Note: Act quickly. Looks like you can still get a free book courtesy of SAS from here.
The New York Times features Acxiom, one of several data vendors that purportedly know a lot about you and me. Other key names in this sector include Experian and Equifax. What's new is that Acxiom will allow consumers to proactively "correct errors", or at least learn what is being bought and sold behind our backs.
I have dealt with all three of these companies. They are pretty much the same business. Here are some points to note about this news:
1. AboutTheData.com only deals with marketing data. Acxiom sells data to all kinds of parties, like credit card companies, insurance companies, and presumably government agencies. You cannot edit those data. The article gives examples of data that won't be made available: whether a person is a “potential inheritor” or an “adult with senior parent,” or whether a household has a “diabetic focus” or “senior needs.”
2. Marketing data are mostly harmless. When they get it wrong, you may have different kinds of offers or marketing materials sent to you, or you may receive a different price on a good than intended. The data that are sold to insurers and government entities are likely to impact your life more heavily but they are not being exposed in this program.
3. You are allowed to edit your data but the option to delete your profile is not available. Opting out of sharing is not the same as deleting the data.
4. Just like every report I have seen about "correcting data", the reporter just assumes that the only things being edited are "errors". Not true. Since the data represent you to external parties, there is an incentive to create a fictional self. This type of error correction measure is very likely to cause even more distortion in the data. It encourages gaming. I last wrote about this issue here.
5. At the individual level, much of this data is guesswork. In technical terms, they are "modeled". The data provider has actual data on a sample of people, and then try to guess what everyone is like. Even something as basic as gender might be guessed. Your name is used as a clue, so is your neighborhood and other things like religion. If you have an unusual name, the guess can be wrong. This type of data is valuable when used with some level of aggregation; it is not to be trusted at the individual level.