Statistical Consultation Line: (865) 742-7731
Accredited Professional Statistician For Hire
  • Contact Form

Sphericity

Sphericity tests for artificial inflation or deflation of covariance matrices

The statistical assumption of sphericity comes into play when conducting repeated-measures ANOVA. In essence, sphericity accounts for the random variation and error associated with measurement in inferential statistics. Multiple observations of an outcome can artifically inflate or deflate the underlying covariance matrices associated with the algebra used when calculating the degrees of freedom and F-value for repeated-measures ANOVA. The assumption of sphericity is often not met when conducting repeated-measures ANOVA analyses, strictly due to the aforementioned variation and error that exists when collecting more than two observations of a continuous outcome.  

The Greenhouse-Geisser correction is used to correct for sphericity. Click on the button below to learn more about interpreting the Greenhouse-Geisser correction and sphericity in SPSS.

Sphericity and applied statistics

Repeated-Measures ANOVA
Back to Statistical Assumptions
Research Engineer Home Page

Statistician For Hire

$100.00
Buy Now

DO YOU NEED TO HIRE A STATISTICIAN?

Eric Heidel, Ph.D. will provide statistical consulting for your research study at $100/hour. Secure checkout is available with PayPal, Stripe, Venmo, and Zelle.

  • Statistical Analysis
  • Sample Size Calculations
  • Diagnostic Testing and Epidemiological Calculations
  • Psychometrics

Contact Dr. Eric Heidel
consultation@scalelive.com
(865) 742-7731

Copyright © 2022 Scalë. All Rights Reserved. Patent Pending.