Rasch Consultants

I have over 25 years experience as a consultant in Rasch measurement. I specialize in integrating qualitative and quantitative data and methods. Meaningfulness is of paramount importance, from my point of view. I have experience and training in Conquest, Facets, RUMM, and Winsteps. Having studied with Ben Wright at the University of Chicago, my primary skills are with Winsteps. My special interests include reliability, validity, predictive construct theory, DIF/DPF/DGF, rating scale optimization, and the use of Principal Components Analysis alongside infit, outfit, and between-groups fit analysis.

Examples of my published work can be found in both the Objective Measurement and Advances in Rasch Measurement book series, the Journal of Applied Measurement, the Journal of Outcome Measurement, Quality of Life Research, Human Studies, Theory & Psychology, the International Journal of Multiple Research Approaches, International Journal of Educational Research, and the International Journal of Transpersonal Studies. I have been a regular contributor to Rasch Measurement Transactions and the International Objective Measurement Workshops since the 1980s.

Over the last several years, consulting clients have included more than 20 state departments of education, the National Center for Special Education Accountability Monitoring (NCSEAM), the LSU School of Nursing, MetaMetrics Inc, the Social Security Administration, NSF and IES projects administered through the University of California at Berkeley's BEAR Center, as well as smaller projects conducted by a number of individual researchers and small foundations, from the Wellesley College Center for Women to NT Hope LLC. I prefer being included in the initial conceptualization and design of a study so as to ensure the fullest possible realization of the intended measurement goal. In my experience, however, significant learning can take place no matter where in the research cycle hard thinking about measurement begins.

Much more at livingcapitalmetrics.com

Graduate of MESA, University of Chicago, 1996
Psychometrician with Educational Data Systems, Morgan Hill, CA
Owner, Pythias Consulting, LLC, San Jose, CA
email: pythiasconsulting ~at~ gmail.com

I apply psychometric models to audio listening tests (Moulton Laboratories and Lucent Technologies), program evaluation (Reading First), large-scale assessment (CHSPE), data mining (profiling travelers), and district assessments (equating). My specialty is Rasch models -- including Many-Facet Rasch Models -- and multidimensional models developed under the name "NOUS" in accordance with Rasch requirements for "objectivity." My company, Pythias Consulting, markets NOUS software for specialty applications.

One such application is called EdScale, developed for Educational Data Systems. It converts test-data from district assessments administered through the school-year into California Standards Test (CST) scale scores. EdScale measures student growth within and across years and helps district administrators predict whether schools are on track to meet NCLB requirements.

I have been one of the primary architects of the California Reading First evaluation for the past 7 years, using a 3-Facet Rasch Model to measure implementation at each of over 850 schools and relating these measures to achievement gain. We have been able to demonstrate a strong Reading First effect in California (in contrast to a widely cited national study).

My work can be accessed at www.eddata.com

Consultant in Rasch, logistic models and classical models for educational evaluation and biostatistics. I give technical support from the design of a test to item analysis. I produce the family of KALT programs (including item banking, classical item analysis, on-line testing including Rasch model and criterion-referenced test and item analysis) and offer technical support and training (test design, Rasch analysis, item design and analysis). An interesting service that I am offering since 2000 is the "Analysis of quality of a test" according to international standards (among the areas that we evaluate are: validity, objectivity, reliability, logistics and application, fair test practices, research, etc.) , in this case the institution provides information and evidences of a set of elements of the test and we provide a technical report indicating the areas that are correct and the areas needing an improvement according to the standards. I can offer my services in English, Spanish and French.
Agustín Tristán
Análisis de Rasch para todos, Agustín Tristán