I've just had a quick look at L21+ compared to M222+ in terms of proportion on modal over 67 markers. L21+ is about 80% on modal compared to about 90% for M222+, so yes, M222+ is pretty immature compared to L21+. When you say "If M222 is as young as we think.." do you mean 'we' in the broad sense, or do you mean 'we' as in L21 researchers? I'd be very keen to discuss various different approaches to the dating problem with someone who can cast a jaundiced eye on various mathematical approaches. I also think it could be quite productive to have some cross-pollination of ideas between those who are interested in M222 and those who are interested in L21. Thanks, I'll contact Mike about M222 lookalikes. Sandy -----Original Message----- From: dna-r1b1c7-bounces@rootsweb.com [mailto:dna-r1b1c7-bounces@rootsweb.com] On Behalf Of Stephen Forrest Sent: 22 July 2011 04:41 To: dna-r1b1c7@rootsweb.com Subject: Re: [R-M222] Calculation of a correlation coeficient I have no information about that, but I'm just a participant. You could try asking one Mike (one of the RL21Project admins, email address mwwdna@gmail.com).