Exercise

Standardized effect inference

In comparing my reaction times with those of my son Steven, we are interested in the regression model

$$ Time = \beta_0 + \beta_1 * Person $$

The parameter beta1 measures the change (from me to Steven) in mean reaction time and the parameter

delta = beta1 / S

represents the standardized change (in standard deviation units).

Instructions

100 XP
  • Perform a regression fit of Time using Person as a covariate.
  • Simulate 1000 draws from the joint posterior distribution using the sim() function.
  • Extract the simulated values of (beta0, beta1) and S (functions coef() and sigma.hat()).
  • Compute the simulated values of the standardized change delta.
  • Find a 90% interval estimate for delta.