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Longitudinal Data Analysis and Time Series Commons

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Toward Using High-Frequency Coastal Radars For Calibration Of S-Ais Based Ocean Vessel Tracking Models, Ben Freidrich 2019 Wilfrid Laurier University

Toward Using High-Frequency Coastal Radars For Calibration Of S-Ais Based Ocean Vessel Tracking Models, Ben Freidrich

Theses and Dissertations (Comprehensive)

Most of the world relies on ships for transportation, shipping, and tourism. Automatic Identification System messages are transmitted from ships and provide a wealth of positional data on these open ocean vessels. This data is being utilized to determine the optimal path for ships, as well as predicting where a ship may be going in the near future. It has only been in the past decade that Automatic Identification Systems (AIS) signals have been easily received with satellites (S-AIS) so there have been few studies that look at using available information and pairing it with the new abundance of ship ...


Model Misspecification And Assumption Violations With The Linear Mixed Model: A Meta-Analysis, Brandon LeBeau, Yoon Ah Song, Wei Cheng Liu 2018 University of Iowa

Model Misspecification And Assumption Violations With The Linear Mixed Model: A Meta-Analysis, Brandon Lebeau, Yoon Ah Song, Wei Cheng Liu

Department of Psychological and Quantitative Foundations Publications

This meta analysis attempts to synthesize the Monte Carlo literature for the linear mixed model under a longitudinal framework. The empirical type I error rate will serve as the effect size and Monte Carlo simulation conditions will be coded to serve as moderator variables. The type I error rate for the fixed and random effects will be explored as the primary dependent variable. Effect sizes were coded from 13 studies, resulting in a total of 4,002 and 621 effect sizes for fixed and random effects. Meta-regression and proportional odds models were used to explore variation in the empirical type ...


Instances Of Influenza In The United States Visualized, Parth Patel 2018 CUNY New York City College of Technology

Instances Of Influenza In The United States Visualized, Parth Patel

Publications and Research

The Tycho Project collects large data sets related to healthcare and in particular, instances and geographical information of diseases. We look at the instance counts and locations of Influenza from 1919-1951 across the United States. We hope to find seasonal and geographical insight to the spread of the disease.


Role Of Misclassification Estimates In Estimating Disease Prevalence And A Non-Linear Approach To Study Synchrony Using Heart Rate Variability In Chickens, Dola Pathak 2018 University of Nebraska-Lincoln

Role Of Misclassification Estimates In Estimating Disease Prevalence And A Non-Linear Approach To Study Synchrony Using Heart Rate Variability In Chickens, Dola Pathak

Dissertations and Theses in Statistics

Infectious disease assays can be imperfect. When estimating disease prevalence, these imperfections are accounted for by incorporating assay sensitivity and specificity into point and variance estimates. Unfortunately, these accuracy measures are often treated as fixed constants, rather than acknowledging that they are estimates from an assay validation process. The purpose of this study is to show the detrimental effect of not taking into account this sampling variability when samples are obtained through group testing (aka, pooled testing). We show that confidence interval coverage can dramatically decline as the sample size increases for the main sample of interest. As a remedy ...


Snakebite Dynamics Of Colombia: Effects Of Precipitation Seasonality Of Incidence, Carlos Cruz 2018 Illinois State University

Snakebite Dynamics Of Colombia: Effects Of Precipitation Seasonality Of Incidence, Carlos Cruz

Annual Symposium on Biomathematics and Ecology: Education and Research

No abstract provided.


Monitoring And Evaluating The Influences Of Class V Injection Wells On Urban Karst Hydrology, James Adam Shelley 2018 Western Kentucky University

Monitoring And Evaluating The Influences Of Class V Injection Wells On Urban Karst Hydrology, James Adam Shelley

Masters Theses & Specialist Projects

The response of a karst aquifer to storm events is often faster and more severe than that of a non-karst aquifer. This distinction is often problematic for planners and municipalities, because karst flooding does not typically occur along perennial water courses; thus, traditional flood management strategies are usually ineffective. The City of Bowling Green (CoBG), Kentucky is a representative example of an area plagued by karst flooding. The CoBG, is an urban karst area (UKA), that uses Class V Injection Wells to lessen the severity of flooding. The overall effectiveness, siting, and flooding impact of Injection Wells in UKA’s ...


