Cited by 487Statistical Methods and Bayesian InferenceSurvey Sampling and Estimation TechniquesOptimal Experimental Design Methods

Standard Errors and Sample Sizes for Two-Level Research

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Snijders, Tom A. B., Bosker, Roel J.·1993·Journal of Educational Statistics

Abstract

The hierarchical linear model approach to a two-level design is considered, some variables at the lower level having fixed and others having random regression coefficients. An approximation is derived to the covariance matrix of the estimators of the fixed regression coefficients (for variables at the lower and the higher level) under the assumption that the sample sizes at either level are large enough. This covariance matrix is expressed as a function of parameters occurring in the model. If a research planner can make a reasonable guess as to these parameters, this approximation can be used as a guide to the choice of sample sizes at either level.

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Registry

Crossref · 10.3102/10769986018003237

Cites

17 of 17 references verified0 citation errors · 0 not checkable

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  • Post hoc power analyses confirmed sufficient power (>.80) to detect a mediated pathway comprising paths of medium effect sizes and to detect a medium effect size for treatment condition as a moderator of the mediated pathways.

    “Post hoc power analyses using the multilevel power analysis program PinT (Snijders & Bosker, 1993) confirmed that we had sufficient power (>.80) to detect a mediated pathway comprising paths that were of medium effect sizes and to detect a medium effect size for treatment condition as a moderator of the mediated pathways.”

    From Respiratory and cognitive mediators of treatment change in panic disorder: Evidence for intervention specificity. (2010) · cites this paper as Snijders & Bosker, 1993

    The Determination of Optimal Sample Sizes section describes formulas for power analysis in two-level designs, supporting the citation’s methodological context. Our copy does not identify or describe the PinT program (searched: PinT and software). The >.80 power result concerns the citing authors’ own post hoc analyses, not a result attributed to Snijders and Bosker. (LLM, conf=0.76)

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  • Brief CBT is no more effective than usual care when it comes to preventing repetition of self-harm.

    “Tyrer et al reported that brief CBT is no more effective than usual care when it comes to preventing repetition of self-harm, 15”

    From Cognitive-behavioural intervention for self-harm: Randomised controlled trial (2008) · cites this paper as [15]

    The paper’s discussion of standard errors and sample sizes for two-level research (Abstract; Determination of Optimal Sample Sizes) does not address CBT, usual care, or repetition of self-harm. Searches for those terms and for Tyrer found no relevant passage in our copy. (LLM, conf=0.79)

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  • This study's finding that time-limited CBT decreases self-harm contrasts with the results reported by Tyrer et al.

    “Furthermore, this study's findings that time-limited CBT decreases self-harm contrasts with the results reported by Tyrer et al . 15”

    From Cognitive-behavioural intervention for self-harm: Randomised controlled trial (2008) · cites this paper as [15]

    The paper’s Abstract discusses standard errors and sample sizes for two-level models, not CBT or self-harm. Searches for Tyrer, time-limited CBT, and self-harm found no passage addressing the cited comparison. (LLM, conf=0.78)

    Experimental — accuracy not yet measured

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Cites

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Research works printed but not linked: 4

  1. Aitkin, M., & Longford, N. T. (1986). Statistical modeling issues in school effective- ness studies (with discussion). Journal of the Royal Statistical Society, Series A , 144, 419-461.
  2. Cochran, W. G. (1977). Sampling techniques (3rd ed.). New York: Wiley.
  3. Efron, B., & Morris, C. (1975). Data analysis using Stein's estimator and its gener- alizations. Journal of the American Statistical Association, 74, 311-319.
  4. Kreft, G. G. (1987). Models and methods for the measurement of school effects. Unpublished doctoral dissertation, University of Amsterdam, The Netherlands.

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Authors
Snijders, T. A. B., & Bosker, R. J.
Affiliations
  • University of Groningen (NL)
  • University of Twente (NL)
Venue
Journal of Educational Statistics
Published
1993-09
Volume
18
Issue
3
Pages
237-259
ISSN
0362-9791 (ISSN-L)
OpenAlex
W2097507923
Cited by
487
References
17
Citations by year
2026: 11 · 2025: 13 · 2024: 14 · 2023: 14 · 2022: 14 · 2021: 27 · 2020: 26 · 2019: 34 · 2018: 20 · 2017: 28 · 2016: 22 · 2015: 25 · 2014: 24 · 2013: 35 · 2012: 21
FWCI
1.01
Type
journal article
Language
en
Open access
Locations
  • Journal of Educational Statistics (publishedVersion)
  • University of Twente Research Information (submittedVersion, other-oa)
  • RePEc: Research Papers in Economics (submittedVersion)
  • University of Groningen research database (University of Groningen / Centre for Information Technology) (submittedVersion)
Topics
  • Physical Sciences › Mathematics › Statistics and Probability › Statistical Methods and Bayesian Inference
  • Physical Sciences › Mathematics › Statistics and Probability › Survey Sampling and Estimation Techniques
  • Social Sciences › Decision Sciences › Management Science and Operations Research › Optimal Experimental Design Methods
Keywords
two-level designs, multilevel analysis, standard errors, sample size determination, covariance matrix approximation, multilevel data

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