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Monopoly, Regulation, And Innovation, Matt Bogard 2010 Western Kentucky University

Monopoly, Regulation, And Innovation, Matt Bogard

Economics Faculty Publications

Recently the Justice department has started investigations into alleged anti-trust violations by Monsanto. This has helped fuel a lot of already hyped discontent with one of the world’s leaders in innovative solutions for sustainable agriculture. This article discusses how the regulatory environment could possibly have contributed to more concentration and power in the biotech industry. Increasing regulation would likely have the opposite effect of creating a level playing field in the agriculture industry. From AgWeb, March 27,2010 http://www.agweb.com/blog/Economic_Sense_190/Monopoly_Regulation__and_Innovation_10771/


A Re-Defined And Generalized Percent-Overlap-Of-Activation Measure For Studies Of Fmri Reproducibility And Its Use In Identifying Outlier Activation Maps, Ranjan Maitra 2010 Iowa State University

A Re-Defined And Generalized Percent-Overlap-Of-Activation Measure For Studies Of Fmri Reproducibility And Its Use In Identifying Outlier Activation Maps, Ranjan Maitra

Statistics Publications

Functional Magnetic Resonance Imaging (fMRI) is a popular noninvasive modality to investigate activation in the human brain. The end result of most fMRI experiments is an activation map corresponding to the given paradigm. These maps can vary greatly from one study to the next, so quantifying the reliability of identified activation over several fMRI studies is important. The percent overlap of activation (Rombouts et al., 1998 and Machielsen et al., 2000) is a global reliability measure between activation maps drawn from any two fMRI studies. A slightly modified but more intuitive measure is provided by the Jaccard (1901) coefficient of ...


Synthetic Magnetic Resonance Imaging Revisited, Ranjan Maitra, John J. Riddles 2010 Iowa State University

Synthetic Magnetic Resonance Imaging Revisited, Ranjan Maitra, John J. Riddles

Statistics Publications

Synthetic magnetic resonance (MR) imaging is an approach suggested in the literature to predict MR images at different design parameter settings from at least three observed MR scans. However, performance is poor when no regularization is used in the estimation and otherwise computationally impractical to implement for three-dimensional imaging methods. We propose a method which accounts for spatial context in MR images by the imposition of a Gaussian Markov Random Field (MRF) structure on a transformation of the spin-lattice relaxation time, the spin-spin relaxation time and the proton density at each voxel. The MRF structure is specified through a Matrix ...


Statistical Power Analysis Using Sas And R, Peter Osmena 2010 California Polytechnic State University, San Luis Obispo

Statistical Power Analysis Using Sas And R, Peter Osmena

Statistics

Statistical power is something that has to be considered when designing an experiment. The power is used to determine the usefulness of the test. In this paper the concept of power and what it is will be discussed. A general ANOVA test and a Chi Squared test will be discussed in greater depth. Computers make these power calculations relatively easy to compute, considering they are used right. SAS and R both have the capabilities to make these calculations for a different variety of tests. Calculating power for a general ANOVA test and a Chi Squared test using these programs are ...


Parallel Evolution Of Character Displacement Driven By Competitive Selection In Terrestrial Salamanders, Dean C. Adams 2010 Iowa State University

Parallel Evolution Of Character Displacement Driven By Competitive Selection In Terrestrial Salamanders, Dean C. Adams

Ecology, Evolution and Organismal Biology Publications

Parallel evolution can occur when common environmental factors exert similar selective forces on morphological variation in populations in different geographic localities. Competition can also generate morphological shifts, and if competing species co-occur in multiple geographic regions, then repeated instances of competitively-driven morphological divergence (character displacement) can occur. Despite the importance of character displacement for inferring the role of selection in morphological evolution however, replicated instances of sympatric morphological divergence are understudied. I tested the hypothesis that interspecific competition generated patterns of parallel morphological divergence in multiple geographic locations where two competing salamander species, Plethodon jordani and P. teyahalee, come into ...


