Kazuo
    • Korean Journal of Radiology
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    • 제19권6호
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    • pp.1021-1030
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    • 2018
  • Objective: We evaluated the effect of various patient characteristics and time-density curve (TDC)-factors on the test bolus-affected vessel enhancement on coronary computed tomography angiography (CCTA). We also assessed the value of generalized linear regression models (GLMs) for predicting enhancement on CCTA. Materials and Methods: We performed univariate and multivariate regression analysis to evaluate the effect of patient characteristics and to compare contrast enhancement per gram of iodine on test bolus (${\Delta}HUTEST$) and CCTA (${\Delta}HUCCTA$). We developed GLMs to predict ${\Delta}HUCCTA$. GLMs including independent variables were validated with 6-fold cross-validation using the correlation coefficient and Bland-Altman analysis. Results: In multivariate analysis, only total body weight (TBW) and ${\Delta}HUTEST$ maintained their independent predictive value (p < 0.001). In validation analysis, the highest correlation coefficient between ${\Delta}HUCCTA$ and the prediction values was seen in the GLM (r = 0.75), followed by TDC (r = 0.69) and TBW (r = 0.62). The lowest Bland-Altman limit of agreement was observed with GLM-3 (mean difference, $-0.0{\pm}5.1$ Hounsfield units/grams of iodine [HU/gI]; 95% confidence interval [CI], -10.1, 10.1), followed by ${\Delta}HUCCTA$ ($-0.0{\pm}5.9HU/gI$; 95% CI, -11.9, 11.9) and TBW ($1.1{\pm}6.2HU/gI$; 95% CI, -11.2, 13.4). Conclusion: We demonstrated that the patient's TBW and ${\Delta}HUTEST$ significantly affected contrast enhancement on CCTA images and that the combined use of clinical information and test bolus results is useful for predicting aortic enhancement.

Cumulative Sums of Residuals in GLMM and Its Implementation

  • Choi, DoYeon;Jeong, KwangMo
    • Communications for Statistical Applications and Methods
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    • 제21권5호
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    • pp.423-433
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    • 2014
  • Test statistics using cumulative sums of residuals have been widely used in various regression models including generalized linear models(GLM). Recently, Pan and Lin (2005) extended this testing procedure to the generalized linear mixed models(GLMM) having random effects, in which we encounter difficulties in computing the marginal likelihood that is expressed as an integral of random effects distribution. The Gaussian quadrature algorithm is commonly used to approximate the marginal likelihood. Many commercial statistical packages provide an option to apply this type of goodness-of-fit test in GLMs but available programs are very rare for GLMMs. We suggest a computational algorithm to implement the testing procedure in GLMMs by a freely accessible R package, and also illustrate through practical examples.

Modeling Approaches for Dynamic Robust Design Experiment

  • Bae, Suk-Joo
    • 한국경영과학회:학술대회논문집
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    • 한국경영과학회 2006년도 추계학술대회
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    • pp.373-376
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    • 2006
  • In general, there are three kinds of methods in analyzing dynamic robust design experiment: loss model approach, response function approach, and response model approach. In this talk, we review the three modeling approaches in terms of several criteria in comparison. This talk also generalizes the response model approach based on a generalized linear model. We develop a generalized two-step optimization procedure to substantially reduce the process variance by dampening the effect of both explicit and hidden noise variables. The proposed method provides more reliable results through iterative modeling of the residuals from the fitted response model. The method is compared with three existing approaches in practical examples.

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FSAL MONO-IMPLICIT NORDSIECK GENERAL LINEAR METHODS WITH INHERENT RUNGE-KUTTA STABILITY FOR DAES

  • OLATUNJI, P.O.;IKHILE, M.N.O.
    • Journal of the Korean Society for Industrial and Applied Mathematics
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    • 제25권4호
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    • pp.262-295
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    • 2021
  • This paper introduces mono-implicit general linear methods, a special class of general linear methods, which are implicit in the output solution for the numerical integration of differential algebraic equations. We show how L-stable inherent Runge-Kutta members can be derived. The procedures for implementation have been discussed. The numerical test on the problem considered shows that the methods have improved accuracy when compared to RADAU IIA and the results from MATLAB ode15s, which have been taken as our reference solution.

다랑어 연승어업에서 눈다랑어 어획률에 미치는 낚시 및 미끼의 효과 (Effects of Hook and Bait Types on Bigeye Tuna Catch Rates in the Tuna Longline Fishery)

  • 김순송;문대연;안두해;황선재;김영승
    • 한국어류학회지
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    • 제20권2호
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    • pp.105-111
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    • 2008
  • 다랑어낚시 및 사용미끼에 따른 어획률을 비교하기 위해, 2006년 9~10월간 태평양 중동부 해역에서 다랑어연승 시험조사가 수행되었다. 일반선형모형(GLM)을 이용하여 재래식 다랑어낚시 1종(J4)와 환형낚시 3종(C15, C16, C18), 미끼 5종(고등어(CM), 전갱이(JM), 밀크피쉬(MF), 정어리(SD), 오징어(SQ)) 및 낚시심도를 나타내는 낚시 순번들이 눈다랑어 어획률(1,000낚시당 마리수)에 미치는 효과를 평가하였다. 총 28회 조업에서 낚시순번 간 눈다랑어 어획률에는 유의한 차이가 인정되었다. GLM분석에서 낚시순번에 의한 눈다랑어 어획률 편차는 33%로 나타났다. 미끼 종류 간 어획률 차이는 그 편차가 2.7%로 적게 나타났고, 낚시형 4종 간 그 차이는 매우 적어 유의하지 않게 나타났다. 따라서, 낚시형 및 미끼 종류의 선택은 다랑어 연승어업에서 눈다랑어 어획률 차이에 영향을 주지 않는 것으로 평가되었으나, 어획수심을 나타내는 낚시순번은 눈다랑어 어획률에 영향을 주는 요인으로 판단되었다.

사용자의 지속적이며 자발적인 참여를 위한 게임화 기반의 콘텐츠 관리 시스템 설계 (Gamified Contents Management System design for continuous and voluntary participation of Users)

  • 최원겸;윤찬;우탁
    • 한국게임학회 논문지
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    • 제18권6호
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    • pp.5-16
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    • 2018
  • 콘텐츠에서 자발적인 사용자 참여를 유도하고 유지하는 것은 매우 어렵지만 중요한 일이다. 그 예로 많은 인터넷 콘텐츠 등에서 사용자들의 참여와 그 유지를 위해 금전적 보상을 제공하고 있다. 그러나 금전적 보상처럼 외재적 동기만을 자극하는 등의 방식으로는 한계가 있으며, 콘텐츠의 대한 지속적이고 자발적인 사용자 참여를 얻기 위해서는 정교한 설계와 관리가 필요하다. 이를 위해, Gamified Learning Management System의 예를 참고하여, 기존의 Contents Management System(CMS)을 확장한 게임화 기반의 CMS(Gamified CMS)를 제안하고자 한다. 이를 통해 궁극적으로 사용자의 콘텐츠에 대한 참여와 몰입을 증대시키고자 한다.