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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 ...


Session D-1: Lies, Damn Lies, And Statistics, Peter Dong, Joseph Traina 2017 Illinois Mathematics and Science Academy

Session D-1: Lies, Damn Lies, And Statistics, Peter Dong, Joseph Traina

Professional Learning Day

The crucial and sometimes difficult areas of data analysis and statistics can be made clearer by looking at examples of how they can be done badly - examples which, unfortunately, are easy to find. We share our experience teaching a short course which examines disingenuous graphs, biased surveys, deliberately misworded statements, and other methods of misrepresenting data. The negative examples provide an opportunity to discuss how statistics should properly be done, and explain what can happen when statistics are used incorrectly. We include a discussion of the failure of polls to predict the outcome of the presidential election.


Evaluation Of Progress Towards The Unaids 90-90-90 Hiv Care Cascade: A Description Of Statistical Methods Used In An Interim Analysis Of The Intervention Communities In The Search Study, Laura Balzer, Joshua Schwab, Mark J. van der Laan, Maya L. Petersen 2017 Department of Biostatistics, Harvard T.H. Chan School of Public Heath

Evaluation Of Progress Towards The Unaids 90-90-90 Hiv Care Cascade: A Description Of Statistical Methods Used In An Interim Analysis Of The Intervention Communities In The Search Study, Laura Balzer, Joshua Schwab, Mark J. Van Der Laan, Maya L. Petersen

U.C. Berkeley Division of Biostatistics Working Paper Series

WHO guidelines call for universal antiretroviral treatment, and UNAIDS has set a global target to virally suppress most HIV-positive individuals. Accurate estimates of population-level coverage at each step of the HIV care cascade (testing, treatment, and viral suppression) are needed to assess the effectiveness of "test and treat" strategies implemented to achieve this goal. The data available to inform such estimates, however, are susceptible to informative missingness: the number of HIV-positive individuals in a population is unknown; individuals tested for HIV may not be representative of those whom a testing intervention fails to reach, and HIV-positive individuals with a viral ...


Adaptive Non-Inferiority Margins Under Observable Non-Constancy, Brett S. Hanscom, Deborah J. Donnell, Brian D. Williamson, Jim Hughes 2017 Fred Hutchinson Cancer Research Center

Adaptive Non-Inferiority Margins Under Observable Non-Constancy, Brett S. Hanscom, Deborah J. Donnell, Brian D. Williamson, Jim Hughes

UW Biostatistics Working Paper Series

A central assumption in the design and conduct of non-inferiority trials is that the active-control therapy will have the same degree of effectiveness in the planned non-inferiority trial as it had in the prior placebo-controlled trials used to define the non-inferiority margin. This is referred to as the `constancy' assumption. If the constancy assumption fails, the chosen non-inferiority margin is not valid and the study runs the risk of approving an inferior product or failing to approve a beneficial product. The constancy assumption cannot be validated in a trial without a placebo arm, and it is unlikely ever to be ...


Calculating Power By Bootstrap, With An Application To Cluster-Randomized Trials, Ken Kleinman, Susan S. Huang 2017 University of Massachusetts Amherst, School of Public Health and Health Sciences

Calculating Power By Bootstrap, With An Application To Cluster-Randomized Trials, Ken Kleinman, Susan S. Huang

eGEMs (Generating Evidence & Methods to improve patient outcomes)

Background: A key requirement for a useful power calculation is that the calculation mimic the data analysis that will be performed on the actual data, once it is observed. Close approximations may be difficult to achieve using analytic solutions, however, and thus Monte Carlo approaches, including both simulation and bootstrap resampling, are often attractive. One setting in which this is particularly true is cluster-randomized trial designs. However, Monte Carlo approaches are useful in many additional settings as well. Calculating power for cluster-randomized trials using analytic or simulation-based methods is frequently unsatisfactory due to the complexity of the data analysis methods ...


It's All About Balance: Propensity Score Matching In The Context Of Complex Survey Data, David Lenis, Trang Q. ;Nguyen, Nian Dong, Elizabeth A. Stuart 2017 Department of Biostatistics, Johns Hopkins Bloomberg School of Public Health

It's All About Balance: Propensity Score Matching In The Context Of Complex Survey Data, David Lenis, Trang Q. ;Nguyen, Nian Dong, Elizabeth A. Stuart

Johns Hopkins University, Dept. of Biostatistics Working Papers

Many research studies aim to draw causal inferences using data from large, nationally representative survey samples, and many of these studies use propensity score matching to make those causal inferences as rigorous as possible given the non-experimental nature of the data. However, very few applied studies are careful about incorporating the survey design with the propensity score analysis, which may mean that the results don’t generate population inferences. This may be because few methodological studies examine how to best combine these methods. Furthermore, even fewer of the methodological studies incorporate different non-response mechanisms in their analysis. This study examines ...


