Using a Quasi-Experimental Design in Combination with Multivariate Analysis to Assess Student Learning
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APPLICATION of the TAGUCHI METHOD to SENSITIVITY ANALYSIS of a MIDDLE- EAR FINITE-ELEMENT MODEL Li Qi1, Chadia S
APPLICATION OF THE TAGUCHI METHOD TO SENSITIVITY ANALYSIS OF A MIDDLE- EAR FINITE-ELEMENT MODEL Li Qi1, Chadia S. Mikhael1 and W. Robert J. Funnell1, 2 1 Department of BioMedical Engineering 2 Department of Otolaryngology McGill University Montréal, QC, Canada H3A 2B4 ABSTRACT difference in the model output due to the change in the input variable is referred to as the sensitivity. The Sensitivity analysis of a model is the investigation relative importance of parameters is judged based on of how outputs vary with changes of input parameters, the magnitude of the calculated sensitivity. The OFAT in order to identify the relative importance of method does not, however, take into account the parameters and to help in optimization of the model. possibility of interactions among parameters. Such The one-factor-at-a-time (OFAT) method has been interactions mean that the model sensitivity to one widely used for sensitivity analysis of middle-ear parameter can change depending on the values of models. The results of OFAT, however, are unreliable other parameters. if there are significant interactions among parameters. Alternatively, the full-factorial method permits the This paper incorporates the Taguchi method into the analysis of parameter interactions, but generally sensitivity analysis of a middle-ear finite-element requires a very large number of simulations. This can model. Two outputs, tympanic-membrane volume be impractical when individual simulations are time- displacement and stapes footplate displacement, are consuming. A more practical approach is the Taguchi measured. Nine input parameters and four possible method, which is commonly used in industry. It interactions are investigated for two model outputs. -
Introduction to Social Statistics
SOCY 3400: INTRODUCTION TO SOCIAL STATISTICS MWF 11-12:00; Lab PGH 492 (sec. 13748) M 2-4 or (sec. 13749)W 2-4 Professor: Jarron M. Saint Onge, Ph.D. Office: PGH 489 Phone: (713) 743-3962 Email: [email protected] Office Hours: MW 10-11 (Please email) or by appointment Teaching Assistant: TA Email: Office Hours: TTh 10-12 or by appointment Required Text: McLendon, M. K. 2004. Statistical Analysis in the Social Sciences. Additional materials will be distributed through WebCT COURSE DESCRIPTION: Sociological research relies on experience with both qualitative (e.g. interviews, participant observation) and quantitative methods (e.g., statistical analyses) to investigate social phenomena. This class focuses on learning quantitative methods for furthering our knowledge about the world around us. This class will help students in the social sciences to gain a basic understanding of statistics, whether to understand, critique, or conduct social research. The course is divided into three main sections: (1) Descriptive Statistics; (2) Inferential Statistics; and (3) Applied Techniques. Descriptive statistics will allow you to summarize and describe data. Inferential Statistics will allow you to make estimates about a population (e.g., this entire class) based on a sample (e.g., 10 or 12 students in the class). The third section of the course will help you understand and interpret commonly used social science techniques that will help you to understand sociological research. In this class, you will learn concepts associated with social statistics. You will learn to understand and grasp the concepts, rather than only focusing on getting the correct answers. -
THE HISTORY and DEVELOPMENT of STATISTICS in BELGIUM by Dr
THE HISTORY AND DEVELOPMENT OF STATISTICS IN BELGIUM By Dr. Armand Julin Director-General of the Belgian Labor Bureau, Member of the International Statistical Institute Chapter I. Historical Survey A vigorous interest in statistical researches has been both created and facilitated in Belgium by her restricted terri- tory, very dense population, prosperous agriculture, and the variety and vitality of her manufacturing interests. Nor need it surprise us that the successive governments of Bel- gium have given statistics a prominent place in their affairs. Baron de Reiffenberg, who published a bibliography of the ancient statistics of Belgium,* has given a long list of docu- ments relating to the