For judged ratings and complex ordinal data structures...

Facets

Many-Facet Rasch Analysis

Current versions: Facets 3.64.0 enhancements, June 2008; Facform 1.64. Purchase from SWREG

Windows-native, but please check compatibility with your version of Windows, by installing the free student/evaluation version. (Can run under Virtual-PC on the Mac.)

Watch Facets in action: Run "FacetsIntroduction.exe" (2MB software)

Free, Windows-native, evaluation/student version of FACETS, called MINIFAC. Contains all features except limited to 2,000 data points (responses). Please copy, distribute and use.

Winsteps vs. Facets comparison

Facets introductory workshops: see "Coming Events" below

Customer support policy and user comments.

Facets users and site license holders

List of citations to Facets in scholarly Papers

Facets installation problems?

Facets Probability Graph
Click here for bigger picture.




Facform, free data-formatter for Facets

Our recommendation: use EXCEL etc. instead

  1. Freeware Facform data formatter Download FacformInstall.exe

Facets & Facform User Manuals On-Line

Go to Facets Online Help

Go to Facform Online Help for Facets data formatter


For free Facets and Facform User Mnauals in PDF format, mostly same as "Help" files.

  1. Free Facets User Manual PDF Download facets.pdf
  2. Free Facform User Manual PDF Download facform.pdf


Facets


Staff of Suzann Campbell's baby-measuring project.
See RMT 10:2.

Cover of McNamara: Measuring Second Language Performance
Useful for all Facets users: "Measuring Second Language Performance" by T. F. McNamara, Addison-Wesley Longman, 1996. Available from Barnes & Noble. or Amazon.com
The book "Many-Facet Rasch Measurement" by John M. Linacre, Chicago: MESA Press, 1992, is available from https://mmm1406.sanjose14-verio.com/rascho/books.htm

Go to Example of Facets Output

Facets Features
Facets Features
 

Facets is designed to handle really tough applications of unidimensional Rasch measurement. It constructs measures from complex data involving heterogeneous combinations of examinees, items, tasks, judges along with further measurement and structural facets. It is designed to handle flexibly combinations of items of different formats in one analysis. Item types include dichotomies, rating scales with up to 255 categories, Poisson counts and Bernoulli trials. Multiple different measurement models can be included in the same analysis, including paired-comparisons, rank- order, rating scales, partial credit and dichotomizations involving from 1 to 255 facets. Measures can also be fixed (anchored) individually or by group mean, facilitating equating and linking across test sessions. Quality-control fit evaluation of all measures is provided. Unexpected data points are identified. Bias, differential item functioning and interactions can be measured. Weighting schemes can be implemented. Up to 1 million examinees etc. can be included in one analysis. Typical applications have over 90% missing data. Since organizing the data for input to Facets and then interpreting its output can be challenging, it is recommended that simpler approaches be tried first. Facets has been used successfully to construct measures for medical staff performance, patient performance, public speaking, sports performance by individuals and teams, and consumer preferences. Training seminars are held regularly. Student/evaluation versions of Facets can be downloaded free from www.winsteps.com.

Recent enhancements, changes and bug fixes to Facets.


Description of FACETS program

This program extends the objective measurement principles of Georg Rasch beyond conventional tests and attitude surveys into more complex areas such as judged performances, and sub-tests of items replicated across tasks. Facets has already been applied in many areas including Drama Competition, Laboratory Technician Certification, Handicapped Patient Assessment, Stain Resistance of Paints, Public Speaking Competence, Graduate-School Candidate Selection, Teacher Assessment and Essay Grading.

Judged tests can be analyzed: Facets can analyze the ratings awarded by judges to examinees who are being tested on their performance on a number of different skill items for each of several tasks. The choice of judging design is yours: from complete designs in which every judge rates every examinee, to minimal designs in which any judge only rates a few of the examinees on a few of the items. The only constraint is that there be enough overlap or rotation in the judging design to enable each parameter to be uniquely positioned within one overall frame of reference.

Heterogeneous tests can be analyzed together: Not only can Facets perform analyses as diverse as dichotomous responses and judge- awarded ratings, but Facets can process them together simultaneously in one analysis to estimate one ability measure for each examinee.

Mathematical flexibility: The analyst specifies to Facets the number of facets in the data, and, for each facet, its name and the names of all the parameters included in the facet. The analyst also specifies the form of the measurement model which represents the way in which the facets interacted to produce the observations, and which observations apply to a given model, so that multiple measurement models can be used simultaneously in one analysis. For a complex judged test, the measurement model could be equivalent to:

log(Pnmijk / Pnmijk-1) = Bn - Am - Di - Cj - Fk

where Bn = ability of examinee n, Am = difficulty of task m, Di = difficulty of skill item i, Cj = severity of judge J, Fk = difficulty of category k relative to category k-1, Pnmijk = probability of rating of k under these circumstances, Pnmijk-1 = probability of rating of k-1

Rasch analysis programs available from:

Winsteps, PO Box 811322, Chicago IL 60681-1322, USA
Tel. & FAX (312) 264-2352
Winsteps® is a registered trademark


FACETS operational flowchart


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For more information, contact
Rasch measurement software and publications by e-mail using the comment form above.
Our current URL is www.winsteps.com

Winsteps, PO Box 811322, Chicago IL 60681-1322, USA
Tel. & FAX (312) 264-2352

The URL of this page is www.winsteps.com/facets.htm

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