Identifying Treatment Effects In The Presence Of Confounded Types, Desire Kedagni 2018 Iowa State University

Identifying Treatment Effects In The Presence Of Confounded Types, Desire Kedagni

Economics Working Papers

In this paper, I consider identification of treatment effects when
the treatment is endogenous. The use of instrumental variables is a popular
solution to deal with endogeneity, but this may give misleading answers when
the instrument is invalid. I show that when the instrument is invalid due to
correlation with the first stage unobserved heterogeneity, a second (also
possibly invalid) instrument allows to partially identify not only the local
average treatment effect but also the entire potential outcomes distributions
for compliers. I exploit the fact that the distribution of the observed
outcome in each group defined by the treatment and ...


Basic Psychological Need Satisfaction Toward Learning: A Longitudinal Test Of Mediation Using Bifactor Exploratory Structural Equation Modeling [Accepted Manuscript], Alex C. Garn, Alexandre J.S. Morin, Chris Lonsdale 2018 Australian Catholic University

Basic Psychological Need Satisfaction Toward Learning: A Longitudinal Test Of Mediation Using Bifactor Exploratory Structural Equation Modeling [Accepted Manuscript], Alex C. Garn, Alexandre J.S. Morin, Chris Lonsdale

Faculty of Health Sciences Publications

Student motivation research seeks to uncover greater understanding of when, how, and why students succeed or fail in school settings. Self-determination theory has been at the forefront of helping educational stakeholders answer questions on student motivation. This study investigates the motivation mediation model proposed by self-determination theory using a longitudinal research design. A total of 1,789 Grade 8 Australian physical education students reported their perceptions of their teacher's motivational style (antecedent), their levels of basic psychological need satisfaction(mediator), their motivation (outcome), and their affect (outcome) across 3 time points. Bifactor exploratory structural equation modeling (bifactor-ESEM) was used ...


Inversion Copulas From Nonlinear State Space Models With An Application To Inflation Forecasting, Michael S. Smith, Worapree Ole Maneesoonthorn 2018 Melbourne Business School

Inversion Copulas From Nonlinear State Space Models With An Application To Inflation Forecasting, Michael S. Smith, Worapree Ole Maneesoonthorn

Michael Stanley Smith

We propose the construction of copulas through the inversion of nonlinear state space models. These copulas allow for new time series models that have the same serial dependence structure as a state space model, but with an arbitrary marginal distribution, and flexible density forecasts. We examine the time series properties of the copulas, outline serial dependence measures, and estimate the models using likelihood-based methods. Copulas constructed from three example state space models are considered: a stochastic volatility model with an unobserved component, a Markov switching autoregression, and a Gaussian linear unobserved component model. We show that all three inversion copulas ...


Spatio-Temporal Dynamics Of Atlantic Cod Bycatch In The Maine Lobster Fishery And Its Impacts On Stock Assessment, Robert E. Boenish 2018 University of Maine

Spatio-Temporal Dynamics Of Atlantic Cod Bycatch In The Maine Lobster Fishery And Its Impacts On Stock Assessment, Robert E. Boenish

Electronic Theses and Dissertations

Of the most iconic fish species in the world, the Atlantic cod (Gadus morhua, hereafter, cod) has been a mainstay in the North Atlantic for centuries. While many global fish stocks have received increased pressure with the advent of new, more efficient fishing technology in the mid-20th century, exceptional pressure has been placed on this prized gadoid. Bycatch, or the unintended catch of organisms, is one of the biggest global fisheries issues. Directly resulting from the failed recovery of cod in the GoM, attention has been placed as to possible sources of unaccounted catch. Among the most prominent is ...


Misspecification Of The Random Effect Structure: Implications For The Linear Mixed Model, Brandon LeBeau 2018 University of Iowa

Misspecification Of The Random Effect Structure: Implications For The Linear Mixed Model, Brandon Lebeau

Department of Psychological and Quantitative Foundations Publications

The linear mixed model is a commonly used model for longitudinal or nested data due to its ability to account for the dependency of nested data. Researchers typically rely on the random effects to adequately account for the dependency due to correlated data, however serial correlation can also be used. If the random effect structure is misspecified (perhaps due to convergence problems), can the addition of serial correlation overcome this misspecification and allow for unbiased estimation and accurate inferences? This study explored this question with a simulation. Simulation results show that the fixed effects are unbiased, however inflation of the ...