Review Of: Daniel M. Kammen & David M. Hassenzahl, Should We Risk It: Exploring Environmental, Health, And Technological Problem Solving, Christopher Verni 2017 University of New Hampshire

Review Of: Daniel M. Kammen & David M. Hassenzahl, Should We Risk It: Exploring Environmental, Health, And Technological Problem Solving, Christopher Verni

RISK: Health, Safety & Environment

A review of the book Should We Risk It: Exploring Environmental, Health, and Technological Problem Solving by Daniel M. Kammen & David M. Hassenzahl, (Princeton University Press 1999). Preface, acknowledgments, introduction, appendix, index. ISBN: 0-691-00426-9 [404 pp. $39.50. Cloth, 41 William Street, Princeton, NJ 08540].


The Battle Against Malaria: A Teachable Moment, Randy K. Schwartz 2017 Schoolcraft College

The Battle Against Malaria: A Teachable Moment, Randy K. Schwartz

Journal of Humanistic Mathematics

Malaria has been humanity’s worst public health problem throughout recorded history. Mathematical methods are needed to understand which factors are relevant to the disease and to develop counter-measures against it. This article and the accompanying exercises provide examples of those methods for use in lower- or upper-level courses dealing with probability, statistics, or population modeling. These can be used to illustrate such concepts as correlation, causation, conditional probability, and independence. The article explains how the apparent link between sickle cell trait and resistance to malaria was first verified in Uganda using the chi-squared probability distribution. It goes on to ...


Moneyball For Creative Writers: A Statistical Strategy For Publishing Your Work, Jon Wesick 2017 Claremont Colleges

Moneyball For Creative Writers: A Statistical Strategy For Publishing Your Work, Jon Wesick

Journal of Humanistic Mathematics

Writers face a challenge getting their poems and stories published. Rather than following the traditional strategy I model creative writing submission as a statistical process and explore the use of numerical metrics to maximize publications.


Data Predictive Control For Building Energy Management, Achin Jain, Madhur Behl, Rahul Mangharam 2017 University of Pennsylvania

Data Predictive Control For Building Energy Management, Achin Jain, Madhur Behl, Rahul Mangharam

Real-Time and Embedded Systems Lab (mLAB)

Decisions on how to best optimize energy systems operations are becoming ever so complex and conflicting, that model-based predictive control (MPC) algorithms must play an important role. However, a key factor prohibiting the widespread adoption of MPC in buildings, is the cost, time, and effort associated with learning first-principles based dynamical models of the underlying physical system. This paper introduces an alternative approach for implementing finite-time receding horizon control using control-oriented data-driven models. We call this approach Data Predictive Control (DPC). Specifically, by utilizing separation of variables, two novel algorithms for implementing DPC using a single regression tree and with ...


Estimating The Probability Of Clonal Relatedness Of Pairs Of Tumors In Cancer Patients, Audrey Mauguen, Venkatraman E. Seshan, Irina Ostrovnaya, Colin B. Begg 2017 Memorial Sloan-Kettering Cancer Center

Estimating The Probability Of Clonal Relatedness Of Pairs Of Tumors In Cancer Patients, Audrey Mauguen, Venkatraman E. Seshan, Irina Ostrovnaya, Colin B. Begg

Memorial Sloan-Kettering Cancer Center, Dept. of Epidemiology & Biostatistics Working Paper Series

Next generation sequencing panels are being used increasingly in cancer research to study tumor evolution. A specific statistical challenge is to compare the mutational profiles in different tumors from a patient to determine the strength of evidence that the tumors are clonally related, i.e. derived from a single, founder clonal cell. The presence of identical mutations in each tumor provides evidence of clonal relatedness, although the strength of evidence from a match is related to how commonly the mutation is seen in the tumor type under investigation. This evidence must be weighed against the evidence in favor of independent ...


2014 Reporting Of Sexual Assault: Institutional Comparisons, M. E. Karns 2017 Cornell University

2014 Reporting Of Sexual Assault: Institutional Comparisons, M. E. Karns

Research Studies and Reports

Institutions of higher education are required to submit annual reports of sexual assault crimes to the Department of Education under the Clery Act. The Department of Education makes this data publicly available. Two primary measures are used to assess reporting of assault on campus: the Assault Reporting Ratio (ARR) and the Reporting Rate per 10,000 students (R10K). These measures are easily calculated and can be used to assess practices and policies that impact the reporting of sexual assault on campus.

The ARR and R10K are rate comparisons, a method widely used in public health. These rate comparisons measure how ...


