Quality of Measurement and Sample Size

  • William J. Boone
  • John R. Staver
  • Melissa S. Yale


In earlier chapters, readers learn of the importance of where items are located on a trait and where persons fall on a trait when item measures are considered. Of importance to the measurement of persons and items is the sample size of items and persons. This chapter introduces the issue of sample size and the myriad of issues related to sample size when they conduct measurement. Researchers can obtain a great deal of information much from research with a small sample of respondents (e.g., less than 30) and a small number of items (e.g., 10). What is possible from a sample in part depends upon what one wants to learn, where items are located along a trait, and where persons are located on a trait. The chapter finishes up with a student dialog, Keywords and Phrases, Quick Tips, Data Files, References, and Additional Readings. As in almost all chapters, sample analyses are used to reinforce the chapter topic.


Item Difficulty Person Measure Person Sample Item Reliability Item Error 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.


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Additional Readings

  1. Smith, E. V., Jr., & Smith, R. M. (Eds.). (2004). Introduction to Rasch measurement: Theory, models, and applications. Maple Grove, MN: JAM Press.Google Scholar
  2. Smith, A., Rush, R., Fallowfield, L., Velikova, G., & Sharpe, M. (2008). Rasch fit statistics and sample size considerations for polytomous data. BMC Medical Research Methodology, 8, 33. doi: 10.1186/1471-2288-8-33.CrossRefGoogle Scholar
  3. Stone, M., & Yumoto, F. (2004). The effect of sample size for estimating Rasch/IRT parameters with dichotomous items. Journal of Applied Measurement, 5(1), 48–61.Google Scholar

Copyright information

© Springer Netherlands 2014

Authors and Affiliations

  • William J. Boone
    • 1
  • John R. Staver
    • 2
  • Melissa S. Yale
    • 3
  1. 1.Miami UniversityOxfordUSA
  2. 2.Purdue UniversityWest LafayetteUSA
  3. 3.IrvingUSA

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