The Influence Of Parental Control And Parent-Child Relational Qualities On Adolescent Internet Addiction: A 3-Year Longitudinal Study In Hong Kong, Daniel T. L. Shek, Xiaoqin Zhu, Cecilia M. S. Ma 2018 University of Kentucky

The Influence Of Parental Control And Parent-Child Relational Qualities On Adolescent Internet Addiction: A 3-Year Longitudinal Study In Hong Kong, Daniel T. L. Shek, Xiaoqin Zhu, Cecilia M. S. Ma

Pediatrics Faculty Publications

This study investigated how parental behavioral control, parental psychological control, and parent-child relational qualities predicted the initial level and rate of change in adolescent internet addiction (IA) across the junior high school years. The study also investigated the concurrent and longitudinal effects of different parenting factors on adolescent IA. Starting from the 2009/2010 academic year, 3,328 Grade 7 students (Mage = 12.59 ± 0.74 years) from 28 randomly selected secondary schools in Hong Kong responded on a yearly basis to a questionnaire measuring multiple constructs including socio-demographic characteristics, perceived parenting characteristics, and IA. Individual growth curve (IGC ...


Longitudinal Tracking Of Physiological State With Electromyographic Signals., Robert Warren Stallard 2018 University of Louisville

Longitudinal Tracking Of Physiological State With Electromyographic Signals., Robert Warren Stallard

Electronic Theses and Dissertations

Electrophysiological measurements have been used in recent history to classify instantaneous physiological configurations, e.g., hand gestures. This work investigates the feasibility of working with changes in physiological configurations over time (i.e., longitudinally) using a variety of algorithms from the machine learning domain. We demonstrate a high degree of classification accuracy for a binary classification problem derived from electromyography measurements before and after a 35-day bedrest. The problem difficulty is increased with a more dynamic experiment testing for changes in astronaut sensorimotor performance by taking electromyography and force plate measurements before, during, and after a jump from a small ...


Self-Reported Risk And Delinquent Behavior And Problem Behavioral Intention In Hong Kong Adolescents: The Role Of Moral Competence And Spirituality, Daniel T. L. Shek, Xiaoqin Zhu 2018 University of Kentucky

Self-Reported Risk And Delinquent Behavior And Problem Behavioral Intention In Hong Kong Adolescents: The Role Of Moral Competence And Spirituality, Daniel T. L. Shek, Xiaoqin Zhu

Pediatrics Faculty Publications

Based on the six-wave data collected from Grade 7 to Grade 12 students (N = 3,328 at Wave 1), this pioneer study examined the development of problem behaviors (risk and delinquent behavior and problem behavioral intention) and the predictors (moral competence and spirituality) among adolescents in Hong Kong. Individual growth curve models revealed that while risk and delinquent behavior accelerated and then slowed down in the high school years, adolescent problem behavioral intention slightly accelerated over time. After controlling the background socio-demographic factors, moral competence and spirituality were negatively associated with risk and delinquent behavior as well as problem behavioral ...


An Investigation Of The Effects Of Taking Remedial Math In College On Degree Attainment And College Gpa Using Multiple Imputation And Propensity Score Matching, Meghan A. Clovis 2018 Florida International University

An Investigation Of The Effects Of Taking Remedial Math In College On Degree Attainment And College Gpa Using Multiple Imputation And Propensity Score Matching, Meghan A. Clovis

FIU Electronic Theses and Dissertations

Enrollment in degree-granting postsecondary institutions in the U.S. is increasing, as are the numbers of students entering academically underprepared. Students in remedial mathematics represent the largest percentage of total enrollment in remedial courses, and national statistics indicate that less than half of these students pass all of the remedial math courses in which they enroll. In response to the low pass rates, numerous studies have been conducted into the use of alternative modes of instruction to increase passing rates. Despite myriad studies into course redesign, passing rates have seen no large-scale improvement. Lacking is a thorough investigation into preexisting ...


