[Aavso-photometry] average vs. median

[Tomas L. Gomez]

If I have N measurements, each one with error sigma,
and I take the average, then the error will be reduced
to sigma/sqrt(N).

If, instead of taking the average, I take the median,
how is the error reduced?.

Knowing this could be very useful to decide whether
to use the median of the average when stacking images,
for instance.

Thank you in advance for any help anyone can give.

-Tomas L. Gomez (GOT)