Please correct me if I am wrong, but false positives (sadly, a very general term) are small segments that are neither identical by descent (IBD) or identical by state (IBS) and may be a result of the way the companies are processing the half-identical regions (HIR) information or they may be a mish-mash of paternal and maternal alleles. If two people you match do not match each other, then it is only that each of those you match are on a different chromosome (these are different HIRs). E -----Original Message----- From: autosomal-dna-bounces@rootsweb.com [mailto:autosomal-dna-bounces@rootsweb.com] On Behalf Of Jim Bartlett Sent: Saturday, October 19, 2013 6:17 AM To: autosomal-dna@rootsweb.com Subject: Re: [AUTOSOMAL-DNA] Family finder matches what to make of them Karen False positives from FF ICW can be determined by asking the two Matches in question if they match each other on the same segment you match them. Either one can confirm it. Also you can easily compare them at GEDmatch to see if and how much and where they share (if they'll upload to GEDmatch). Also you can confirm them, one at a time, if they match a close cousin (your close cousin can confirm the segment if you don't manage their kit). I would never think about comparing raw data. If they won't cooperate at all (as above), they surely won't give you their raw data, either. Jim - Sent from my iPhone - FaceTime! On Oct 19, 2013, at 7:52 AM, Karen Hodges <rowantreek@gmail.com> wrote: > Hi Jim > > Thanks for your comments. I think I am good with the true matches now > but the false positives can these only be determined by comparing the > raw DNA when no genealogy match is found and is there a program that can do this? > > Karen > > > On Sat, Oct 19, 2013 at 10:12 PM, Jim Bartlett <jim4bartletts@verizon.net>wrote: > >> Karen >> >> In general I agree with Tim. I would add that Triangulation has a >> very specific requirement: A=B=C=A. That is each pair (AB,AC,BC) must >> have a shared segment (usually at least 7cM, but perhaps smaller with >> some risk of a false positive); AND each of these shared segments are >> significantly overlapping - such that all three - ABC - have, say, at least the same 7cM. >> You can accept a little less overlap, by accepting a little more risk >> that it's not right. With so much randomness in atDNA, we cannot >> guarantee anything. ______________________________ For answers to Frequently Asked Questions about mailing lists, please see: http://dgmweb.net/MailingListFAQs.html ------------------------------- To unsubscribe from the list, please send an email to AUTOSOMAL-DNA-request@rootsweb.com with the word 'unsubscribe' without the quotes in the subject and the body of the message

I was responding in the context of FF ICW. I took false positives to mean cases where 2 Matches were ICW each other (seemingly positive), but turn out to be matching on a different Chr (thus not forming a Triangulated Group - i.e. false). Sorry if the context was different and I missed it. If the question is how do you detect that a reported match is really IBS. Note there are several ways to get an IBS segment, but they all have the same bottom line - an IBS segment does not come from a Common Ancestor. The way I determine an IBS segment is when that Match doesn't match others on that segment who shave already been shown to have IBD segments on both sides. In other words the IBS segment should/would match with other segments, but doesn't. I note it as a probable IBS segment, and move on to other Matches. There is so much to check and document, that I won't dwell on these stumbling blocks. Focus on more promising leads. It was my understanding that all "shared" segments (of any size) were either IBD or IBS - there is no third category?? Jim - Sent from my iPhone - FaceTime! On Oct 19, 2013, at 12:05 PM, "Emily Aulicino" <aulicino@hevanet.com>wrote: > Please correct me if I am wrong, but false positives (sadly, a very general > term) are small segments that are neither identical by descent (IBD) or > identical by state (IBS) and may be a result of the way the companies are > processing the half-identical regions (HIR) information or they may be a > mish-mash of paternal and maternal alleles. > > If two people you match do not match each other, then it is only that each > of those you match are on a different chromosome (these are different HIRs). > > E > > -----Original Message----- > From: autosomal-dna-bounces@rootsweb.com > [mailto:autosomal-dna-bounces@rootsweb.com] On Behalf Of Jim Bartlett > Sent: Saturday, October 19, 2013 6:17 AM > To: autosomal-dna@rootsweb.com > Subject: Re: [AUTOSOMAL-DNA] Family finder matches what to make of them > > Karen > > False positives from FF ICW can be determined by asking the two Matches in > question if they match each other on the same segment you match them. Either > one can confirm it. > > Also you can easily compare them at GEDmatch to see if and how much and > where they share (if they'll upload to GEDmatch). > > Also you can confirm them, one at a time, if they match a close cousin (your > close cousin can confirm the segment if you don't manage their kit). > > I would never think about comparing raw data. If they won't cooperate at all > (as above), they surely won't give you their raw data, either. > > Jim - Sent from my iPhone - FaceTime! > > On Oct 19, 2013, at 7:52 AM, Karen Hodges <rowantreek@gmail.com> wrote: > >> Hi Jim >> >> Thanks for your comments. I think I am good with the true matches now >> but the false positives can these only be determined by comparing the >> raw DNA when no genealogy match is found and is there a program that can > do this? >> >> Karen >> >> >> On Sat, Oct 19, 2013 at 10:12 PM, Jim Bartlett > <jim4bartletts@verizon.net>wrote: >> >>> Karen >>> >>> In general I agree with Tim. I would add that Triangulation has a >>> very specific requirement: A=B=C=A. That is each pair (AB,AC,BC) must >>> have a shared segment (usually at least 7cM, but perhaps smaller with >>> some risk of a false positive); AND each of these shared segments are >>> significantly overlapping - such that all three - ABC - have, say, at > least the same 7cM.

