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Table 4 Simulation results when Y has an asymmetric distribution

From: Standardizing effect size from linear regression models with log-transformed variables for meta-analysis

 

Model A

\( \widehat{Y}=\widehat{\alpha}+\widehat{\beta}\cdotp X \)

Model B

\( \widehat{Y}=\widehat{\alpha}+\widehat{\beta}\cdotp { \log}_b(X) \)

Model C

\( \widehat{{ \log}_a(Y)}=\widehat{\alpha}+\widehat{\beta}\cdotp X \)

Model D

\( \widehat{{ \log}_a(Y)}=\widehat{\alpha}+\widehat{\beta}\cdotp { \log}_b(X) \)

Beta-hat coefficient and standard error from regression model

\( \widehat{\beta} \) = 0.625

se(\( \widehat{\beta} \)) = 0.254

\( \widehat{\beta} \) = 5.834

se(\( \widehat{\beta} \)) = 2.441

\( \widehat{\beta} \) = 0.011

se(\( \widehat{\beta} \)) = 0.005

\( \widehat{\beta} \) = 0.103

se(\( \widehat{\beta} \)) = 0.044

Absolute change in Y for an absolute change of c units in X

Effect size

0.625

0.557

0.551

0.493

95% CI

(0.128–1.122)

(0.101–1.013)

(0.100–1.006)

(0.080–0.909)

Absolute change in Y for a relative change of k times in X

Effect size

0.625

0.557

0.551

0.493

95% CI

(0.128–1.122)

(0.101–1.013)

(0.100–1.006)

(0.080–0.909)

Relative change in Y for an absolute change of c units in X

Effect size

1.0125

1.0111

1.0110

1.0099

95% CI

(1.0026–1.0224)

(1.0020–1.0203)

(1.0020–1.0201)

(1.0016–1.0182)

Relative change in Y for a relative change of k times in X

Effect size

1.0125

1.0111

1.0110

1.0099

95% CI

(1.0026–1.0224)

(1.0020–1.0203)

(1.0020–1.0201)

(1.0016–1.0182)

  1. Note: c = 1 and k = 1.1