Although logistic regression is the most popular for modelling regression relationships with binary responses,many find relative risk(RR),or risk ratio,easier to interpret and prefer to use this measure of risk in reg...Although logistic regression is the most popular for modelling regression relationships with binary responses,many find relative risk(RR),or risk ratio,easier to interpret and prefer to use this measure of risk in regression analysis.Indeed,since Zou published his modified Poisson regression approach for modelling RR for cross-sectional data,his paper has been cited over 7000 times,demonstrating the popularity of this alternative measure of risk in regression analysis involving binary responses.As longitudinal studies have become increasingly popular in clinical trials and observational studies,it is imperative to extend Zou’s approach for longitudinal data.The two most popular approaches for longitudinal data analysis are the generalised linear mixed-effects model(GLMM)and generalised estimating equations(GEE).However,the parametric GLMM cannot be used for the extension within the current context,because Zou’s approach treats the binary response as a Poisson variable,which is at odds with the Bernoulli distribution for the binary response.On the other hand,as it imposes no mathematical model on data distributions,the semiparametric GEE is coherent with Zou’s modified Poisson regression.In this paper,we develop a GEE-based longitudinal model for binary responses to provide inference about RR.展开更多
In order to figure out the redox conditions and paleo-sedimentary environment of the Middle Devonian shales in the northwest of Guizhong Depression,the trace element analysis was conducted on the Middle Devonian cores...In order to figure out the redox conditions and paleo-sedimentary environment of the Middle Devonian shales in the northwest of Guizhong Depression,the trace element analysis was conducted on the Middle Devonian cores(320.35–938.50 m)of the typical shale gas investigation well(GY-1)at a 1.50 m sampling interval through X-ray fluorescence spectroscopy(XRF)and inductively coupled plasma mass spectrometry(ICP-MS).According to the test result,the average values of V/(V+Ni),V/Cr and Ni/Co in Nabiao formation(Fm.)are larger than 0.67,4.65 and 7.71 respectively,and Nabiao Fm.is rich in biological assemblages such as tabasheer,ammonite,etc.These evidences indicate the rising sea level rose relatively in the sedimentation period of Nabiao Fm.and a deepwater shelf environment,which was favorable for the preservation of organic matters.The V/(V+Ni),V/Cr and Ni/Co in Luofu Fm.and Tangting Fm.are 0.38–0.65,0.73–4.10 and 3.70–6.72 respectively,indicating that the sea level dropped relatively in their sedimentation period,during which the water bodies became shallow,and the sedimentary environment was a weak oxidizing shallow water shelf environment.In addition,the variation of TOC has a high correlation with the enrichment degree of Ba element,indicating the favorable conditions for the enrichment and preservation of organic matters under an oxygen-deficient environment.Moreover,according to the identification of trace element indexes,the northwest of Guizhong Depression experienced the sedimentary cycle of relative rise to relative fall of sea level from bottom to top in the Middle Devonian sedimentation period.The relative sea level rose to the highest in the sedimentation period of Nabiao Fm.,in which the organic-rich shales with stable thickness and high organic content were deposited.Hence,the Nabiao Fm.could be regarded as the favorable exploration target interval in this area.展开更多
基金supported by the National Institutes of Health(grant UL1TR001442)of Georgia Clinical and Translational Science Alliance funding.
文摘Although logistic regression is the most popular for modelling regression relationships with binary responses,many find relative risk(RR),or risk ratio,easier to interpret and prefer to use this measure of risk in regression analysis.Indeed,since Zou published his modified Poisson regression approach for modelling RR for cross-sectional data,his paper has been cited over 7000 times,demonstrating the popularity of this alternative measure of risk in regression analysis involving binary responses.As longitudinal studies have become increasingly popular in clinical trials and observational studies,it is imperative to extend Zou’s approach for longitudinal data.The two most popular approaches for longitudinal data analysis are the generalised linear mixed-effects model(GLMM)and generalised estimating equations(GEE).However,the parametric GLMM cannot be used for the extension within the current context,because Zou’s approach treats the binary response as a Poisson variable,which is at odds with the Bernoulli distribution for the binary response.On the other hand,as it imposes no mathematical model on data distributions,the semiparametric GEE is coherent with Zou’s modified Poisson regression.In this paper,we develop a GEE-based longitudinal model for binary responses to provide inference about RR.
基金This article was supported by project of China Geological Survey“Guizhong-Nanpanjiang Depression shale gas geological survey”(DD20190088).
文摘In order to figure out the redox conditions and paleo-sedimentary environment of the Middle Devonian shales in the northwest of Guizhong Depression,the trace element analysis was conducted on the Middle Devonian cores(320.35–938.50 m)of the typical shale gas investigation well(GY-1)at a 1.50 m sampling interval through X-ray fluorescence spectroscopy(XRF)and inductively coupled plasma mass spectrometry(ICP-MS).According to the test result,the average values of V/(V+Ni),V/Cr and Ni/Co in Nabiao formation(Fm.)are larger than 0.67,4.65 and 7.71 respectively,and Nabiao Fm.is rich in biological assemblages such as tabasheer,ammonite,etc.These evidences indicate the rising sea level rose relatively in the sedimentation period of Nabiao Fm.and a deepwater shelf environment,which was favorable for the preservation of organic matters.The V/(V+Ni),V/Cr and Ni/Co in Luofu Fm.and Tangting Fm.are 0.38–0.65,0.73–4.10 and 3.70–6.72 respectively,indicating that the sea level dropped relatively in their sedimentation period,during which the water bodies became shallow,and the sedimentary environment was a weak oxidizing shallow water shelf environment.In addition,the variation of TOC has a high correlation with the enrichment degree of Ba element,indicating the favorable conditions for the enrichment and preservation of organic matters under an oxygen-deficient environment.Moreover,according to the identification of trace element indexes,the northwest of Guizhong Depression experienced the sedimentary cycle of relative rise to relative fall of sea level from bottom to top in the Middle Devonian sedimentation period.The relative sea level rose to the highest in the sedimentation period of Nabiao Fm.,in which the organic-rich shales with stable thickness and high organic content were deposited.Hence,the Nabiao Fm.could be regarded as the favorable exploration target interval in this area.
