Research & expertise
Our team brings diversity and a breadth of skills, experiences, and perspectives to NWEA research.

Accessibility Research Manager
Elizabeth Barker began her career in education as a middle school and elementary special education teacher, specifically of students with mild-to-moderate disabilities in Michigan and Colorado. She received her doctoral degree with an emphasis on growth trajectories for students with learning disabilities in mathematics and reading comprehension from the University of Oregon. Her current research focuses on how growth trajectories vary among students with visual impairments, deafness and hearing loss, and other disabilities.
Collaborative for Student Growth
Topics: Equity, Accessibility, Growth modeling

Research Scientist
Helena Connolly is a learning scientist whose research focuses on math and science learning, non-routine problem solving, motivation, and teacher adaptivity. Helena primarily conducts experimental and mixed methods research with K-12 students and teachers. As a former elementary school teacher, Helena seeks to understand various pedagogical approaches and how they affect individual learners. Prior to joining NWEA, Helena explored these questions as a research fellow at the Institute for Learning Technologies at Teachers College, Columbia University, where she earned a PhD in cognitive science in education.
Academic Content
Topics: Early learning, Math & STEM, Middle school

Affiliated Research Scientist
John Cronin’s work focuses on helping teachers, administrators, and school board members improve their presentation and use of data in schools. He provides consultation related to testing issues and the use of data to the US Department of Education, Texas Association of School Administrators, New York State Council of School Superintendents, Confederation of Oregon School Administrators, and District Administration Leadership Institute.
Center for School and Student Progress
Topics: Student growth & accountability policies, Empowering educators

Manager, Research Reporting & Data Analytics
Michael Dahlin leads NWEA’s Reporting & Data Analytics team. He specializes in research and reporting on college readiness and school accountability policy. Before joining NWEA, he was a research analyst for the Oregon Department of Human Services. He holds a PhD in developmental psychology from Penn State.
Academic Content
Topics: Innovations in reporting & assessment, College & career readiness, Student growth & accountability policies

Research Scientist
Miles Davison specializes in using quantitative and mixed-methodologies to examine how K-12 intervention policies and programs impact equity in schools.
Center for School and Student Progress
Topics: Equity, COVID-19 & schools, Social-emotional learning

Research Scientist
Erin Fahle investigates how social and school context affects gender, racial/ethnic, and socioeconomic inequalities in student’s access to educational opportunities and subsequent achievement.
Collaborative for Student Growth
Topics: Equity, COVID-19 & schools, Student growth & accountability policies

Senior Research Scientist
Broadly, Michael Gaddis’s work provides evidence of inequality in the US related to race/ethnicity, social class, and education. He studies educational inequality across five dimensions: (1) the effects of educational credentials on important life outcomes, including employment and health; (2) when and how educational credentials attenuate or exacerbate racial/ethnic discrimination; (3) intergenerational mobility as it relates to the direct and indirect effects of educational attainment across generations; (4) differences in students’ mental health and campus-level stigma across college and universities and the subsequent impact on academic achievement and attainment; and (5) racial/ethnic and SES inequalities in cultural capital and social capital and their effects on academic achievement and attainment among K–12 students.
Collaborative for Student Growth

Learning and Assessment Engineer
As a learning and assessment engineer, Garron conducts research and development to optimize assessment systems for measuring student learning, engagement, and instructional utility. His recent research has focused on through-year assessment models, item difficulty models, and optimal design of longitudinal adaptive tests.
Measurement & Psychometrics
Topics: Test design, Computer adaptive testing, Learning standards & alignment

Manager, Measurement & Quantitative Sciences
Kim has conducted education research for over 10 years, focusing on the use of research to support student learning and addressing issues of equity and access. Her work began in policy research consulting, supporting the evaluation of school-based and adult education intervention initiatives. She continued in the public sector, having served as the lead evaluator of early learning programs in San Mateo County’s Office of Education (CA) and leading the research and analytics team responsible for data management, evaluation, and grant-funded development projects at Aspire Public Schools. Prior to NWEA, she was the research manager of product development and advanced analytics at DreamBox Learning, a gamified online learning platform for primary and secondary students in math and reading. She has a PhD in education (with a focus on quantitative research methods) from UCSB and has applied methodologies ranging from causal inference, psychometrics, as well as predictive and classification (ML) modeling in her work.
Academic Content