Hi Jim Yes what you responded to was what I was after. Understanding IBS and the other area that Emily brought up, better, means I won't interrupt a non genealogy match as anything more. >From what I have read 10cMs plus is IBD and under 7cMs can be IBD or IBS while 7cM-10cM is also either but more chance of being IBD. under 7cMs matches that match only me on a chromosome By that I meant the ICW match doesn't have the same match in the same location as me and my link to that match is below 7cMs increasing the possibility of being IBS. Your answer, answers my question well. Thank you Karen On Sun, Oct 20, 2013 at 10:02 AM, Jim Bartlett <jim4bartletts@verizon.net>wrote: > I was responding in the context of FF ICW. I took false positives to mean > cases where 2 Matches were ICW each other (seemingly positive), but turn > out to be matching on a different Chr (thus not forming a Triangulated > Group - i.e. false). Sorry if the context was different and I missed it. > > If the question is how do you detect that a reported match is really IBS. > Note there are several ways to get an IBS segment, but they all have the > same bottom line - an IBS segment does not come from a Common Ancestor. > > The way I determine an IBS segment is when that Match doesn't match others > on that segment who shave already been shown to have IBD segments on both > sides. In other words the IBS segment should/would match with other > segments, but doesn't. I note it as a probable IBS segment, and move on to > other Matches. There is so much to check and document, that I won't dwell > on these stumbling blocks. Focus on more promising leads. > > It was my understanding that all "shared" segments (of any size) were > either IBD or IBS - there is no third category?? > > Jim - Sent from my iPhone - FaceTime! > > On Oct 19, 2013, at 12:05 PM, "Emily Aulicino" <aulicino@hevanet.com > >wrote: > > > Please correct me if I am wrong, but false positives (sadly, a very > general > > term) are small segments that are neither identical by descent (IBD) or > > identical by state (IBS) and may be a result of the way the companies are > > processing the half-identical regions (HIR) information or they may be a > > mish-mash of paternal and maternal alleles. > > > > If two people you match do not match each other, then it is only that > each > > of those you match are on a different chromosome (these are different > HIRs). > > > > E > > > > -----Original Message----- > > From: autosomal-dna-bounces@rootsweb.com > > [mailto:autosomal-dna-bounces@rootsweb.com] On Behalf Of Jim Bartlett > > Sent: Saturday, October 19, 2013 6:17 AM > > To: autosomal-dna@rootsweb.com > > Subject: Re: [AUTOSOMAL-DNA] Family finder matches what to make of them > > > > Karen > > > > False positives from FF ICW can be determined by asking the two Matches > in > > question if they match each other on the same segment you match them. > Either > > one can confirm it. > > > > Also you can easily compare them at GEDmatch to see if and how much and > > where they share (if they'll upload to GEDmatch). > > > > Also you can confirm them, one at a time, if they match a close cousin > (your > > close cousin can confirm the segment if you don't manage their kit). > > > > I would never think about comparing raw data. If they won't cooperate at > all > > (as above), they surely won't give you their raw data, either. > > > > Jim - Sent from my iPhone - FaceTime! > > > > On Oct 19, 2013, at 7:52 AM, Karen Hodges <rowantreek@gmail.com> wrote: > > > >> Hi Jim > >> > >> Thanks for your comments. I think I am good with the true matches now > >> but the false positives can these only be determined by comparing the > >> raw DNA when no genealogy match is found and is there a program that can > > do this? > >> > >> Karen > >> > >> > >> On Sat, Oct 19, 2013 at 10:12 PM, Jim Bartlett > > <jim4bartletts@verizon.net>wrote: > >> > >>> Karen > >>> > >>> In general I agree with Tim. I would add that Triangulation has a > >>> very specific requirement: A=B=C=A. That is each pair (AB,AC,BC) must > >>> have a shared segment (usually at least 7cM, but perhaps smaller with > >>> some risk of a false positive); AND each of these shared segments are > >>> significantly overlapping - such that all three - ABC - have, say, at > > least the same 7cM. > > > > ______________________________ > For answers to Frequently Asked Questions about mailing lists, please see: > http://dgmweb.net/MailingListFAQs.html > > > ------------------------------- > To unsubscribe from the list, please send an email to > AUTOSOMAL-DNA-request@rootsweb.com with the word 'unsubscribe' without > the quotes in the subject and the body of the message >

