Question 1995
forgive my lack of legal jargon :-)

Group1: number of recids/17 = 0.12 --> no recids = 2  in this group
Group2: number of recids/19 = 0.37 --> no recids = 7  in this group
Group3: number of recids/22 = 0.55 --> no recids = 12 in this group

so combined, total number of recids = 21
and total number of offenders = 58

so mean value = (21/58)*100 = 36%

NEVER EVER EVER EVER just add the 3 means and divide by 3...the 3 sets have different sizes and so their is a weighting.

Jon.