Predicting Future Years Of Life, Health, And Functional Ability: A Healthy Life Calculator For Older Adults, Paula Diehr, Michael Diehr, Alice M. Arnold, Laura Yee, Michelle C. Odden, Calvin H. Hirsch, Stephen Thielke, Bruce Psaty, W Craig Johnson, Jorge Kizer, Anne B. Newman 2017 University of Washington

Predicting Future Years Of Life, Health, And Functional Ability: A Healthy Life Calculator For Older Adults, Paula Diehr, Michael Diehr, Alice M. Arnold, Laura Yee, Michelle C. Odden, Calvin H. Hirsch, Stephen Thielke, Bruce Psaty, W Craig Johnson, Jorge Kizer, Anne B. Newman

UW Biostatistics Working Paper Series

Introduction

Planning for the future would be easier if we knew how long we will live and, more importantly, how many years we will be healthy and able to enjoy it. There are few well-documented aids for predicting our future health. We attempted to meet this need for persons 65 years of age and older.

Methods

Data came from the Cardiovascular Health Study, a large longitudinal study of older adults that began in 1990. Years of life (YOL) were defined by measuring time to death. Years of healthy life (YHL) were defined by an annual question about self-rated health, and ...


Time Series Copulas For Heteroskedastic Data, Michael S. Smith, Worapree Maneesoonthorn, Ruben Loaiza-Maya 2017 Melbourne Business School

Time Series Copulas For Heteroskedastic Data, Michael S. Smith, Worapree Maneesoonthorn, Ruben Loaiza-Maya

Michael Stanley Smith

We propose parametric copulas that capture serial dependence in stationary heteroskedastic time series. We develop our copula for first order Markov series, and extend it to higher orders and multivariate series. We derive the copula of a volatility proxy, based on which we propose new measures of volatility dependence, including co-movement and spillover in multivariate series. In general, these depend upon the marginal distributions of the series. Using exchange rate returns, we show that the resulting copula models can capture their marginal distributions more accurately than univariate and multivariate GARCH models, and produce more accurate value at risk forecasts.


Estimating Time-Varying Effective Connectivity In High-Dimensional Fmri Data Using Regime-Switching Factor Models.Pdf, Chee-Ming Ting PhD, Hernando Ombao, S. Balqis Samdin, Sh-Hussain Salleh 2017 University of California - Irvine

Estimating Time-Varying Effective Connectivity In High-Dimensional Fmri Data Using Regime-Switching Factor Models.Pdf, Chee-Ming Ting Phd, Hernando Ombao, S. Balqis Samdin, Sh-Hussain Salleh

Chee-Ming Ting PhD

Recent studies on analyzing dynamic brain connectivity rely on sliding-window analysis or time-varying coefficient models which are unable to capture both smooth and abrupt changes simultaneously. Emerging evidence suggests state-related changes in brain connectivity where dependence structure alternates between a finite number of latent states or regimes. Another challenge is inference of full-brain networks with large number of nodes. We employ a Markov-switching dynamic factor model in which the state-driven time-varying connectivity regimes of high-dimensional fMRI data are characterized by lower-dimensional common latent factors, following a regime-switching process. It enables a reliable, data-adaptive estimation of change-points of connectivity regimes and ...


A Comparison Of The Quality Of Informed Consent For Clinical Trials Of An Experimental Hookworm Vaccine Conducted In Developed And Developing Countries., David J. Diemert, Lucas Lobato, Ashley Styczynski, Maria Zumer, Amanda Soares, Maria Flávia Gazzinelli 2017 George Washington University

A Comparison Of The Quality Of Informed Consent For Clinical Trials Of An Experimental Hookworm Vaccine Conducted In Developed And Developing Countries., David J. Diemert, Lucas Lobato, Ashley Styczynski, Maria Zumer, Amanda Soares, Maria Flávia Gazzinelli

Microbiology, Immunology, and Tropical Medicine Faculty Publications

Informed consent is one of the principal ethical requirements of conducting clinical research, regardless of the study setting. Breaches in the quality of the informed consent process are frequently described in reference to clinical trials conducted in developing countries, due to low levels of formal education, a lack of familiarity with biomedical research, and limited access to health services in these countries. However, few studies have directly compared the quality of the informed consent process in developed and developing countries using the same tool and in similar clinical trials. This study was conducted to compare the quality of the informed ...


