Note: For those of you who love the old search, it is still there. You can get to it by clicking “Old Search” in the tan bar on top of the search pages or here: Old Search. Old Search has always been there. The lifespan filter was applied to both and other than that we have not changed anything with either new or old search.
When you use lifespan filtering and date ranges, there is a small bug that will omit a few records.
Let’s say that you searched for John Smith, born in 1849 and you asked search to apply a range of +- 2. With a fudge factor (fudge factor is 5), you would expect the range of birth dates in records returned would be:
1842-1856 (1849 -5 -2) to (1849 +5 +2)
So our search engine will check the following on all records that match the name John Smith or some variation of John and/or Smith:
- If a record shows evidence that a person lived before 1842, it discards the record
- It checks to make sure that the record does not refute the idea that a person was born between 1842 and 1856. So if the record says the person was born in 1841 or 1857, it throws that record out.
- Then the search engine checks to make sure that the record fits in the lifespan, ie, if a person has a high range of 1856 for a birth date, then we assume that they could not have been alive after 1957 (1856 + 2 year fudge), so a record showing the person died in 1975, would be thrown out.
So the part that wasn’t working quite right? #2.
The fix has been determined and should be live on the site sometime tomorrow morning (May 6) on the west coast (US), noon-ish, on the east coast (US), and late evening in Europe.