population, agriculture, industry, commerce, transportation facilities, finance, army, etc. It was, however, chiefly the Austrian government which in- creased the number of such investigations and reports. The royal archives are filled to overflowing with documents from that period of our history and their very over-abun- dance forms even for the historian a most diflScult task.f With the French domination (1794-1814), the interest for statistics did not diminish. Lucien Bonaparte, Minister of the Interior from 1799-1800, organized in France the first Bureau of Statistics, while his successor, Chaptal, undertook to compile the statistics of the departments. As far as Belgium is concerned, there were published in Paris seven statistical memoirs prepared under the direction of the prefects. An eighth issue was not finished and a ninth one * Nouveaux mimoires de I'Acadimie royale des sciences et belles lettres de Bruxelles, t. VII. t The Archives of the kingdom and the catalogue of the van Hulthem library, preserved in the Biblioth^que Royale at Brussells, offer valuable information on this head. -
Precept 8: Some Review, Heteroskedasticity, and Causal Inference Soc 500: Applied Social Statistics
Precept 8: Some review, heteroskedasticity, and causal inference Soc 500: Applied Social Statistics Alex Kindel Princeton University November 15, 2018 Alex Kindel (Princeton) Precept 8 November 15, 2018 1 / 27 Learning Objectives 1 Review 1 Calculating error variance 2 Interaction terms (common support, main effects) 3 Model interpretation ("increase", "intuitively") 4 Heteroskedasticity 2 Causal inference with potential outcomes 0Thanks to Ian Lundberg and Xinyi Duan for material and ideas. Alex Kindel (Princeton) Precept 8 November 15, 2018 2 / 27 Calculating error variance We have some data: Y, X, Z. We think the correct model is Y = X + Z + u. We estimate this conditional expectation using OLS: Y = β0 + β1X + β2Z We want to know the standard error of β1. Standard error of β1 r ^2 ^ 1 σu 2 2 SE(βj ) = 2 Pn 2 , where Rj is the R of a regression of 1−Rj i=1(xij −x¯j ) variable j on all others. ^2 Question: What is σu? Alex Kindel (Princeton) Precept 8 November 15, 2018 3 / 27 Calculating error variance P 2 ^2 i u^i σu = DFresid You can adjust this in finite samples by u¯^ (why?) Alex Kindel (Princeton) Precept 8 November 15, 2018 4 / 27 Interaction terms Y = β0 + β1X + β2Z + β3XZ Assume X ∼ N (?; ?) and Z 2 f0; 1g Alex Kindel (Princeton) Precept 8 November 15, 2018 5 / 27 Interaction terms Y = β0 + β1X + β2Z + β3XZ Scenario 1 When Z = 0, X ∼ N (3; 4) When Z = 1, X ∼ N (−3; 2) Do you think an interaction term is justified here? Alex Kindel (Princeton) Precept 8 November 15, 2018 6 / 27 Interaction terms Y = β0 + β1X + β2Z + β3XZ Scenario -
How Differences Between Online and Offline Interaction Influence Social
Available online at www.sciencedirect.com ScienceDirect Two social lives: How differences between online and offline interaction influence social outcomes 1 2 Alicea Lieberman and Juliana Schroeder For hundreds of thousands of years, humans only Facebook users,75% ofwhom report checking the platform communicated in person, but in just the past fifty years they daily [2]. Among teenagers, 95% report using smartphones have started also communicating online. Today, people and 45%reportbeingonline‘constantly’[2].Thisshiftfrom communicate more online than offline. What does this shift offline to online socializing has meaningful and measurable mean for human social life? We identify four structural consequences for every aspect of human interaction, from differences between online (versus offline) interaction: (1) fewer how people form impressions of one another, to how they nonverbal cues, (2) greater anonymity, (3) more opportunity to treat each other, to the breadth and depth of their connec- form new social ties and bolster weak ties, and (4) wider tion. The current article proposes a new framework to dissemination of information. Each of these differences identify, understand, and study these consequences, underlies systematic psychological and behavioral highlighting promising avenues for future research. consequences. Online and offline lives often intersect; we thus further review how online engagement can (1) disrupt or (2) Structural differences between online and enhance offline interaction. This work provides a useful offline interaction -
A Meta-Analysis Examining the Impact of Computer-Assisted Instruction on Postsecondary Statistics Education: 40 Years of Research JRTE | Vol
