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Hypothesis test for a 2-group Spearman correlation difference

Source: R/statpsych2.R
test.spear2.Rd

Computes a z test for a difference of population Spearman correlations in a 2-group design. The test statistic uses a Bonett-Wright standard error for each Spearman correlation. The hypothesis testing results should be accompanied with a confidence interval for a difference in population Spearman correlation values (see ci.spear2).

Usage

test.spear2(cor1, cor2, n1, n2)

Arguments

cor1

estimated Spearman correlation for group 1

cor2

estimated Spearman correlation for group 2

n1

sample size for group 1

n2

sample size for group 2

Value

Returns a 1-row matrix. The columns are:

  • Estimate - estimate of correlation difference

  • z - z test statistic

  • p - two-sided p-value

References

Bonett DG, Wright TA (2000). “Sample size requirements for estimating Pearson, Kendall and Spearman correlations.” Psychometrika, 65(1), 23–28. ISSN 0033-3123, doi:10.1007/BF02294183 .

Examples

test.spear2(.684, .437, 100, 125)
#>  Estimate        z          p
#>     0.247 2.498645 0.01246691

# Should return:
# Estimate        z          p
#    0.247 2.498645 0.01246691