Imagine that at different points in time, the confidence in your persona can be quantified. Say at some point in time last year they were 89% confident of the type of person you were, but today after months of using a ton of random fake likes and clicks they are only 16% sure.

They could choose to ignore low confidence measurements and still assume you are the same person from that point in time last year. Given that they can measure the standard rate of change in people’s interests (per interest even), and how quickly interests fall out of style, they can then extrapolate how relevant certain ads might be for you today based on your old data.

Imagine that. They don’t just own your data today, they own all the forecasts of your data for years to come. Go home and sleep on it.

What if the person who gleefully shared everything on social media, and the person who hides their trail actually are different? People change their beliefs and spending habits all the time. It why we look back on our own writing from years ago and cringe.

The best solution is to just not use Facebook.

Better if you can get your account suspended for something that doesn't provoke a law enforcement response.

Agreed, if you don’t want them to have data on you the best case is to never use anything FB owned, including Instagram and WhatsApp.

If you already use FB services, stop using them and don’t give anymore data. They will still know about you, but at least you won’t give them any new information.

But do they actually do that? It seems like a lot of effort to market to someone who's less likely to be successfully marketed to.

Unless you are mentally disabled in some way, anyone can be successfully marketed. People like to believe they are special snowflakes that can rise above the influence of marketing, but hit them with the right marketing message and you got them.

> People like to believe they are special snowflakes that can rise above the influence of marketing, but hit them with the right marketing message and you got them.

Maybe so, but the success of marketing has different probabilities for different individuals. So, if you're Facebook, it wouldn't make sense to invest in de-poisoning poisoned tracking data if they'd have a low chance of success with their marketing messages. Also, I'm doubtful any de-poisoning technique is perfect, so the resulting profile is probably worse for targeted marketing, all else being equal, as well.

Right, that’s why the only way to win is not to play, there is no safe level of exposure to Facebook or Google.