Hi Emily I was wondering what a mish mash of paternal and maternal alleles was? . Your comment is much appreciated. What is HIR short for please? Karen On Sun, Oct 20, 2013 at 3:05 AM, Emily Aulicino <aulicino@hevanet.com>wrote: > Please correct me if I am wrong, but false positives (sadly, a very general > term) are small segments that are neither identical by descent (IBD) or > identical by state (IBS) and may be a result of the way the companies are > processing the half-identical regions (HIR) information or they may be a > mish-mash of paternal and maternal alleles. > > If two people you match do not match each other, then it is only that each > of those you match are on a different chromosome (these are different > HIRs). > > E > > -----Original Message----- > From: autosomal-dna-bounces@rootsweb.com > [mailto:autosomal-dna-bounces@rootsweb.com] On Behalf Of Jim Bartlett > Sent: Saturday, October 19, 2013 6:17 AM > To: autosomal-dna@rootsweb.com > Subject: Re: [AUTOSOMAL-DNA] Family finder matches what to make of them > > Karen > > False positives from FF ICW can be determined by asking the two Matches in > question if they match each other on the same segment you match them. > Either > one can confirm it. > > Also you can easily compare them at GEDmatch to see if and how much and > where they share (if they'll upload to GEDmatch). > > Also you can confirm them, one at a time, if they match a close cousin > (your > close cousin can confirm the segment if you don't manage their kit). > > I would never think about comparing raw data. If they won't cooperate at > all > (as above), they surely won't give you their raw data, either. > > Jim - Sent from my iPhone - FaceTime! > > On Oct 19, 2013, at 7:52 AM, Karen Hodges <rowantreek@gmail.com> wrote: > > > Hi Jim > > > > Thanks for your comments. I think I am good with the true matches now > > but the false positives can these only be determined by comparing the > > raw DNA when no genealogy match is found and is there a program that can > do this? > > > > Karen > > > > > > On Sat, Oct 19, 2013 at 10:12 PM, Jim Bartlett > <jim4bartletts@verizon.net>wrote: > > > >> Karen > >> > >> In general I agree with Tim. I would add that Triangulation has a > >> very specific requirement: A=B=C=A. That is each pair (AB,AC,BC) must > >> have a shared segment (usually at least 7cM, but perhaps smaller with > >> some risk of a false positive); AND each of these shared segments are > >> significantly overlapping - such that all three - ABC - have, say, at > least the same 7cM. > >> You can accept a little less overlap, by accepting a little more risk > >> that it's not right. With so much randomness in atDNA, we cannot > >> guarantee anything. > > > > ______________________________ > For answers to Frequently Asked Questions about mailing lists, please see: > http://dgmweb.net/MailingListFAQs.html > > > ------------------------------- > To unsubscribe from the list, please send an email to > AUTOSOMAL-DNA-request@rootsweb.com with the word 'unsubscribe' without the > quotes in the subject and the body of the message > > > > > ______________________________ > For answers to Frequently Asked Questions about mailing lists, please see: > http://dgmweb.net/MailingListFAQs.html > > > ------------------------------- > To unsubscribe from the list, please send an email to > AUTOSOMAL-DNA-request@rootsweb.com with the word 'unsubscribe' without > the quotes in the subject and the body of the message >

Karen, I'm not geneticist, but my understanding is that it is small pieces which could be a bit mixed between the parents' chromosmes. Maybe someone else can explain. I was told this by someone with some type of biology degree. E -----Original Message----- From: autosomal-dna-bounces@rootsweb.com [mailto:autosomal-dna-bounces@rootsweb.com] On Behalf Of Karen Hodges Sent: Saturday, October 19, 2013 2:29 PM To: autosomal-dna@rootsweb.com Subject: Re: [AUTOSOMAL-DNA] Family finder matches what to make of them Hi Emily I was wondering what a mish mash of paternal and maternal alleles was? . Your comment is much appreciated. What is HIR short for please? Karen On Sun, Oct 20, 2013 at 3:05 AM, Emily Aulicino <aulicino@hevanet.com>wrote: > Please correct me if I am wrong, but false positives (sadly, a very > general > term) are small segments that are neither identical by descent (IBD) > or identical by state (IBS) and may be a result of the way the > companies are processing the half-identical regions (HIR) information > or they may be a mish-mash of paternal and maternal alleles. > > If two people you match do