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2022

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Has Winter Weather In Southwest Ohio Been Affected By The El Niño Southern Oscillation, The North Atlantic Oscillation, The Pacific Decadal Oscillation, And The Atlantic Multidecadal Oscillation?, John A. Blue Jan 2022

Has Winter Weather In Southwest Ohio Been Affected By The El Niño Southern Oscillation, The North Atlantic Oscillation, The Pacific Decadal Oscillation, And The Atlantic Multidecadal Oscillation?, John A. Blue

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Winter temperature and precipitation in Southwest Ohio over the last century were examined for anomalies attributable to teleconnections with large-scale atmospheric perturbations caused by the El Niño Southern Oscillation (ENSO), the North Atlantic Oscillation (NAO), the Pacific Decadal Oscillation (PDO), and the Atlantic Multidecadal Oscillation (AMO). The record of temperature gives evidence of a teleconnection with the NAO, ENSO, and PDO, with the strongest link being for phases of the NAO. Most winters during positive NAO phases had mean monthly temperature warmer than the century long mean, and the majority of negative NAO phase winters had colder temperatures. The difference …


Mixed-Effects Regression Models For Analyzing Data With Excess Zeros, Guangyu Xu Jan 2022

Mixed-Effects Regression Models For Analyzing Data With Excess Zeros, Guangyu Xu

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Data with excess zeros are common in many applications. Failure to account for the extra zeros may lead to biased estimates and misleading inference when analyzing this data type. To investigate the association between a set of predictor variables and an outcome variable with excess zeros, two kinds of regression models, the hurdle model and the zero-inflated model, are commonly used. In these models, the traditional tests, such as the likelihood-ratio test and the Wald test, can only be used to detect the fixed effects in association analysis. Recently, several random-effects or mixed-effects tests have been proposed for association analysis, …