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1048 full-text articles. Page 1 of 27.

Strategies To Stabilize Locally Grown Produce For Year-Round Sales: A Feasibility Study, Sam Beattie, Lester Wilson, Aubrey Mendonca, Stéphanie Jung 2017 Iowa State University

Strategies To Stabilize Locally Grown Produce For Year-Round Sales: A Feasibility Study, Sam Beattie, Lester Wilson, Aubrey Mendonca, Stéphanie Jung

Stéphanie Jung

Local markets are dependent on fresh-grown products that are available only on a seasonal basis. This project looked at possible ways to preserve fruits and vegetables for profitable sales in the offseason.


Gelatinization Properties Of Starches From Three Successive Generations Of Six Exotic Corn Lines Grown In Two Locations, Y. Ji, L. M. Pollak, S. Duvick, K. Seetharaman, Philip Dixon, Pamela J. White 2017 Iowa State University

Gelatinization Properties Of Starches From Three Successive Generations Of Six Exotic Corn Lines Grown In Two Locations, Y. Ji, L. M. Pollak, S. Duvick, K. Seetharaman, Philip Dixon, Pamela J. White

Philip Dixon

The objectives of this research were to evaluate the intra- and interpopulation variability in gelatinization properties of starches from exotic corn lines and their derivatives when grown 1) during two successive years in the same location; and 2) in both temperate and tropical environments. Six novel exotic corn lines (two 100% exotic and four 25% exotic derived from a breeding cross developed by crossing an exotic hybrid with Corn Belt lines) were selected for this research because their starches have significantly different (and potentially useful) thermal properties from those found in starch from normal Corn Belt corn. The Sn (n ...


The University Of Iowa Biomass Energy Sustainability Index: A Decision-Making Tool For The University Of Iowa Biomass Partnership Project, Liz Christiansen, Ingrid Gronstal Anderson, Ferman Milster, Sara Maples, Aaron Strong, Adam Ward, Eric Tate, Tyler Priest, Emily A. Heaton, Lisa A. Schulte Moore, Richard B. Hall, John Tyndall, Maeraj Hafiz Sheikh, Daryl Smith 2017 University of Iowa

The University Of Iowa Biomass Energy Sustainability Index: A Decision-Making Tool For The University Of Iowa Biomass Partnership Project, Liz Christiansen, Ingrid Gronstal Anderson, Ferman Milster, Sara Maples, Aaron Strong, Adam Ward, Eric Tate, Tyler Priest, Emily A. Heaton, Lisa A. Schulte Moore, Richard B. Hall, John Tyndall, Maeraj Hafiz Sheikh, Daryl Smith

Lisa A. Schulte Moore

Work continued on a plan to increase the renewable, sustainable fuel sources available to power operations at the University of Iowa in Iowa City. A team of researchers from multiple institutions collaborated to create a tool that would allow the UI to evaluate its alternative energy options more effectively.


Mechanistic Mathematical Models: An Underused Platform For Hpv Research, Marc Ryser, Patti Gravitt, Evan R. Myers 2017 George Washington University

Mechanistic Mathematical Models: An Underused Platform For Hpv Research, Marc Ryser, Patti Gravitt, Evan R. Myers

Global Health Faculty Publications

Health economic modeling has become an invaluable methodology for the design and evaluation of clinical and public health interventions against the human papillomavirus (HPV) and associated diseases. At the same time, relatively little attention has been paid to a different yet complementary class of models, namely that of mechanistic mathematical models. The primary focus of mechanistic mathematical models is to better understand the intricate biologic mechanisms and dynamics of disease. Inspired by a long and successful history of mechanistic modeling in other biomedical fields, we highlight several areas of HPV research where mechanistic models have the potential to advance the ...


Firing Rate Heterogeneity And Consequences For Coding In Feedforward Circuits, Cheng Ly, Gary Marsat 2017 Virginia Commonwealth University

Firing Rate Heterogeneity And Consequences For Coding In Feedforward Circuits, Cheng Ly, Gary Marsat

Biology and Medicine Through Mathematics Conference

No abstract provided.


Methods For Parameter Estimation Of A Stochastic Seir Model, Kaitlyn Martinez 2017 Colorado School of Mines

Methods For Parameter Estimation Of A Stochastic Seir Model, Kaitlyn Martinez

Biology and Medicine Through Mathematics Conference

No abstract provided.


Shape Features Underlying The Perception Of Liquids, Jan Jaap R. van Assen, Pascal Barla, Roland W. Fleming 2017 Department of Psychology, Justus-Liebig-University Giessen

Shape Features Underlying The Perception Of Liquids, Jan Jaap R. Van Assen, Pascal Barla, Roland W. Fleming

MODVIS Workshop

No abstract provided.