Research Scientist
Meg Guerreiro’s previous career as a teacher in the School District of Philadelphia is the foundation for her work to make assessments equitable and accessible for all students.
Academic Content
Topics: Equity, Accessibility, Innovations in reporting & assessment

Research Scientist
Ayesha K. Hashim uses interdisciplinary and mixed-methods research designs to study the impacts of district-level school policies on student learning, and the leadership, organizational, and implementation conditions that can explain observed results.
Collaborative for Student Growth
Topics: Equity, COVID-19 & schools, Student growth & accountability policies

Principal Research Scientist
Wei He develops innovative solutions to enhance existing products such as MAP Growth. Her research is focused on psychometrics, adaptive testing, educational accountability issues, and applied statistics. Her work has been published in peer-reviewed journals such as the Journal of Educational Measurement, Educational and Psychological Measurement, and the International Journal of Testing. She is also a frequent presenter at national and international conferences, including NCME, AERA, and IACAT. Dr. He’s publications and presentations cover diverse topics like CAT item selection and item pool design, item field testing and calibration, test equating, missing data treatment, and item equivalence in international assessments. She holds a PhD in measurement and quantitative methods from Michigan State University.
Measurement & Psychometrics
Topics: Measurement & scaling, Computer adaptive testing, Guidance, Item response theory

(1963 - 2020)
Andrew Hegedus consulted with education system leaders around the world; prototyped, launched, and supported state-of-the-art reports; and managed research projects focused on understanding the drivers for growth in schools with differing levels of challenges.
Center for School and Student Progress
Topics: Empowering educators, High-growth schools & practices

Kari Hodge manages the MAP Reading Fluency psychometric solutions team at NWEA. Her research interests include Rasch models, small sample equating, standard setting, and using psychometrics for data-driven decision making. Dr. Hodge has authored four book chapters and published more than 15 articles in peer-reviewed journals such as the Journal of Applied Measurement, Journal of Applied Testing Technology, and Educational and Psychological Measurement. Prior to joining NWEA, Dr. Hodge was an educator for more than 10 years with experience teaching elementary through doctoral-level courses. She brings to NWEA over 15 years of assessment development and psychometric experience. Dr. Hodge holds a PhD in Educational Psychology from Baylor University. She also holds a bachelor’s degree in education and an M.Ed. in Curriculum and Instruction.
Measurement & Psychometrics

Manager, Psychometric Solutions
Ann Hu works mainly on MAP Growth assessments. Her research interests include linking studies between formative and summative assessments, item bank development and maintenance, adaptive testing engines, test security, and norms studies. She has extensive experience in conducting psychometric analyses and research based on Rasch models and IRT, constructing fixed forms and CATs, and designing and conducting standard settings. Prior to joining NWEA in 2017, Dr. Hu worked at Data Recognition Corporation (DRC) on multiple large-scale achievement testing programs for Pennsylvania, Michigan, Oklahoma, Louisiana, Alabama, and Minnesota. Dr. Hu holds a doctorate in measurement, evaluation, and cognition from the University of Alberta. She also holds a bachelor’s degree in psychology and a MEd in educational psychology.
Measurement & Psychometrics
Topics: Measurement & scaling, Test design

Vice President of District Research
Nate Jensen specializes in issues related to the use of student testing data in accountability systems and its application to myriad policy decisions.
Center for School and Student Progress
Topics: Measurement & scaling, School & test engagement, Student growth & accountability policies

Research Scientist
Angela Johnson specializes in experimental, quasi-experimental, and mixed methods research designs. Her research focuses on identifying and reducing inequality.
Center for School and Student Progress
Topics: Equity, English Language Learners, Growth modeling

Research Scientist
Danny Katz is a research scientist focusing on the philosophy of measurement, ontology, and psychometrics. He is interested in methods for improving measurement claims in educational settings as well as using ideas from the philosophies of science and language to understand how we conceptualize what might be measurable in the human sciences. He hopes to do more work connecting educational measurement, psychometrics, and education policy. He has worked and published in areas related to test fairness, adolescent literacy, university-level biology education, and program evaluation. He is a PhD candidate at the University of California, Santa Barbara.
Academic Content

