for a continous target variable A_g, a subgroup h is considered "unusual" if
3. the mean value of T in c(h) is significantly different from its mean value in  r_o
 

Let m := (St in c(h) t[ Ag ]) / |c(h)|, m0 := (St in  ro  t [Ag ]) / | ro |,  g = |c(h)| / | ro |    d(h):= g^a * (m- m0)                                                         (0 if g < s0)

 
Alternative (only for multi-group comparisons!): cumulated shares.

4. the cumulated share of captured by h in T is significantly different from the share of reference group h₀ in T