Welcome to VPG Online Store

Vector Psychometric Group (VPG) is proud to offer cutting-edge software for web-based data collection and item response data analysis.

  • flexMIRT®, VPG’s flagship IRT software, has some of the richest psychometric and statistical features defining the state of the art. With the ability to be installed and called remotely, flexMIRT® is ideal for the individual analyses of an applied researcher or the large-scale analyses and scoring needed for operational use.
  • IRTPRO™, with its intuitive graphical user interface, built-in data management capacity, high quality graphics, and a professional HTML-based output delivery system, have become widely adopted by educators, researchers, and assessment professionals.
  • Adaptest®, our web-based computerized adaptive testing (CAT) engine, has been updated to a “plug-in,” allowing any existing electronic data collection system (EDC) to administer adaptive tests and provide real-time scoring with minimal modifications.

With your renewable VPG subscription, you are entitled to many more benefits in comparison to previous licensing models. Click here to view a side-by-side comparison chart of features.

Through the end of 2020, we are happy to offer a 5% discount to select flexMIRT® and IRTPRO™ license types. Simply use the discount code: DISCOUNT2020 at check out. 

Featured products

flexMIRT®

Regular flexMIRT license
$1,950.00

IRTPRO™

Purchasing a license for IRTPRO™ is easy. You can purchase and download a regular non-operational copy of IRTPRO™ from within My Account. Annual licenses are available for single users (3 installs) for $1,950 per year. Additional users can be added to your annual license for only $325 per user (3 installs). If you would like to add additional installs to a single license or link multiple user accounts under one license, please contact us for more information.
$1,950.00

flexMIRT® - Academic

flexMIRT® for Student and Faculty
$325.00

IRTPRO™ - Academic

IRTPRO™ for Student and Faculty
$325.00

Products:

flexMIRT®

flexMIRT® is software specifically designed for the analysis of item response data, such as what can be obtained from a quality of life measure, attitude survey, or academic test. It is able to accommodate a wide variety of IRT models to factor structures that are both unidimensional and multidimensional (e.g., the items measure more than one concept). flexMIRT® provides a wide variety of item and model fit statistics and indices for evaluating results and produces several different types of IRT-based scores, depending on user request. While flexMIRT® is primarily a confirmatory modeling program, it has capabilities for performing EFA with analytic rotations as well.



IRTPRO™

IRTPRO™ is an advanced application for item calibration and test scoring using item response theory (IRT).  It comes with an intuitive graphical user interface and offers built-in production quality IRT graphics.  Suitable for educators, students, researchers, and assessment organizations, IRTPRO™ has become increasingly popular in the educational, psychological, social, and health sciences.  IRTPRO™ handles any combination of unidimensional or multidimensional versions of popular IRT models, in multiple groups.  The users may choose from a number of sophisticated estimation algorithms for item and person parameters.  User-defined parameter restrictions and the availability of many test statistics facilitate statistical inference for IRT modeling.