Senior Psychometrician
Jungnam Kim leads the psychometric work for the Nebraska Student-Centered Assessment System (NSCAS). Her research interests include equating, vertical scaling, and adaptive testing. Prior to joining NWEA in 2017, Dr. Kim worked at CTB/McGraw-Hill for over eight years, where she served as lead research scientist for various state assessment programs including the Georgia Criterion Referenced Competency Tests, Transitional Colorado Assessment Program, North Dakota State Assessments, Colorado Alternate Assessment, and Tests of Adult Basic Education. Dr. Kim holds a PhD in educational measurement from the University of Iowa.
Measurement & Psychometrics
Topics: Measurement & scaling, Computer adaptive testing, Item response theory

Affiliated Research Scientist
G. Gage Kingsbury provides advice and development work in the application of technology to practical assessment situations. He designed the first adaptive tests used in educational settings and helped design adaptive tests currently administered to K–12 students throughout the United States and in a wide variety of international schools.
Collaborative for Student Growth
Topics: Measurement & scaling, Innovations in reporting & assessment

Research Scientist
Gregory King uses quantitative methods to research college and career readiness, policies that impact higher education access and success, and the K–12 to higher education pipeline.
Academic Content
Topics: Innovations in reporting & assessment, College & career readiness

Senior Research Scientist
Susan Kowalski began her career in science education teaching high school physics and physical science in Bloomington, MN. She completed her PhD in curriculum and instruction from the University of Minnesota and the spent several years developing and researching curricula and professional learning experiences at BSCS Science Learning. Her current work investigates new approaches to three-dimensional assessment in support of the Next Generation Science Standards. She is focused on how teachers might learn to more effectively use assessment data to inform their day-to-day science instruction and enhance equitable learning opportunities for students.
Academic Content
Topics: Innovations in reporting & assessment, Empowering educators, Math & STEM

Senior Research Scientist
Megan Kuhfeld seeks to understand students’ trajectories of academic and social-emotional learning and the school and neighborhood influences that promote optimal growth.
Collaborative for Student Growth
Topics: Measurement & scaling, Growth modeling, Seasonal learning patterns & summer loss

Research Scientist
Meredith Langi specializes in educational measurement and latent variable modeling and is particularly interested in how assessments can support classroom instruction. Prior to joining NWEA, Dr. Langi supported psychometrics for the English Language Proficiency Assessment (ELPA21). She also served as a teacher and resource specialist with the Peace Corps in Tonga. Dr. Langi holds a PhD in social research methodology and an MS in statistics from the University of California, Los Angeles, as well as an EdM in international education policy from the Harvard Graduate School of Education.
Center for School and Student Progress
Topics: Measurement & scaling, Early learning, Growth modeling

Senior Research Scientist
Kat’s research interests include authentic, phenomenon-based learning experiences in science classrooms. She is especially interested in developing and using learning progressions to support and assess students’ competence with scientific practices, such as modeling and explaining scientific phenomena. Kat completed her PhD in chemistry and MA in educational measurement and statistics at the University of Iowa. Prior to joining NWEA, Kat worked in discipline-based education research, primarily in chemistry contexts, at San Diego State University and the University of Iowa.
Academic Content

Senior Psychometrician
Jonghwan (Jay) Lee leads NWEA’s adaptive constraint engine work for state summative assessments, including preparing the engine, running simulations, and validating and improving the engine’s performance. Dr. Lee’s research interests include subscore reporting, the impact of technology-enhanced items on student assessment performance, item pool management for computerized adaptive testing (CAT), and score compatibility on CAT across administrations. Prior to joining NWEA in 2017, he worked as a senior psychometrician at Questar Assessment, where he conducted all psychometric-related tasks for various state assessment programs including item analysis, calibration and equating, standard setting, psychometric guidelines for form construction, and the creation of annual technical reports. Dr. Lee holds a PhD in measurement and quantitative methods from Michigan State University and a bachelor’s degree in electrical computer engineering from the Ohio State University.
Measurement & Psychometrics

Director
Karyn Lewis is director of the Center for School and Student Progress at NWEA where she leads a team of researchers who operate at the intersection of K-12 education research, practice, and policy.
Center for School and Student Progress
Topics: School & test engagement, Social-emotional learning, Student growth & accountability policies

Senior Psychometrician
Xueming (Sylvia) Li focuses on psychometric issues related to MAP Growth. Her research interests include computer-based testing, applications of IRT, test validity, cross-cultural assessment, and test score linking and equating. Prior to joining NWEA in 2015, she received a doctoral degree in research, educational measurement, and psychometrics from the University of Massachusetts Amherst.
Measurement & Psychometrics
Topics: Measurement & scaling, Accessibility, Assessments in Spanish, Computer adaptive testing, Growth, Item response theory, Reading & language arts