A Meta-Analysis Examining the Impact of Computer-Assisted Instruction on Postsecondary Statistics Education: 40 Years of Research JRTE | Vol. 43, No. 3, pp. 253–278 | ©2011 ISTE | iste.org A Meta-Analysis Examining the Impact of Computer-Assisted Instruction on Postsecondary Statistics Education: 40 Years of Research Karen Larwin Youngstown State University David Larwin Kent State University at Salem Abstract The present meta-analysis is a comprehensive investigation of the effectiveness of computer-assisted instruction (CAI) on student achievement in postsec- ondary statistics education across a forty year period of time. The researchers calculated an overall effect size of 0.566 from 70 studies, for a total of 219 effect-size measures from a sample of n = 40,125 participants. These results suggest that the typical student moved from the 50th percentile to the 73rd percentile when technology was used as part of the curriculum. This study demonstrates that subcategories can further the understanding of how the use of CAI in statistics education might be maximized. The study discusses im- plications and limitations. (Keywords: statistics education, computer-assisted instruction, meta-analysis) iscovering how students learn most effectively is one of the major goals of research in education. During the last 30 years, many re- Dsearchers and educators have called for reform in the area of statistics education in an effort to more successfully reach the growing population of students, across an expansive variety of disciplines, who are required to complete coursework in statistics (e.g., Cobb, 1993, 2007; Garfield, 1993, 1995, 2002; Giraud, 1997; Hogg, 1991; Lindsay, Kettering, & Siegmund, 2004; Moore, 1997; Roiter, & Petocz, 1996; Snee, 1993;Yilmaz, 1996). -
ARIADNE (Axion Resonant Interaction Detection Experiment): an NMR-Based Axion Search, Snowmass LOI
ARIADNE (Axion Resonant InterAction Detection Experiment): an NMR-based Axion Search, Snowmass LOI Andrew A. Geraci,∗ Aharon Kapitulnik, William Snow, Joshua C. Long, Chen-Yu Liu, Yannis Semertzidis, Yun Shin, and Asimina Arvanitaki (Dated: August 31, 2020) The Axion Resonant InterAction Detection Experiment (ARIADNE) is a collaborative effort to search for the QCD axion using techniques based on nuclear magnetic resonance. In the experiment, axions or axion-like particles would mediate short-range spin-dependent interactions between a laser-polarized 3He gas and a rotating (unpolarized) tungsten source mass, acting as a tiny, fictitious magnetic field. The experiment has the potential to probe deep within the theoretically interesting regime for the QCD axion in the mass range of 0.1- 10 meV, independently of cosmological assumptions. In this SNOWMASS LOI, we briefly describe this technique which covers a wide range of axion masses as well as discuss future prospects for improvements. Taken together with other existing and planned axion experi- ments, ARIADNE has the potential to completely explore the allowed parameter space for the QCD axion. A well-motivated example of a light mass pseudoscalar boson that can mediate new interactions or a “fifth-force” is the axion. The axion is a hypothetical particle that arises as a consequence of the Peccei-Quinn (PQ) mechanism to solve the strong CP problem of quantum chromodynamics (QCD)[1]. Axions have also been well motivated as a dark matter candidatedue to their \invisible" nature[2]. Axions can couple to fundamental fermions through a scalar vertex and a pseudoscalar vertex with very weak coupling strength. -
Uses for Census Data in Market Research
Uses for Census Data in Market Research MRS Presentation 4 July 2011 Andrew Zelin, Director, Sampling & RMC, Ipsos MORI Why Census Data is so critical to us Use of Census Data underlies almost all of our quantitative work activities and projects Needed to ensure that: – Samples are balanced and representative – ie Sampling; – Results derived from samples reflect that of target population – ie Weighting; – Understanding how demographic and geographic factors affect the findings from surveys – ie Analysis. How would we do our jobs without the use of Census Data? Our work withoutCensusData Our work Regional Assembly What I will cover Introduction, overview and why Census Data is so critical; Census data for sampling; Census data for survey weighting; Census data for statistical analysis; Use of SARs; The future (eg use of “hypercubes”); Our work without Census Data / use of alternatives; Conclusions Census Data for Sampling For Random (pre-selected) Samples: – Need to define stratum sample sizes and sampling fractions; – Need to define cluster size, esp. if PPS – (Need to define stratum / cluster) membership; For any type of Sample: – To balance samples across demographics that cannot be included as quota controls or stratification variables – To determine number of sample points by geography – To create accurate booster samples (eg young people / ethnic groups) Census Data for Sampling For Quota (non-probability) Samples: – To set appropriate quotas (based on demographics); Data are used here at very localised level – ie Census Outputs Census Data for Sampling Census Data for Survey Weighting To ensure that the sample profile balances the population profile Census Data are needed to tell you what the population profile is ….and hence provide accurate weights ….and hence provide an accurate measure of the design effect and the true level of statistical reliability / confidence intervals on your survey measures But also pre-weighting, for interviewer field dept. -
Report on Exact and Statistical Matching Techniques
Statistical Policy Working Papers are a series of technical documents prepared under the auspices of the Office of Federal Statistical Policy and Standards. These documents are the product of working groups or task forces, as noted in the Preface to each report. These Statistical Policy Working Papers are published for the purpose of encouraging further discussion of the technical issues and to stimulate policy actions which flow from the technical findings and recommendations. Readers of Statistical Policy Working Papers are encouraged to communicate directly with the Office of Federal Statistical Policy and Standards with additional views, suggestions, or technical concerns. Office of Joseph W. Duncan Federal Statistical Director Policy Standards For sale by the Superintendent of Documents, U.S. Government Printing Office Washington, D.C. 20402 Statistical Policy Working Paper 5 Report on Exact and Statistical Matching Techniques Prepared by Subcommittee on Matching Techniques Federal Committee on Statistical Methodology DEPARTMENT OF COMMERCE UNITED STATES OF AMERICA U.S. DEPARTMENT OF COMMERCE Philip M. Klutznick Courtenay M. Slater, Chief Economist Office of Federal Statistical Policy and Standards Joseph W. Duncan, Director Issued: June 1980 Office of Federal Statistical Policy and Standards Joseph W. Duncan, Director Katherine K. Wallman, Deputy Director, Social Statistics Gaylord E. Worden, Deputy Director, Economic Statistics Maria E. Gonzalez, Chairperson, Federal Committee on Statistical Methodology Preface This working paper was prepared by the Subcommittee on Matching Techniques, Federal Committee on Statistical Methodology. The Subcommittee was chaired by Daniel B. Radner, Office of Research and Statistics, Social Security Administration, Department of Health and Human Services. Members of the Subcommittee include Rich Allen, Economics, Statistics, and Cooperatives Service (USDA); Thomas B. -
Propensity Scores up to Head(Propensitymodel) – Modify the Number of Threads! • Inspect the PS Distribution Plot • Inspect the PS Model
Overview of the CohortMethod package Martijn Schuemie CohortMethod is part of the OHDSI Methods Library Cohort Method Self-Controlled Case Series Self-Controlled Cohort IC Temporal Pattern Disc. Case-control New-user cohort studies using Self-Controlled Case Series A self-controlled cohort A self-controlled design, but Case-control studies, large-scale regressions for analysis using fews or many design, where times preceding using temporals patterns matching controlss on age, propensity and outcome predictors, includes splines for exposure is used as control. around other exposures and gender, provider, and visit models age and seasonality. outcomes to correct for time- date. Allows nesting of the Estimation methods varying confounding. study in another cohort. Patient Level Prediction Feature Extraction Build and evaluate predictive Automatically extract large models for users- specified sets of featuress for user- outcomes, using a wide array specified cohorts using data in of machine learning the CDM. Prediction methods algorithms. Empirical Calibration Method Evaluation Use negative control Use real data and established exposure-outcomes pairs to reference sets ass well as profile and calibrate