Denise, I went through the same feelings of unease when using the 23andMe tools vs the FTDNA analysis tools. What changed that all about was Rob Warthen's DNAgedcom.com utility. Since I can now download all of my CB matches for the accounts I manage on FTDNA, and I can also download the data files from 23andMe for those accounts as well into spreadsheets, * * *23andMe is the clear winner (IMHO) for ICW analysis* -- but with caveats. The most useful file in the 23andMe set is the AF file, which shows at the chromosome level, those with whom you share genomes and public matches by name (all others are Anonymous###, where ### is a number up to 0999 in my case) and those whom have filled out the birthplaces of the grandparents in the Countries of Ancestry Survey. Those are the caveats. That is, someone has to either have listed their profiles as public matches or shared genomes, but all have to fill out the CofA survey. Since I have a multiple profile 23andMe account I get a very large csv AF file -- usually North of 25 mB to download from DNAgedcom.com -- with all of the chromosome level matches for all of my profiles at one swell foop...er...fell swoop. This results in a very large spreadsheet when opened in Excel (of late 177,829 rows by 15 columns). {Note: my computer's ability to handle these large data arrays improved remarkably, when I switched to a 64-bit machine (running Windows 8) with 12GB of RAM and most importantly installed a 64-bit version of Excel. Most of my Excel demons went away with that change. I could even run Tim Janzen's manual phasing routine for three raw data arrays with no problems whatsoever after installing the 64-bit Excel.} The first thing I do is to open the csv file from 23andMe on DNAgedcom.com and then "Save as" an .xlsx file immediately. Otherwise Excel will complain of data loss, if you start to customize the file while in .csv form and then save it later. Next, I generally either delete or hide eight of the columns (C to J) in the 23andMe AF spreadsheet namely: MaternalGrandmotherBirthCountry, MaternalGrandfatherBirthCountry, PaternalGrandmotherBirthCountry , PaternalGrandfatherBirthCountry , MaternalGrandmotherDeclaredAshkenazi, MaternalGrandfatherDeclaredAshkenazi, PaternalGrandmotherDeclaredAshkenazi , and PaternalGrandfatherDeclaredAshkenazi. Sometimes I also delete the SegmentLengthInMegaBasePairs column (column N) as well as it is really not needed. Then I quickly shorten the names of the remaining columns from Chromosome, SegmentStartInMegaBasePairs, SegmentEndInMegaBasePairs, and SegmentLengthInCentiMorgans to Chr, Start, End, and cM. This clean up sounds like a lot, but it actually takes less than 30 seconds to do all of it. In this example, the above dimensions of the abridged worksheet are now 177,829 rows by 6 columns and contain the Ancestry Finder profiles of all seven people in my account along with all of their individual matches and everyone with whom we are sharing genomes! Lastly I highlight all the remaining columns and then set Filters on all of them. The Filter function is a most wonderful tool! It allows one to cull and highlight data in an amazing variety of ways. I usually set the cM filter to >7 cm, and set the Matchname filter to "Does not contain" Anony*, where the * is a wildcard. This removes a thousand Anonymous entries and a great deal of the IBS entries, which in my example above amounts to 65,588 entries > 7 cM. Setting the cM filter to >11 is even more effective in getting rid of superfluous entries and reduces the total to some 53,705. This is a far cry from the original 177,829 rows. Sorting the cM column from largest to smallest then allows one to focus on the most significant matches. Increasingly, I am finding that I rarely get anything of value from pursuing smaller matching segments. These small block matches are to more distant cousins, who when contacted usually do not know their pedigrees very far back. And even if one or two descent lines are known, there remain many gaps in the other lines. Similar efforts are required to pursue these small matches as compared to the larger, more significant blocks. While there is give and take in terms of data sharing, I find that some people want you to do their genealogy for them as opposed to sharing data in common pursuit of pedigrees. My advice is to pick the low hanging fruit first and then if there is a multiple match on a given segment, pursue the smaller block matches last. When I identify a block on a chromosome that I want to work on, I then limit the Chr column filter to that specific chromosome only.** _ __As long as you are sharing genomes or the match is public listed on 23andMe, you can see all of their matches as well._ The net result is that you get a true, chromosome level, block specific match display. A true and very useful "In Common With." In this regard, the 23andMe AF data + DNAgedcom.com beats FTDNA hands down even with their recent "improvements." (The shame of it is that it would be so easy for FTDNA to trump this with a few simple and long sought changes: 1.) A true, specific chromosome level ICW, and 2.) a way to download all CB data of that ICW match to an Excel spreadsheet.) ****** It is also possible to put together in one uniform worksheet, the results of an FTDNA CB download and the 23andMe AF data with common matches shown in one worksheet. I do that quite frequently. The caveat there is that you need at least two people who are on both platforms to make the ICW really work and then because one cannot see if there is an A=B=C match in the FTDNA data, that is the only lame thing in those displays. (FTDNA are you listening? Rebeka? Anyone?) I have had some really notable successes in doing this. Recently I triangulated a Chr 4 block to one set of my great great great grandparents, with some 14 people identified either on 23andMe and/or FTDNA who match! There were 11 original but since doing the initial correlation, three more have shown up from the 23andMe AF matches. Three of this set of 14 triangulate to 4C and one to 4C2R, with the balance undetermined, but definitely connected. There is one known NPE and one adoption in the group of 14, BTW. This is an on-going project and I anticipate another report in coming months, which is only waiting for some of the slow or no responders to get back to me. Based on more recent work, I have hints and a hunch, that I may be able to identify to which of the ancestral couple this block of common DNA on Chr 4 is owing! And a further lead on yet another block on Chr 18 which may be owing to the other partner of the ancestral couple. If I can sanitize my initial analysis report of personal names, I would be willing to share a copy of that as a Word File on request. Walter ** I have a simple filter routine that I also perform on the Start and End settings of an individual block, which shows only those people who match both me and if they match one another or not. I am stopping short here of describing that procedure owing to the length of this post. However, I will explain in detail how that works on request (on or off list as you prefer.) On 11/16/2013 8:28 PM, Denise Sproed wrote: > On Family Tree DNA one can 'triangulate' for 'in common matches' (not > necessarily in common on the same chromosome)... > > Does 23andme have a similar tool? Or do folks all download the data from > www.dnagedcom.com so they can manually review which people match on a > specific chromosome? > > I am aware Family Inheritance Advanced lets you compare 3 people to another > but that doesn't tell you who ELSE in the list might share that same > chromosome location... > > Denise > >