Mortgage Transition Model Based On Loanperformance Data, Shuyao Yang 2017 Washington University in St. Louis

Mortgage Transition Model Based On Loanperformance Data, Shuyao Yang

Arts & Sciences Electronic Theses and Dissertations

The unexpected increase in loan default on the mortgage market is widely considered to be one of the main cause behind the economic crisis. To provide some insight on loan delinquency and default, I analyze the mortgage performance data from Fannie Mae website and investigate how economic factors and individual loan and borrower information affect the events of default and prepaid. Various delinquency status including default and prepaid are treated as discrete states of a Markov chain. One-step transition probabilities are estimated via multinomial logistic models. We find that in general current loan-to-value ratio, credit score, unemployment rate, and interest ...


Gilmore Girls And Instagram: A Statistical Look At The Popularity Of The Television Show Through The Lens Of An Instagram Page, Brittany Simmons 2017 Chapman University

Gilmore Girls And Instagram: A Statistical Look At The Popularity Of The Television Show Through The Lens Of An Instagram Page, Brittany Simmons

Student Research Day Abstracts and Posters

After going on the Warner Brothers Tour in December of 2015, I created a Gilmore Girls Instagram account. This account, which started off as a way for me to create edits of the show and post my photos from the tour turned into something bigger than I ever could have imagined. In just over a year I have over 55,000 followers. I post content including revival news, merchandise, and edits of the show that have been featured in Entertainment Weekly, Bustle, E! News, People Magazine, Yahoo News, & GilmoreNews.

I created a dataset of qualitative and quantitative outcomes from my ...


Comparision Of Survival Curves Between Cox Proportional Hazards, Random Forests, And Conditional Inference Forests In Survival Analysis, Brandon Weathers, Richard Cutler Dr. 2017 Utah State University

Comparision Of Survival Curves Between Cox Proportional Hazards, Random Forests, And Conditional Inference Forests In Survival Analysis, Brandon Weathers, Richard Cutler Dr.

All Graduate Plan B and other Reports

Survival analysis methods are a mainstay of the biomedical fields but are finding increasing use in other disciplines including finance and engineering. A widely used tool in survival analysis is the Cox proportional hazards regression model. For this model, all the predicted survivor curves have the same basic shape, which may not be a good approximation to reality. In contrast the Random Survival Forests does not make the proportional hazards assumption and has the flexibility to model survivor curves that are of quite different shapes for different groups of subjects. We applied both techniques to a number of publicly available ...


A Comparison Of Statistical Methods Relating Pairwise Distance To A Binary Subject-Level Covariate, Rachael Stone 2017 Utah State University

A Comparison Of Statistical Methods Relating Pairwise Distance To A Binary Subject-Level Covariate, Rachael Stone

All Graduate Plan B and other Reports

A community ecologist provided a motivating data set involving a certain animal species with two behavior groups, along with a pairwise genetic distance matrix among individuals. Many community ecologists have analyzed similar data sets with a method known as the Hopkins method, testing for an association between the subject-level covariate (behavior group) and the pairwise distance. This community ecologist wanted to know if they used the Hopkins method, would their results be meaningful? Their question inspired this thesis work, where a different data set was used for confidentiality reasons. Multiple methods (Hopkins method, ADONIS, ANOSIM, and Distance Regression) were used ...


Washington State Public Teachers' Ambient Positional Instability From A Statistical Approach Of Retrospective Study & Prospective Study, Bowen Cai, Robert Boruch 2017 University of Pennsylvania

Washington State Public Teachers' Ambient Positional Instability From A Statistical Approach Of Retrospective Study & Prospective Study, Bowen Cai, Robert Boruch

GSE Publications

The purpose of this research is to study the movements of teachers’ churn rate in the state of Washington over the past 14 years. The research of teachers’ churn rate is an integrative study, with retrospective part and prospective part. Retrospective study includes the analysis of descriptive statistics (level I), statistical inference (level II) and causal inference (level III) (Berk, R.A. (2016) Statistical Learning from a Regression Perspective. Philadelphia, PA: Springer). Prospective study is mainly about forecasting and statistical inference that generated from the predictions. In this research, we are using longitudinal data analysis. The good point of longitudinal ...


Performance Of Imputation Algorithms On Artificially Produced Missing At Random Data, Tobias O. Oketch 2017 East Tennessee State University

Performance Of Imputation Algorithms On Artificially Produced Missing At Random Data, Tobias O. Oketch

Electronic Theses and Dissertations

Missing data is one of the challenges we are facing today in modeling valid statistical models. It reduces the representativeness of the data samples. Hence, population estimates, and model parameters estimated from such data are likely to be biased.

However, the missing data problem is an area under study, and alternative better statistical procedures have been presented to mitigate its shortcomings. In this paper, we review causes of missing data, and various methods of handling missing data. Our main focus is evaluating various multiple imputation (MI) methods from the multiple imputation of chained equation (MICE) package in the statistical software ...


Modelling Cash Crop Growth In Tn, Spencer Weston 2017 University of Tennessee

Modelling Cash Crop Growth In Tn, Spencer Weston

University of Tennessee Honors Thesis Projects

No abstract provided.


