When we calculate your estimate for each ethnicity region based on the AncestryDNA reference panel, we run forty separate analyses. Each of the forty analyses gives another estimate of your ethnicity, and each one is done with randomly selected portions of your DNA. Why forty? Ethnicity estimation can be variable from comparison to comparison -; different combinations of DNA can give us different information, so doing multiple analyses can give us a more accurate estimate, as well as the likely range.
In the example below, we measure an estimate for one person for one ethnicity region. This first chart illustrates that for each of the 40 analyses, a slightly different portion of DNA is analyzed.
This gives us 40 different estimates of a person's ethnicity for each region
Each of the 40 estimates covers a substantial portion of the tested genomic information. Sometimes we find a diverse range of estimates for each region tested.
The Average Estimate
We look at each of the 40 estimates and find the average amount predicted for each region. This average becomes the percent that is displayed in the estimates. Our confidence that your actual genetic ethnicity is EXACTLY the average is not high.
The probable range
There is often a wide range among these 40 estimates. The range shown in the product experience encompasses most of the variability found in the estimates. Our confidence that your actual genetic ethnicity falls within this range is relatively high.
How it looks on screen
The product shows the average estimate as the given percent for each region. The general spread of the 40 estimates is shown as the probable range. Our analysis suggests that your actual ethnicity for this region lies somewhere in this range.
Still curious to understand more? Cool--we're glad you're as interested in genetics as we are. Check out our white paper on ethnicity prediction.