Software Internationalization: A Framework Validated Against Industry Requirements For Computer Science And Software Engineering Programs, John Huân Vũ 2010 California Polytechnic State University, San Luis Obispo

Software Internationalization: A Framework Validated Against Industry Requirements For Computer Science And Software Engineering Programs, John Huân Vũ

Master's Theses

View John Huân Vũ's thesis presentation at http://youtu.be/y3bzNmkTr-c.

In 2001, the ACM and IEEE Computing Curriculum stated that it was necessary to address "the need to develop implementation models that are international in scope and could be practiced in universities around the world." With increasing connectivity through the internet, the move towards a global economy and growing use of technology places software internationalization as a more important concern for developers. However, there has been a "clear shortage in terms of numbers of trained persons applying for entry-level positions" in this area. Eric Brechner, Director of Microsoft ...


Functional Generalized Linear Models With Images As Predictors, Philip T. Reiss, R. Todd Ogden 2010 New York University

Functional Generalized Linear Models With Images As Predictors, Philip T. Reiss, R. Todd Ogden

Philip T. Reiss

Functional principal component regression (FPCR) is a promising new method for regressing scalar outcomes on functional predictors. In this paper we present a theoretical justification for the use of principal components in functional regression. FPCR is then extended in two directions: from linear to the generalized linear modeling, and from univariate signal predictors to high-resolution image predictors. We show how to implement the method efficiently by adapting generalized additive model technology to the functional regression context. A technique is proposed for estimating simultaneous confidence bands for the coefficient function; in the neuroimaging setting, this yields a novel means to identify ...


Patent Examination Policy And The Social Costs Of Examiner Allowance And Rejection Errors, Ron D. Katznelson 2010 Bi-Level Technologies

Patent Examination Policy And The Social Costs Of Examiner Allowance And Rejection Errors, Ron D. Katznelson

Ron D. Katznelson

No abstract provided.


Empirical Probability Distribution Of Journal Impact Factor And Over-The-Samples Stability In Its Estimated Parameters, Sudhanshu K. Mishra 2010 North-Eastern Hill University, Shillong (India)

Empirical Probability Distribution Of Journal Impact Factor And Over-The-Samples Stability In Its Estimated Parameters, Sudhanshu K. Mishra

Sudhanshu K Mishra

The data on JIFs provided by Thomson Scientific can only be considered as a sample since they do not cover the entire universe of those documents that cite an intellectual output (paper, article, etc) or are cited by others. Then, questions arise if the empirical distribution (best fit to the JIF data for any particular year) really represents the true or universal distribution, are its estimated parameters stable over the samples and do they have some scientific interpretation? It may be noted that if the estimated parameters do not exhibit stability over the samples (while the sample size is large ...


Estimating The Proportion Of Equivalently Expressed Genes In Microarray Data Based On Transformed Test Statistics, SHUO JIAO, Shunpu Zhang 2010 Fred Hutchinson Cancer Research Center

Estimating The Proportion Of Equivalently Expressed Genes In Microarray Data Based On Transformed Test Statistics, Shuo Jiao, Shunpu Zhang

Shuo Jiao

In microarray data analysis, false discovery rate (FDR) is now widely accepted as the control criterion to account for multiple hypothesis testing. The proportion of equivalently expressed genes (π0) is a key component to be estimated in the estimation of FDR. Some commonly used π0 estimators (BUM, SPLOSH, QVALUE, and LBE ) are all based on p-values, and they are essentially upper bounds of π0. The simulations we carried out show that these four methods significantly overestimate the true π0 when differentially expressed genes and equivalently expressed genes are not well separated. To solve this problem, we first introduce a novel ...


