interaction_params {simpr.interaction} | R Documentation |
Extract simulation parameters for power analysis of regression interaction models.
Description
Extract useful simulation parameters for regression.interaction models,
computed via change in R2. This function is largely a wrapper for
power_interaction_r2()
from the InteractionPoweR
package which calculates useful quantities based
on correlations and reliabilities. This function then massages the output into
a more convenient format for simpr as well as calculating R2 and sigma.
Usage
interaction_params(
r.x1.y,
r.x2.y,
r.x1x2.y,
r.x1.x2,
rel.x1 = 1,
rel.x2 = 1,
rel.y = 1
)
Arguments
r.x1.y |
Pearson's correlation between x1 and y. Must be between -1 and 1. |
r.x2.y |
Pearson's correlation between x2 and y. Must be between -1 and 1. Assumed to be the 'moderator' in some functions. |
r.x1x2.y |
Pearson's correlation between the interaction term x1x2 (x1 * x2) and y. Must be between -1 and 1. |
r.x1.x2 |
Pearson's correlation between x1 and x2. Must be between -1 and 1. Has no default value. |
rel.x1 |
Reliability of x1 (e.g. test-retest reliability, ICC, Cronbach's alpha). Default is 1 (perfect reliability). Must be greater than 0 and less than or equal to 1. |
rel.x2 |
Reliability of x2 (e.g. test-retest reliability, ICC, Cronbach's alpha). Default is 1 (perfect reliability). Must be greater than 0 and less than or equal to 1. |
rel.y |
Reliability of y (e.g. test-retest reliability, ICC, Cronbach's alpha). Default is 1 (perfect reliability). Must be greater than 0 and less than or equal to 1. |
Value
A list with the following elements:
b1: |
Slope for simulation of x1 |
b2: |
Slope for simulation of x2 |
b3: |
Slope for simulation of x1:x2 |
obs.r.x1.x2: |
Adjusted correlation of x1 and x2 |
obs.r.x1.y: |
Adjusted correlation of x1 and y |
obs.r.x2.y: |
Adjusted correlation of x1 and y |
obs.r.x1x2.y: |
Adjusted correlation of x1:x2 and y |
r2: |
R-squared |
sigma: |
Sigma |
cov: |
Adjusted correlation matrix of x1 and x2 |
Examples
params_all = interaction_params(r.x1.y = -0.18,
r.x2.y = -0.03,
r.x1.x2 = 0.64,
r.x1x2.y = 0.1,
rel.y = 0.79,
rel.x1 = 0.89,
rel.x2 = 0.95)