A Bayesian Variable Selection Method With Applications To Spatial Data, Xiahan Tang 2017 University of Arkansas, Fayetteville

A Bayesian Variable Selection Method With Applications To Spatial Data, Xiahan Tang

Theses and Dissertations

This thesis first describes the general idea behind Bayes Inference, various sampling methods based on Bayes theorem and many examples. Then a Bayes approach to model selection, called Stochastic Search Variable Selection (SSVS) is discussed. It was originally proposed by George and McCulloch (1993). In a normal regression model where the number of covariates is large, only a small subset tend to be significant most of the times. This Bayes procedure specifies a mixture prior for each of the unknown regression coefficient, the mixture prior was originally proposed by Geweke (1996). This mixture prior will be updated as data becomes ...


On Post-Selection Confidence Intervals In Linear Regression, Xinwei Zhang 2017 Washington University in St. Louis

On Post-Selection Confidence Intervals In Linear Regression, Xinwei Zhang

Arts & Sciences Electronic Theses and Dissertations

The general goal of this thesis is to investigate and examine some issues about post-selection inference which arises from the setting where statistical inference is carried out after a datadriven model selection step. In this setting, the classical inference theory which requires a fixed priori model becomes invalid since the selected model is a result of random event. Hence, a common practice in applied research which ignores the model selection and builds up confidence interval will result in misleading or even false conclusion. In this thesis, specifically, we first discusses some examples to show how the classical inference theory loses ...


Statistical Analysis Of Markovian Queueing Models Of Limit Order Books, Yiyao Luo 2017 Washington University in St. Louis

Statistical Analysis Of Markovian Queueing Models Of Limit Order Books, Yiyao Luo

Arts & Sciences Electronic Theses and Dissertations

The objective of this thesis is to investigate the suitability of some Markovian queueing models in being able to effectively describe the dynamical properties of a limit order book more specifically. We review and compare the assumptions proposed by Huang et al.[Quantitative Finance,12,547-557(2012)] and Cont et al.[SIAM Journal for Financial Mathematics,4,1- 25(2013)], and estimate the intensity parameters in both ways, based on real data of a stock on the Nasdaq Stock Market. Trough comparing by cumulative distribution functions of first-passage time to state 0, we will hsow that the estimators of Cont ...


Linear Regression, Model Averaging, And Bayesian Techniques For Predicting Chemical Activities From Structure, Jarad B. Niemi, Gerald J. Niemi 2017 Iowa State University

Linear Regression, Model Averaging, And Bayesian Techniques For Predicting Chemical Activities From Structure, Jarad B. Niemi, Gerald J. Niemi

Jarad Niemi

A primary goal of quantitative structure-activity relationships (QSARs) and quantitative structure-property relationships (QSPRs) is to predict chemical activities from chemical structure. Chemical structure can be quantified in many ways resulting in hundreds, if not thousands, of measurements for every chemical. Chemical activities measures how the chemical interacts with other chemicals, e.g. toxicity, biodegradability, boiling point, and vapor pressure. Typically there are more chemical structure measurements than chemicals being measured, the so-called large-p, small-n problem. Here we review some of the statistical procedures that have been commonly used to explore these problems in the past and provide several examples of ...


Implementing Propensity Score Matching With Network Data: The Effect Of Gatt On Bilateral Trade, Luca De Benedictis, Bruno Arpino, Alessandra Mattei 2017 Universitat Pompeu Fabra

Implementing Propensity Score Matching With Network Data: The Effect Of Gatt On Bilateral Trade, Luca De Benedictis, Bruno Arpino, Alessandra Mattei

Luca De Benedictis

Motivated by the evaluation of the causal effect of the General Agreement on Tariffs and Trade on bilateral international trade flows, we investigate the role of network structure in propensity score matching under the assumption of strong ignorability. We study the sensitivity of causal inference with respect to the presence of characteristics of the network in the set of confounders conditional on which strong ignorability is assumed to hold. We find that estimates of the average causal effect are highly sensitive to the presence of node-level network statistics in the set of confounders. Therefore, we argue that estimates may suffer ...


Statistically Analyzing Assembly Line Processing Times Through Incorporation Of Product Variation, Kyle Rehr, Matthew Farr 2017 Murray State University

Statistically Analyzing Assembly Line Processing Times Through Incorporation Of Product Variation, Kyle Rehr, Matthew Farr

Scholars Week

Timing methods and performance metrics are important in the heavily industrialized world we live in. Industrial plants use metrics to measure quality of production, help make decisions, and drive the strategy of the organization. However, there are many factors to be considered when measuring performance based on a metric; of which we will be analyzing the importance of product variation. We will be analyzing assembly line timings, whilst controlling for product variance, to show the importance differences between products makes in one’s ability to predict performance. In addition, we will be analyzing the current “statistical” methods used by an ...


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