Targeting The Optimal Design In Randomized Clinical Trials With Binary Outcomes And No Covariate, Antoine Chambaz, Mark J. van der Laan 2010 Laboratoire MAP5, Université Paris Descartes and CNRS

Targeting The Optimal Design In Randomized Clinical Trials With Binary Outcomes And No Covariate, Antoine Chambaz, Mark J. Van Der Laan

U.C. Berkeley Division of Biostatistics Working Paper Series

This article is devoted to the asymptotic study of adaptive group sequential designs in the case of randomized clinical trials with binary treatment, binary outcome and no covariate. By adaptive design, we mean in this setting a clinical trial design that allows the investigator to dynamically modify its course through data-driven adjustment of the randomization probability based on data accrued so far, without negatively impacting on the statistical integrity of the trial. By adaptive group sequential design, we refer to the fact that group sequential testing methods can be equally well applied on top of adaptive designs. Prior to collection ...


Targeted Maximum Likelihood Based Causal Inference, Mark J. van der Laan 2010 University of California - Berkeley

Targeted Maximum Likelihood Based Causal Inference, Mark J. Van Der Laan

U.C. Berkeley Division of Biostatistics Working Paper Series

Given causal graph assumptions, intervention-specific counterfactual distributions of the data can be defined by the so called G-computation formula, which is obtained by carrying out these interventions on the likelihood of the data factorized according to the causal graph. The obtained G-computation formula represents the counterfactual distribution the data would have had if this intervention would have been enforced on the system generating the data. A causal effect of interest can now be defined as some difference between these counterfactual distributions indexed by different interventions. For example, the interventions can represent static treatment regimens or individualized treatment rules that assign ...


Comparative Efficacy Versus Effectiveness Of Initial Antiretroviral Therapy In Clinical Trials Versus Routine Care, Justin S. Routman, James H. Willig, Andrew O. Westfall, Sarah R. Abroms, Mohit Varshney, Sunil Adusumilli, Jeroan J. Allison, Karen G. Savage, Michael S. Saag, Michael J. Mugavero 2010 University of Alabama at Birmingham

Comparative Efficacy Versus Effectiveness Of Initial Antiretroviral Therapy In Clinical Trials Versus Routine Care, Justin S. Routman, James H. Willig, Andrew O. Westfall, Sarah R. Abroms, Mohit Varshney, Sunil Adusumilli, Jeroan J. Allison, Karen G. Savage, Michael S. Saag, Michael J. Mugavero

Population and Quantitative Health Sciences Publications

BACKGROUND: The applicability of clinical trial findings (efficacy) to the routine care setting (effectiveness) may be limited because of study eligibility criteria and volunteer bias. Although well-chronicled in many conditions, the efficacy versus effectiveness of antiretroviral therapy (ART) remains understudied.

METHODS: A retrospective study of the University of Alabama at Birmingham 1917 Clinic Cohort evaluated ART-naive patients who started ART from 1 January 2000 through 31 December 2006. Patients received ART through clinical trials or routine care. Multivariable logistic and linear regression models were fit to evaluate factors associated with virological failure (virological failure was defined as a viral load ...


A Note On Empirical Sample Distribution Of Journal Impact Factors In Major Discipline Groups, Sudhanshu K. Mishra 2010 North-Eastern Hill University, Shillong (India)

A Note On Empirical Sample Distribution Of Journal Impact Factors In Major Discipline Groups, Sudhanshu K. Mishra

Sudhanshu K Mishra

What type of statistical distribution do the Journal Impact Factors follow? In the past, researchers have hypothesized various types of statistical distributions underlying the generation mechanism of journal impact factors. These are: lognormal, normal, approximately normal, Weibull, negative exponential, combination of exponentials, Poisson, Generalized inverse Gaussian-Poisson, negative binomial, generalized Waring, gamma, etc. It is pertinent to note that the major characteristics of JIF data lay in the asymmetry and non-mesokurticity. The present study, frequently encounters Burr-XII, inverse Burr-III (Dagum), Johnson SU, and a few other distributions closely related to Burr distributions to best fit the JIF data in subject groups ...


