Research Team
The Pacific Metrics Research Team is comprised of a unique team of veteran professionals with extensive hands-on experience in assessment, education technologies, and psychometrics. Our psychometricians, education technologists, and researchers are some of the best in the industry, with a national reputation for sharing their knowledge and expertise in test development, administration, scoring, and reporting. Leading the team are Drs. E. Matthew Schulz and W. Alan Nicewander.
E. Matthew Schulz, Ph.D.
Director of Research
W. Alan Nicewander, Ph.D.
Chief Psychometrician
Susan Lottridge, Ph.D.
Technical Director, Machine Scoring
Dr. Schulz provides leadership on assessment development, psychometric issues, research studies, and other issues that may arise from program development, legislative actions, or stakeholder input. He supports high-stakes, customized assessments, and he guides continuous enhancement processes in psychometrics, research methodology, and applied statistics in assessment and automated scoring.
Previously, as a Principal Research Statistician at ACT, Inc., Dr. Schulz developed techniques based on Item Response Theory (IRT) and domain scores for assigning students to achievement levels and for quantifying the consistency and accuracy of scores. Dr. Schulz also directed contracts with the U.S. Department of Education for setting achievement levels on the National Assessment of Educational Progress (NAEP), where he led the development of the Map-mark standard setting method and its adoption for setting NAEP achievement levels. As Director of Testing at the National Council of State Boards of Nursing, Dr. Schulz supervised research and development for transitioning the nursing licensure examination to a computer-adaptive format.
Dr. Schulz has published widely and serves as a consultant to state boards of education, school districts, and licensure and certification boards on topics of equating, vertical scaling, job analysis, and computerized testing.
Dr. Schulz has a Ph.D. in Special Field of Measurement, Evaluation and Statistical Analysis (MESA) from the University of Chicago.
Dr. Nicewander has more than 30 years of experience in assessment and measurement and is a practicing expert in educational and psychological measurement. He is best known for using Item Response Theory (IRT) to solve applied testing problems and has worked in the academic, commercial, and government sectors. Dr. Nicewander has served as a Professor and Chairman of the Psychology Department at the University of Oklahoma; Director of Statistical Research for ACT, Inc.; and Head of the Department of Defense Personnel Testing Division. For the Department of Defense he oversaw the conversion of the Armed Forces Vocational Aptitude Test from paper and pencil to an adaptive, computer-administered test. While at ACT, Dr. Nicewander directed validity research on the ACT Assessment and developed IRT measurement scales for ACT tests.
Dr. Nicewander provides expertise on large-scale testing issues, conducts research and technical studies for the company’s contracts and product lines, and implements psychometric aspects of statewide assessment programs. He has written dozens of journal articles dealing with both theoretical and applied measurement. His most recently published articles deal with accounting for measurement error in selection tests, analysis of data from extreme groups, and IRT test equating using parameterized characteristic curves.
Dr. Nicewander earned a Ph. D. in Mathematical Psychology from Purdue University.
Dr. Lottridge is a highly regarded professional in the field of psychometrics, with numerous articles and technical reports published. In 2011 she became the Technical Director, Machine Scoring and is responsible for directing the development of new scoring modules and adjustments to the current engine, while ensuring that proper procedures are followed with respect to engine functioning, versioning, and quality assurance. Dr. Lottridge conceptualizes and leads research on the performance of the engine, publishes white papers on her work and presents her findings at professional conferences. In addition, she manages operational scoring, monitoring and reporting activities for scoring programs, while acting as the main contact for technical questions from current and prospective clients.
Previously, Dr. Lottridge held the position of Pacific Metrics’ Senior Psychometrician, and her responsibilities included conducting psychometric and statistical analyses, and the development and refinement of the automated scoring engine. Her psychometric work has involved a variety of analyses, including the development of IRT-based vertical scales and the comparability of paper and online tests for state-level programs. She has analyzed comparability both from an empirical and methodological perspective, including the use of innovative methods such as propensity score matching to obtain matched samples.
Prior to joining Pacific Metrics in 2006, Dr. Lottridge was a Graduate Assistant and Intern at the Center for Assessment and Research Studies at James Madison University. In this position she supported departments that developed and implemented assessments programs and assisted in the management of the test administration, data analysis, and reporting of the general education testing programs. She has also previously held the position of Associate Researcher at the Learning Through Evaluation, Adaptation and Dissemination Center where she developed evaluation plans and collected and analyzed data.
Dr. Lottridge holds a Ph.D. in Assessment and Measurement from James Madison University. In addition she has a M.S. in Computer Science, a M.A. in Mathematics from University of Wisconsin, Madison, and a B.A. in Mathematics from the University of St. Thomas, graduating Summa Cum Laude. In 2008, 2009 and 2010 she was selected to present at the Council of Chief State School Officers National Conference on Student Assessment.
