  Considering the complex reflection amplitude R=|R|exp(i{\theta}) of a light
wave, real delay time {\tau}_r (i.e., sojourn or Wigner delay time), which is
the energy derivative of the real phase ({\tau}_r =d{\theta}/cdk), and complex
delay time {\tau}_i , which is the energy derivative of the reflection
coefficient ({\tau}_i=d{\theta}_i/cdk, |R|=r^1/2=exp(-{\theta}_i)), have the
same statistical form and a mirror image with a shift in time in weak disorder
and short length regime. Real delay time statistics obtained from the
reflection coefficient can be attributed to the strong correlation between the
reflection coefficient and its phase in this regime.