not match each other, then it is only that > each of those you match are on a different chromosome (these are > different HIRs). > > E > > -----Original Message----- > From: autosomal-dna-bounces@rootsweb.com > [mailto:autosomal-dna-bounces@rootsweb.com] On Behalf Of Jim Bartlett > Sent: Saturday, October 19, 2013 6:17 AM > To: autosomal-dna@rootsweb.com > Subject: Re: [AUTOSOMAL-DNA] Family finder matches what to make of > them > > Karen > > False positives from FF ICW can be determined by asking the two > Matches in question if they match each other on the same segment you match them. > Either > one can confirm it. > > Also you can easily compare them at GEDmatch to see if and how much > and where they share (if they'll upload to GEDmatch). > > Also you can confirm them, one at a time, if they match a close cousin > (your close cousin can confirm the segment if you don't manage their > kit). > > I would never think about comparing raw data. If they won't cooperate > at all (as above), they surely won't give you their raw data, either. > > Jim - Sent from my iPhone - FaceTime! > > On Oct 19, 2013, at 7:52 AM, Karen Hodges <rowantreek@gmail.com> wrote: > > > Hi Jim > > > > Thanks for your comments. I think I am good with the true matches > > now but the false positives can these only be determined by > > comparing the raw DNA when no genealogy match is found and is there > > a program that can > do this? > > > > Karen > > > > > > On Sat, Oct 19, 2013 at 10:12 PM, Jim Bartlett > <jim4bartletts@verizon.net>wrote: > > > >> Karen > >> > >> In general I agree with Tim. I would add that Triangulation has a > >> very specific requirement: A=B=C=A. That is each pair (AB,AC,BC) > >> must have a shared segment (usually at least 7cM, but perhaps > >> smaller with some risk of a false positive); AND each of these > >> shared segments are significantly overlapping - such that all three > >> - ABC - have, say, at > least the same 7cM. > >> You can accept a little less overlap, by accepting a little more > >> risk that it's not right. With so much randomness in atDNA, we > >> cannot guarantee anything. > > > > ______________________________ > For answers to Frequently Asked Questions about mailing lists, please see: > http://dgmweb.net/MailingListFAQs.html > > > ------------------------------- > To unsubscribe from the list, please send an email to > AUTOSOMAL-DNA-request@rootsweb.com with the word 'unsubscribe' without > the quotes in the subject and the body of the message > > > > > ______________________________ > For answers to Frequently Asked Questions about mailing lists, please see: > http://dgmweb.net/MailingListFAQs.html > > > ------------------------------- > To unsubscribe from the list, please send an email to > AUTOSOMAL-DNA-request@rootsweb.com with the word 'unsubscribe' without > the quotes in the subject and the body of the message > ______________________________ For answers to Frequently Asked Questions about mailing lists, please see: http://dgmweb.net/MailingListFAQs.html ------------------------------- To unsubscribe from the list, please send an email to AUTOSOMAL-DNA-request@rootsweb.com with the word 'unsubscribe' without the quotes in the subject and the body of the message

Dear Karen, HIR stands for half-identical region. It is an extremely important term for genetic genealogists interested in autosomal DNA to understand well. Because I couldn't find a good definition for an HIR 9 months or so ago, I wrote my own. It is as follows: Half-identical region: a region of two paired chromosomes where at least one of the two alleles from one person's pair of chromosomes matches at least one of the two alleles from a different person's pair of chromosomes throughout the entire region. A half-identical region may be either identical by descent (IBD) or identical by state (IBS). Some scientists use IBS to mean an HIR. I think things are simpler and clearer if you use the term HIR in the right context and use IBS only for HIRs that are false matches (not the result of a shared common ancestor for the HIR in question). This topic came up on the RootsWeb DNA list in 2009 shortly after 23andMe released Relative Finder. Ann Turner's comments at http://archiver.rootsweb.ancestry.com/th/read/GENEALOGY-DNA/2009-11/12572588 09 are instructive. Sincerely, Tim Janzen -----Original Message----- From: autosomal-dna-bounces@rootsweb.com [mailto:autosomal-dna-bounces@rootsweb.com] On Behalf Of Karen Hodges Sent: Saturday, October 19, 2013 2:29 PM To: autosomal-dna@rootsweb.com Subject: Re: [AUTOSOMAL-DNA] Family finder matches what to make of them What is HIR short for please? Karen