Principal Scientist
Tyler Matta is motived to improve the tools used for educational decision making to support the building of equitable educational systems. His work spans computational psychometrics, learning theory, and education policy.
Academic Content
Topics: Measurement & scaling, Growth modeling, Innovations in reporting & assessment

Director
Andrew McEachin’s work focuses on helping policymakers and educators make informed decisions about the design and implementation of educational policies, so that data and policies may better support student learning and more equitable opportunities and outcomes for all students.
Collaborative for Student Growth
Topics: Equity, Seasonal learning patterns & summer loss, Student growth & accountability policies

Senior Director, Psychometric Solutions
Patrick Meyer manages the team of psychometricians, statistical analysts, and project managers involved in the district division of NWEA. This team conducts psychometric research for assessments such as MAP Growth and MAP Reading Fluency. His research interests include IRT, psychometric software design, and the psychometric characteristics of teaching measures. Dr. Meyer is the inventor and lead developer of jMetrik, an open-source software program used in over 20 countries. He has authored two books and published over 20 articles in peer-reviewed journals such as the Journal of Educational Measurement, Applied Psychological Measurement, and Educational and Psychological Measurement. He has conducted 25 standard-setting workshops in the licensure and certification field, as well as numerous workshops on psychometric theory and the use of jMetrik for data analysis. Prior to joining NWEA in 2018, Dr. Meyer worked as an associate professor with tenure in the Curry School of Education at the University of Virginia, where he taught courses in educational measurement and applied statistics. He began his academic career in 2004 as an assistant professor at James Madison University’s Center for Assessment and Research Studies. Dr. Meyer holds a PhD in educational psychology and research from the University of South Carolina.
Measurement & Psychometrics
Topics: Measurement & scaling, Assessments in Spanish, Computer adaptive testing, Guidance, Item response theory, Test design

Research Scientist
Emily Morton specializes in using quantitative methodologies to examine academic and developmental impacts of policies and programs on students. Her research interests center around estimating the effects of K-12 education policies and programs related to school schedules, instructional time, and learning environments on student achievement and youth development, and understanding the processes involved in promoting positive youth and human development across the lifespan.
Center for School and Student Progress
Topics: COVID-19 & schools, Middle school, Social-emotional learning

Research Scientist
Colleen Oppenzato’s research focuses on how students develop mathematical thinking, from early childhood through the middle grades. Her specific interests include children’s understanding of rational numbers, how textbook input affects student learning, and how to measure teachers’ math pedagogical content knowledge. She is currently completing her PhD in cognitive science in education at Teachers College. Prior to joining NWEA, Colleen worked as an elementary school and middle school special education teacher and then as a math curriculum developer, editor, and project manager. She was also an affiliate with the Development and Research in Early Math Education (DREME) Network, where she created materials for teacher educators and for family math activities.
Academic Content

Psychometrician
Fang Peng works with the MAP Reading Fluency assessment. Among her interests and areas of expertise are computerized adaptive testing, measurement validity, early childhood development, and applications of natural language processing and machine learning in assessment contexts. Prior to joining NWEA in 2022, Fang worked as a psychometrician at the National Council of State Boards of Nursing where she gained extensive operational and research experience in large-scale licensure examinations. Fang holds a PhD in Educational Psychology with a concentration in Measurement, Evaluation, Statistics, and Assessment from the University of Illinois at Chicago.
Measurement & Psychometrics

Senior Research Scientist
Scott J. Peters specializes in educational assessment and data use, gifted and talented student identification, equity within advanced educational opportunities, and effectiveness of educational policy.
Center for School and Student Progress
Topics: Equity, Empowering educators, Student growth & accountability policies

Research Engineer
Alexis Prijoles specializes in developing processes for data management. Before joining NWEA, she was a research specialist at the University of Virginia. She holds a BS in mathematical sciences from Clemson University and an MEd in Educational Psychology – Research, Statistics, and Evaluation from the University of Virginia.
Academic Content
Topics: Measurement & scaling, Empowering educators, Innovations in reporting & assessment

