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Understanding Correlation: Factors That Affect the Size of r
RSEM Faculty Publications
  • Laura D. Goodwin
  • Nancy L. Leech, School of Education and Human Development at the University of Colorado Denver
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The authors describe and illustrate 6 factors that affect the size of a Pearson correlation: (a) the amount of variability in the data, (b) differences in the shapes of the 2 distributions, (c) lack of linearity, (d) the presence of 1 or more "outliers," (e) characteristics of the sample, and (f) measurement error. Also discussed are ways to determine whether these factors are likely affecting the correlation, as well as ways to estimate the size of the influence or reduce the influence of each.
Citation Information
Laura D. Goodwin and Nancy L. Leech. "Understanding Correlation: Factors That Affect the Size of r" (2006)
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