Your explanation has almost clarified it for me. Without complicating the issue and to get a better understanding, under what circumstances would the number of distinct records be greater than the number of unique records? The Database statistics in general for each year/event shows the number of distinct records to be greater than the unique records. Allan Raymond -----Original Message----- From: Dave Mayall <dave@research-group.co.uk> To: FREEBMD-DISCUSS-L@rootsweb.com <FREEBMD-DISCUSS-L@rootsweb.com> Date: 03 February 2004 08:36 Subject: Re: Latest update >----- Original Message ----- >From: "John Fairlie" <john.fairlie@blueyonder.co.uk> >To: <FREEBMD-DISCUSS-L@rootsweb.com> >Sent: Monday, February 02, 2004 5:50 PM >Subject: RE: Latest update > > >> OK, I give up. Please explain "distinct" records as opposed to "Unique" >> records. > >:-) > >We implemented a solution to solve the overcounting that you identified! > >Consider a page of 40 entries, double keyed, with 3 entries transcribed >differently by the transcribers. > >That would be 80 total records, it would also be 43 unique records, giving >an overcount of 3 records to the total, and messing the stats up. > >We now analyse the alignment of unmatched records, and do an additional >count on records which don't actually match, but which (because of their >sequence) are obviously different transcriptions of the same entry, and in >the distinct records count, onlyu count them once, thus there would be 40 >distinct records. > >This achieves two things; >1) More accurate stats >2) Data that tells us about the degree of mismatch between double keyings >(the difference between Unique and distinct is the number of mismatches) > > > >============================== >Gain access to over two billion names including the new Immigration >Collection with an Ancestry.com free trial. Click to learn more. >http://www.ancestry.com/rd/redir.asp?targetid=4930&sourceid=1237