summary table for probability that random draw x1 is larger than x2
Parameters:
alpha (float) – Significance level for confidence intervals. Coverage is 1 - alpha
xname (None or list of str) – If None, then each row has a name column with generic names.
If xname is a list of strings, then it will be included as part
of those names.
Returns:
SimpleTable instance with methods to convert to different output