Understanding Correlation: Factors That Affect the Size of r

2006/04/01 by Laura D. Goodwin, Nancy L. Leech · 480 citations
Computer Science · Decision Sciences · Mathematics · Psychology · #Advanced Statistical Methods and Models #Advanced Statistical Modeling Techniques #Affect (linguistics) #Correlation #Econometrics #Geometry #Linearity #Mathematics #Optimal Experimental Design Methods #Outlier #Pearson product-moment correlation coefficient #Physics #Psychology #Sample size determination #Statistics

paper · doi:10.3200/jexe.74.3.249-266

published in The Journal of Experimental Education 74(3), 249-266 (Taylor & Francis)

openalex publication_date 2006/04/01 · openalex created_date 2025/10/10 · openalex updated_date 2026/08/04

Abstract

. 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.

Citations

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