﻿ Table 11 shows how many responses were used to calculate bias estimates

# Table 11 Responses used to calculate bias estimates

Table 11 summarizes the response modeling in the bias analysis

Bias/Interaction: 1. Student, 2. Format

+--------------------------------------------------+

| Cat  Score  Exp.  Resd StRes|                    |

|-----------------------------+--------------------|

| 9.60  9.60  9.60   .01  .01 | Mean (Cnt: 296)    |

| 1.34  1.34  1.30   .31  .53 | S.D. (Population)  |

| 1.34  1.34  1.30   .31  .53 | S.D. (Sample)      |

+--------------------------------------------------+

Count of measurable responses = 296.00

Raw-score variance of observations      = 1.80 100.00%

Variance explained by Rasch measures    = 1.53  85.00%

Variance of residuals                   = 0.27  15.00%

Variance explained by bias/interactions = 0.18  10.00%

Variance remaining in residuals         = 0.09   5.00%

# Meaning

Cat

Observed value of the category in the data file

Score

Value of category in this analysis. This is less than Cat. if there are structural zeroes.

Exp.

Expected score based on current measures

Resd

Residual, the score difference between Score and Exp.

StRes

The residual divided by its standard error. The Rasch model is now over-parameterized, so the standardized residuals are expected to have an S.D. less than 1.0.

Mean

average of the observations

Cnt:

Count is the number of observations

S.D. (Population)

standard deviation treating this sample as the entire population

S.D. (Sample)

standard deviation treating this sample as a sample from the population. It is larger than S.D. (Population).

Count of measurable responses

the number of ratings used in estimating the bias terms. This may be only a small fraction of the entire data set.

Raw-score variance of observations

square of S.D. (Population) of Score in Table 11

Variance explained by Rasch measures

from Table 5

Variance of residuals

from Table 5

Variance explained by bias/interactions

Variance of Residuals - Variance remaining in residuals

Variance remaining in residuals

square of S.D. (Population) of Resd in Table 11

Help for Facets Rasch Measurement Software: www.winsteps.com Author: John Michael Linacre.

 Forum Rasch Measurement Forum to discuss any Rasch-related topic

Rasch Publications
Rasch Measurement Transactions (free, online) Rasch Measurement research papers (free, online) Probabilistic Models for Some Intelligence and Attainment Tests, Georg Rasch Applying the Rasch Model 3rd. Ed., Bond & Fox Best Test Design, Wright & Stone
Rating Scale Analysis, Wright & Masters Introduction to Rasch Measurement, E. Smith & R. Smith Introduction to Many-Facet Rasch Measurement, Thomas Eckes Invariant Measurement with Raters and Rating Scales: Rasch Models for Rater-Mediated Assessments, George Engelhard, Jr. & Stefanie Wind Statistical Analyses for Language Testers, Rita Green
Rasch Models: Foundations, Recent Developments, and Applications, Fischer & Molenaar Journal of Applied Measurement Rasch models for measurement, David Andrich Constructing Measures, Mark Wilson Rasch Analysis in the Human Sciences, Boone, Stave, Yale
in Spanish: Análisis de Rasch para todos, Agustín Tristán Mediciones, Posicionamientos y Diagnósticos Competitivos, Juan Ramón Oreja Rodríguez
Winsteps Tutorials Facets Tutorials Rasch Discussion Groups

Coming Rasch-related Events
Jan. 5 - Feb. 2, 2018, Fri.-Fri. On-line workshop: Practical Rasch Measurement - Core Topics (E. Smith, Winsteps), www.statistics.com
Jan. 10-16, 2018, Wed.-Tues. In-person workshop: Advanced Course in Rasch Measurement Theory and the application of RUMM2030, Perth, Australia (D. Andrich), Announcement
Jan. 17-19, 2018, Wed.-Fri. Rasch Conference: Seventh International Conference on Probabilistic Models for Measurement, Matilda Bay Club, Perth, Australia, Website
Jan. 22-24, 2018, Mon-Wed. In-person workshop: Rasch Measurement for Everybody en español (A. Tristan, Winsteps), San Luis Potosi, Mexico. www.ieia.com.mx
April 10-12, 2018, Tues.-Thurs. Rasch Conference: IOMW, New York, NY, www.iomw.org
April 13-17, 2018, Fri.-Tues. AERA, New York, NY, www.aera.net
May 22 - 24, 2018, Tues.-Thur. EALTA 2018 pre-conference workshop (Introduction to Rasch measurement using WINSTEPS and FACETS, Thomas Eckes & Frank Weiss-Motz), https://ealta2018.testdaf.de
May 25 - June 22, 2018, Fri.-Fri. On-line workshop: Practical Rasch Measurement - Core Topics (E. Smith, Winsteps), www.statistics.com
June 27 - 29, 2018, Wed.-Fri. Measurement at the Crossroads: History, philosophy and sociology of measurement, Paris, France., https://measurement2018.sciencesconf.org
June 29 - July 27, 2018, Fri.-Fri. On-line workshop: Practical Rasch Measurement - Further Topics (E. Smith, Winsteps), www.statistics.com
July 25 - July 27, 2018, Wed.-Fri. Pacific-Rim Objective Measurement Symposium (PROMS), (Preconference workshops July 23-24, 2018) Fudan University, Shanghai, China "Applying Rasch Measurement in Language Assessment and across the Human Sciences" www.promsociety.org
Aug. 10 - Sept. 7, 2018, Fri.-Fri. On-line workshop: Many-Facet Rasch Measurement (E. Smith, Facets), www.statistics.com
Sept. 3 - 6, 2018, Mon.-Thurs. IMEKO World Congress, Belfast, Northern Ireland www.imeko2018.org
Oct. 12 - Nov. 9, 2018, Fri.-Fri. On-line workshop: Practical Rasch Measurement - Core Topics (E. Smith, Winsteps), www.statistics.com

Our current URL is www.winsteps.com