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DMAR (version 1.0.0)

convert_R2: Convert Between F, \(R^2\), and Their Noncentral Parameters

Description

Given values of test statistics (and the appropriate additional information) the value of the noncentral values can be obtained. Likewise, given noncentral values (and the appropriate additional information) the value of the test statistic can be obtained.

Usage

convert_R2_f(R2 = NULL, df_1 = NULL, df_2 = NULL, p = NULL, N = NULL)

convert_f_R2(F_value = NULL, df_1 = NULL, df_2 = NULL)

convert_lambda_R2(lambda = NULL, N = NULL)

convert_R2_lambda(R2 = NULL, N = NULL)

Value

Each of the four functions returns a 1-row data.frame

with columns term and value. The term entry identifies the conversion performed ("r2_f", "f_r2", "lambda_r2", or

"r2_lambda") and value is the converted scalar. The conversions are exact inverses of one another (with the appropriate degrees-of-freedom / sample size inputs supplied), which is what makes them useful inside the noncentrality-parameter confidence interval machinery of ci_R2 and

ci_nc_F.

Arguments

R2

Squared multiple correlation coefficient (population or observed)

df_1

Degrees of freedom for the numerator of the F-distribution

df_2

Degrees of freedom for the denominator of the F-distribution

p

Number of predictor variables for R2

N

Sample size

F_value

The obtained F value from a test of significance for the squared multiple correlation coefficient

lambda

The noncentral parameter from an F-distribution

Author

Ken Kelley [email protected]

Details

These functions are especially helpful in the search for confidence intervals for noncentral parameters, as they convert to and from related quantities.

References

Kelley, K. (2007). Confidence intervals for standardized effect sizes: Theory, application, and implementation. Journal of Statistical Software, 20(8), 1--24. tools:::Rd_expr_doi("10.18637/jss.v020.i08")

See Also

ss_aipe_R2, ci_R2, ci_nc_t, ci_nc_F

Other parameterization conversions: convert_F_chisq(), convert_Z_r(), convert_cor_cov(), convert_d_or(), convert_d_r(), convert_r_Z(), convert_t_smd, convert_z_normal()

Examples

Run this code
convert_R2_lambda(R2 = .5, N = 100)

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