Bio-Creep In Non-Inferiority Clinical Trials, Siobhan P. Everson-Stewart, Scott S. Emerson 2010 University of Washington - Seattle Campus

Bio-Creep In Non-Inferiority Clinical Trials, Siobhan P. Everson-Stewart, Scott S. Emerson

UW Biostatistics Working Paper Series

After a non-inferiority clinical trial, a new therapy may be accepted as effective, even if its treatment effect is slightly smaller than the current standard. It is therefore possible that, after a series of trials where the new therapy is slightly worse than the preceding drugs, an ineffective or harmful therapy might be incorrectly declared efficacious; this is known as “bio-creep.” Several factors may influence the rate at which bio-creep occurs, including the distribution of the effects of the new agents being tested and how that changes over time, the choice of active comparator, the method used to model the ...


Estimates Of Information Growth In Longitudinal Clinical Trials, Abigail Shoben, Kyle Rudser, Scott S. Emerson 2010 University of Washington

Estimates Of Information Growth In Longitudinal Clinical Trials, Abigail Shoben, Kyle Rudser, Scott S. Emerson

UW Biostatistics Working Paper Series

In group sequential clinical trials, it is necessary to estimate the amount of information present at interim analysis times relative to the amount of information that would be present at the final analysis. If only one measurement is made per individual, this is often the ratio of sample sizes available at the interim and final analyses. However, as discussed by Wu and Lan (1992), when the statistic of interest is a change over time, as with longitudinal data, such an approach overstates the information. In this paper, we discuss other problems that can result in overestimating the information, such as ...


Effects Of Socioeconomic Status On Brain Development, And How Cognitive Neuroscience May Contribute To Levelling The Playing Field, Rajeev Raizada, Mark M. Kishiyama 2010 Dartmouth College

Effects Of Socioeconomic Status On Brain Development, And How Cognitive Neuroscience May Contribute To Levelling The Playing Field, Rajeev Raizada, Mark M. Kishiyama

Open Dartmouth: Published works by Dartmouth faculty

The study of socioeconomic status (SES) and the brain finds itself in a circumstance unusual for Cognitive Neuroscience: large numbers of questions with both practical and scientific importance exist, but they are currently under-researched and ripe for investigation. This review aims to highlight these questions, to outline their potential significance, and to suggest routes by which they might be approached. Although remarkably few neural studies have been carried out so far, there exists a large literature of previous behavioural work. This behavioural research provides an invaluable guide for future neuroimaging work, but also poses an important challenge for it: how ...


Research Poster: Hydrological Impacts Of Climate Change On Colorado Basin, Peng Jiang, Zhongbo Yu 2010 University of Nevada, Las Vegas

Research Poster: Hydrological Impacts Of Climate Change On Colorado Basin, Peng Jiang, Zhongbo Yu

2010 Annual Nevada NSF EPSCoR Climate Change Conference

Research poster


Research Poster: Climate Prediction Downscaling Of Temperature And Precipitation In The Great Basin Region, Ramesh Vellore, Benjamin J. Hatchett, Darko Koracin 2010 Desert Research Institute

Research Poster: Climate Prediction Downscaling Of Temperature And Precipitation In The Great Basin Region, Ramesh Vellore, Benjamin J. Hatchett, Darko Koracin

2010 Annual Nevada NSF EPSCoR Climate Change Conference

Research poster


Research Poster: An Overview Of Progress In Nsf Epscor Project Entitled, “Reducing Cloud Uncertainties In Climate Models”, Subhashree Mishra, David L. Mitchell, W. Patrick Arnott 2010 Desert Research Institute & University of Nevada, Reno

Research Poster: An Overview Of Progress In Nsf Epscor Project Entitled, “Reducing Cloud Uncertainties In Climate Models”, Subhashree Mishra, David L. Mitchell, W. Patrick Arnott

2010 Annual Nevada NSF EPSCoR Climate Change Conference

Research poster


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