Address Quality – Take 2
By David Loshin
The intended recipient must be associated with the deliverable address.
The problem here is no longer address quality but rather address
The address may be complete, all the elements may be valid, the
ZIP+4 is the right one, and all values conform to standardized abbreviations …
and still be incorrect if the recipient is not associated with the
This is the bigger challenge with address data quality, since address
correctness or accuracy is a factor of real-world events that are not
necessarily synchronized with your databases. Some level of control is again
served by the Postal Service through the NCOA (National Change of Address) data
set that is licensed to tools providers.
Checking against the NCOA data set will notify you if an entity linked to a
location has self-reported a change of address, and this accommodates a large
portion of the address correction issues. However, there are estimates about the
percentage of people that moved, and I recall reading a Census Bureau press
release about their 2006-2007 statistics noting that 14% of the population moved
over the year.
Not all changes propagate to the NCOA file at the right time, and it may take a
while before all consumers of that data actually synch up with the NCOA data
set. Even if you do a quarterly review, if we trust that 14% statistic, then
there is a pretty good chance that by the end of the quarter you will still have
a 3-4% inaccuracy rate for mapping entities to locations.
And there are other considerations that are not incorporated into this
calculation. For example:
• Individuals change jobs and therefore change business addresses
• Third-party data vendors incorrectly link individuals to locations
• Miskeyed data
• Purposely incorrect data
• Propagation of legacy addresses overwriting updated addresses
This a small sample of challenges. But what it means is that there are many
aspects of assessing and assuring the quality and correctness of addresses, and
it may be worth reviewing the ways that your organization verify, validate,
standardize, and correct location data!