a simulations injected in real particular analysis design. data to evaluate the performance of methods. Method characterization Database Connector Sql Render Cyclops Ohdsi R Tools Connect directly to a wide Generate SQL on the fly for Highly efficient Support tools that didn’t fit range of databases platforms, the various SQLs dialects. implementations of regularized other categories,s including including SQL Server, Oracle, logistic, Poisson and Cox tools for maintaining R and PostgreSQL. regression. libraries. Supporting packages Under construction Technologies CohortMethod uses • DatabaseConnector and SqlRender to interact with the CDM data – SQL Server – Oracle – PostgreSQL – Amazon RedShift – Microsoft APS • ff to work with large data objects • Cyclops for large scale regularized regression Graham study steps 1. -
CORRELATION COEFFICIENTS Ice Cream and Crimedistribute Difficulty Scale ☺ ☺ (Moderately Hard)Or
5 COMPUTING CORRELATION COEFFICIENTS Ice Cream and Crimedistribute Difficulty Scale ☺ ☺ (moderately hard)or WHAT YOU WILLpost, LEARN IN THIS CHAPTER • Understanding what correlations are and how they work • Computing a simple correlation coefficient • Interpretingcopy, the value of the correlation coefficient • Understanding what other types of correlations exist and when they notshould be used Do WHAT ARE CORRELATIONS ALL ABOUT? Measures of central tendency and measures of variability are not the only descrip- tive statistics that we are interested in using to get a picture of what a set of scores 76 Copyright ©2020 by SAGE Publications, Inc. This work may not be reproduced or distributed in any form or by any means without express written permission of the publisher. Chapter 5 ■ Computing Correlation Coefficients 77 looks like. You have already learned that knowing the values of the one most repre- sentative score (central tendency) and a measure of spread or dispersion (variability) is critical for describing the characteristics of a distribution. However, sometimes we are as interested in the relationship between variables—or, to be more precise, how the value of one variable changes when the value of another variable changes. The way we express this interest is through the computation of a simple correlation coefficient. For example, what’s the relationship between age and strength? Income and years of education? Memory skills and amount of drug use? Your political attitudes and the attitudes of your parents? A correlation coefficient is a numerical index that reflects the relationship or asso- ciation between two variables. The value of this descriptive statistic ranges between −1.00 and +1.00. -
Generalized Scatter Plots
Generalized scatter plots Daniel A. Keim a Abstract Scatter Plots are one of the most powerful and most widely used b techniques for visual data exploration. A well-known problem is that scatter Ming C. Hao plots often have a high degree of overlap, which may occlude a significant Umeshwar Dayal b portion of the data values shown. In this paper, we propose the general a ized scatter plot technique, which allows an overlap-free representation of Halldor Janetzko and large data sets to fit entirely into the display. The basic idea is to allow the Peter Baka ,* analyst to optimize the degree of overlap and distortion to generate the best possible view. To allow an effective usage, we provide the capability to zoom ' University of Konstanz, Universitaetsstr. 10, smoothly between the traditional and our generalized scatter plots. We iden Konstanz, Germany. tify an optimization function that takes overlap and distortion of the visualiza bHewlett Packard Research Labs, 1501 Page tion into acccount. We evaluate the generalized scatter plots according to this Mill Road, Palo Alto, CA94304, USA. optimization function, and show that there usually exists an optimal compro mise between overlap and distortion . Our generalized scatter plots have been ' Corresponding author. applied successfully to a number of real-world IT services applications, such as server performance monitoring, telephone service usage analysis and financial data, demonstrating the benefits of the generalized scatter plots over tradi tional ones. Keywords: scatter plot; overlapping; distortion; interpolation; smoothing; interactions Introduction Motivation Large amounts of multi-dimensional data occur in many important appli cation domains such as telephone service usage analysis, sales and server performance monitoring.