Generic sensitizing for Rosenbaum & Rubin sensitivity analysis
sensitize(obj, q, dp, d0, d1, ...)
data to sensitize
p(u = 1 | x)
change in log-odds of treat = 1 if u = 1
change in log-odds of response = 1 if treat = 0 and u = 1
change in log-odds of response = 1 if treat = 1 and u = 1
additional arguments required to sensitize object
a sensitized object, identical to, or inheriting the class of
original obj