Negative Year In School Effect: Extending Scope And Strengthening Causal Claims [Accepted Manuscript], Philip D. Parker, Herbert W. Marsh, Felix Thoemmes, Nicholas Biddle 2018 Australian Catholic University

Negative Year In School Effect: Extending Scope And Strengthening Causal Claims [Accepted Manuscript], Philip D. Parker, Herbert W. Marsh, Felix Thoemmes, Nicholas Biddle

Faculty of Health Sciences Publications

The Negative Year in School Effect (NYiSE) claims that grade-relative-to-age influences academic self-concept. Being young for your grade is associated with lower self-concept, whereas being old for your grade is associated with higher self-concept. We extend this research in several ways. First, we aim to improve causal claims for the NYiSE by utilizing birth month as an instrumental variable. Using the Longitudinal Study of Australian Youth we find that the NYiSE is negative under instrumental variable regression. Given that NYiSE has focused on math self-concept we show that the effect extends to other measures of math, general academic, and English ...


Building A Better Risk Prevention Model, Steven Hornyak 2018 Houston County Schools

Building A Better Risk Prevention Model, Steven Hornyak

National Youth-At-Risk Conference Savannah

This presentation chronicles the work of Houston County Schools in developing a risk prevention model built on more than ten years of longitudinal student data. In its second year of implementation, Houston At-Risk Profiles (HARP), has proven effective in identifying those students most in need of support and linking them to interventions and supports that lead to improved outcomes and significantly reduces the risk of failure.


Modelling The Common Risk Among Equities Using A New Time Series Model, Jingjia Chu 2018 The University of Western Ontario

Modelling The Common Risk Among Equities Using A New Time Series Model, Jingjia Chu

Electronic Thesis and Dissertation Repository

A new additive structure of multivariate GARCH model is proposed where the dynamic changes of the conditional correlation between the stocks are aggregated by the common risk term. The observable sequence is divided into two parts, a common risk term and an individual risk term, both following a GARCH type structure. The conditional volatility of each stock will be the sum of these two conditional variance terms. All the conditional volatility of the stock can shoot up together because a sudden peak of the common volatility is a sign of the system shock.

We provide sufficient conditions for strict stationarity ...


Improved Methods And Selecting Classification Types For Time-Dependent Covariates In The Marginal Analysis Of Longitudinal Data, I-Chen Chen 2018 University of Kentucky

Improved Methods And Selecting Classification Types For Time-Dependent Covariates In The Marginal Analysis Of Longitudinal Data, I-Chen Chen

Theses and Dissertations--Epidemiology and Biostatistics

Generalized estimating equations (GEE) are popularly utilized for the marginal analysis of longitudinal data. In order to obtain consistent regression parameter estimates, these estimating equations must be unbiased. However, when certain types of time-dependent covariates are presented, these equations can be biased unless an independence working correlation structure is employed. Moreover, in this case regression parameter estimation can be very inefficient because not all valid moment conditions are incorporated within the corresponding estimating equations. Therefore, approaches using the generalized method of moments or quadratic inference functions have been proposed for utilizing all valid moment conditions. However, we have found that ...


Improved Standard Error Estimation For Maintaining The Validities Of Inference In Small-Sample Cluster Randomized Trials And Longitudinal Studies, Whitney Ford Tanner 2018 University of Kentucky

Improved Standard Error Estimation For Maintaining The Validities Of Inference In Small-Sample Cluster Randomized Trials And Longitudinal Studies, Whitney Ford Tanner

Theses and Dissertations--Epidemiology and Biostatistics

Data arising from Cluster Randomized Trials (CRTs) and longitudinal studies are correlated and generalized estimating equations (GEE) are a popular analysis method for correlated data. Previous research has shown that analyses using GEE could result in liberal inference due to the use of the empirical sandwich covariance matrix estimator, which can yield negatively biased standard error estimates when the number of clusters or subjects is not large. Many techniques have been presented to correct this negative bias; However, use of these corrections can still result in biased standard error estimates and thus test sizes that are not consistently at their ...


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