Senior Research Scientist
Erik Ruzek’s research focuses on how classroom and school processes shape student engagement, motivation, and learning. As an educational psychologist, his work emphasizes the measurement of students’ subjective experiences of their classrooms and school. He combines student-reported experiential data with classroom observations, teacher reports, and direct assessments to identify the essential features of teacher-student and student-peer interactions that engage and motivate students.
Academic Content
Topics: Social-emotional learning, Early learning, Middle school

Affiliated Research Scientist
James Soland’s research focuses on assessment and evaluation policy and practice. Particular areas of emphasis include measuring social-emotional learning (SEL), test engagement, and estimating teacher and school effectiveness.
Collaborative for Student Growth
Topics: Measurement & scaling, Social-emotional learning, Student growth & accountability policies

Research Scientist
Yon Soo Suh’s interests lie in developing and applying quantitative methods to promote more accurate modeling, interpretation, and use of educational data in assessment settings and empirical research. She specializes in latent variable modeling with a focus on understanding fine-grained psychological and cognitive processes underlying various response data. Prior to joining NWEA, Yon Soo worked with institutions such as the Smarter Balanced Assessment Consortium, PBS Kids, and the Korean Institution of Curriculum and Education while at UCLA CRESST. Her projects included psychometric analyses of large-scale assessment data, analysis of telemetry data from digital educational games, and scale development and validation. Yon Soo holds a PhD in education, focused on quantitative methods, and a master’s degree in statistics from the University of California, Los Angeles. She also received a master’s degree in education and a bachelor’s degree in English language and literature, along with a national teaching certificate for English, from Yonsei University in South Korea.
Academic Content

Executive VP of Research
Beth Tarasawa is relentlessly committed to using data-driven insights to transform education and eliminate structural barriers to achieve equitable outcomes for all students.
Center for School and Student Progress
Topics: Equity, Empowering educators, Student growth & accountability policies

Senior Research Scientist
Yeow Meng Thum focuses on methodological research on multivariate, multilevel models for behavioral and educational data, with a strong emphasis on methods for describing growth and change, as well as on topics in latent variable modeling, causal inference, and psychometrics.
Academic Content
Topics: Measurement & scaling, Growth modeling, Student growth & accountability policies

Senior Psychometrician
Shudong Wang focuses on product design and development, including psychometric development of MAP Reading Fluency and MAP Growth Spanish Reading. His research interests include adaptive testing and generalized linear mixed-model applications in educational measurement and psychometric research. Dr. Wang has published over 20 peer-reviewed journal articles and book chapters. He has presented at numerous conferences, including NCME, AERA, and CCSSO, on topics such as CAT item selection and quality of student scoring, effects of CAT designs on content coverage and efficiency, and accuracy of student ability estimations. Prior to joining NWEA in 2009, he was a senior psychometrician at ETS. Dr. Wang holds a PhD in educational research methodology from the University of Pittsburgh.
Measurement & Psychometrics
Topics: Measurement & scaling, Assessments in Spanish, Computer adaptive testing, Growth modeling, Item response theory, Learning standards & alignment, Reading & language arts, Test design

Research Scientist
Donny Williams is a research scientist with over five years of experience in advanced statistical methodology, including mixed models, causal inference and time series, meta-analysis, and Bayesian statistics. He specializes in developing statistical software for solving problems in the social-behavioral sciences. He is the author of 30 peer-reviewed publications, including high-impact work appearing in prestigious quantitative journals such as Psychological Methods and Multivariate Behavior Research. Donny is a PhD candidate in quantitative psychology at the University of California, Davis.
Academic Content
Topics: Growth modeling

Senior Research Scientist
Steven Wise has published extensively during the past three decades in applied measurement, with particular emphases in computer-based testing and the psychology of test taking.
Collaborative for Student Growth
Topics: School & test engagement, Innovations in reporting & assessment, Student growth & accountability policies

Psychometrician
Kang Xue works with the MAP Reading Fluency assessment. His research interest centers on the intersection of psychometrics, machine learning, data science, and artificial intelligence. His interdisciplinary background allows him to borrow some ideas from machine learning and apply them to psychometric models, such as IRT and CDM, with the hope of better handling complex assessment data. Dr. Xue joined NWEA in 2020 after obtaining a PhD in educational psychology from the University of Georgia. Dr. Xue holds another doctoral degree in electrical engineering, and he served as a senior research engineer at Samsung Advanced Institute of Technology (Advanced Technology Lab) from 2013 to 2015.
Measurement & Psychometrics
Topics: Measurement & scaling, Innovations in reporting & assessment