The Spatial Dimensions Of State Fiscal Capacity The Mechanisms Of International Influence On Domestic Extractive Efforts, Cameron G. Thies, Olga Chyzh, Mark David Nieman 2017 Arizona State University

The Spatial Dimensions Of State Fiscal Capacity The Mechanisms Of International Influence On Domestic Extractive Efforts, Cameron G. Thies, Olga Chyzh, Mark David Nieman

Mark David Nieman

This paper expands traditional predatory theory approaches to state fiscal capacity by adopting spatial analytical reasoning and methods. While previous work in the predatory theory tradition has often incorporated interdependent external influences, such as war and trade, it has often done so in a way that maintains a theoretical and empirical autonomy of the state. Theoretically, we suggest four mechanisms (coercion, competition, learning, and emulation) that operate to channel information through interstate rivalry and territorial contiguity, trade networks, and the political space associated with regime type and intergovernmental organization membership. We test our predictions using a multi-parametric spatio-temporal autoregressive model ...


Quantifying The Totality Of Treatment Effect With Multiple Event-Time Observations In The Presence Of A Terminal Event From A Comparative Clinical Study, Brian Claggett, Lu Tian, Haoda Fu, Scott D. Solomon, L. J. Wei 2017 Harvard Medical School

Quantifying The Totality Of Treatment Effect With Multiple Event-Time Observations In The Presence Of A Terminal Event From A Comparative Clinical Study, Brian Claggett, Lu Tian, Haoda Fu, Scott D. Solomon, L. J. Wei

Harvard University Biostatistics Working Paper Series

To evaluate the totality of one treatment's benefit/risk profile relative to an alternative treatment via a longitudinal comparative clinical study, the timing and occurrence of multiple clinical events are typically collected during the patient's followup. These multiple observations reflect the patient's disease progression/burden over time. The standard practice is to create a composite endpoint from the multiple outcomes, the timing of the occurrence of the first clinical event, to evaluate the treatment via the standard survival analysis techniques. By ignoring all events after the composite outcome, this type of assessment may not be ideal. Various ...


The Finney County, Kansas Community Assessment Process: Fact Book, Debra J. Bolton PhD, Shannon L. Dick M.S. 2017 Kansas State University

The Finney County, Kansas Community Assessment Process: Fact Book, Debra J. Bolton Phd, Shannon L. Dick M.S.

Dr. Debra Bolton

This multi-lingual/multi-cultural study was called, Community Assets Processt, by the groups that “commissioned” it: Finnup Foundation, Finney County K-State Research & Extension, Western Kansas Community Foundation, Finney County United Way, Finney County Health Department, United Methodist Community Health Center (UMMAM), Center for Children and Families, Garden City Recreation Commission, and the Garden City Cultural Relations Board, because we intend for this to be an ongoing discussion. An objective, for those promoting the study, was to connect foundation, state, and federal funding with activities or services that addressed the true needs of people living in Finney County. The group was looking for data that would offer insights on ways to address the needs of diverse audiences through human services agencies, County Extension, the schools, churches, and other entities working with community members of Finney County. Initially, an online survey was sent to directors of Finney County’s human service organization/agencies and schools. Directors were asked what sorts of data were required to help them quantify the needs of their client/customer bases. It was from those responses that the committee designed the survey instrument. The objective of the resulting survey instrument was to gather data that would: Identify resources available in Finney County (a Minority-majority county) Identify services needed in the community Capture information regarding well-being of people in Finney County Feature General Demographic (gender, age, race/ethnicity, education, household income) Length of years lived in Finney County Primary and secondary languages spoken at home (the survey was conducted in four (4) languages) Educational needs Health questions (insurance, health conditions, mental health, medical care, etc.) Social and health needs; and Questions to measure community engagement and social involvement Target individuals and groups of varying ages, socio-economic backgrounds, ethnic backgrounds, and religious affiliations. Target survey respondents 18 years or older Keep survey respondents’ identities confidential since the study was approved by Kansas State University’s Institutional Review Board for compliance in Research with Human Subjects. Data were gathered from about 1% of Finney County’s population through surveys and focus groups conducted in four languages better to understand the ...


Consistency Of Cheeger And Ratio Graph Cuts, Nicolas Garcia Trillos, Dejan Slepcev, James von Brecht, Thomas Laurent, Xavier Bresson 2017 Loyola Marymount University

Consistency Of Cheeger And Ratio Graph Cuts, Nicolas Garcia Trillos, Dejan Slepcev, James Von Brecht, Thomas Laurent, Xavier Bresson

Thomas Laurent

This paper establishes the consistency of a family of graph-cut- based algorithms for clustering of data clouds. We consider point clouds obtained as samples of a ground-truth measure. We investigate approaches to clustering based on minimizing objective functionals defined on proximity graphs of the given sample. Our focus is on functionals based on graph cuts like the Cheeger and ratio cuts. We show that minimizers of these cuts converge as the sample size increases to a minimizer of a corresponding continuum cut (which partitions the ground truth measure). Moreover, we obtain sharp conditions on how the connectivity radius can be ...


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