It's been proven so many times now that I should just include it in the Fundamental Truths of Life: You cannot listen to NPR for more than 30 seconds before hearing some asinine comment that requires you to refute it aloud.
It happened again this morning. Two guest experts in cyber-security were commenting on a listener question. The listener, Woman X, was talking with her friend, Woman Y, about a new accessory on Y's phone. Later that day, X saw an ad for that accessory on her Facebook feed. She wanted to know if her phone overheard the conversation and influenced which ad she saw.
The first cyber-security expert answer the question correctly, which is to say, he said no. He started talking about confirmation bias, where you notice things that support your pre-existing world-view and don't notice conflicting evidence as readily. But then the other expert interrupted him to say she had to disagree. And why did she have to disagree? Because she'd "seen this happen too many times" and she'd even had this happen to her. She said (paraphrasing), "When you ask the large data companies they say, 'Well, technically that can't happen, but....'"
This is baseless speculation that, when done by a news entity NPR doesn't like, NPR calls "fake news." I can immediately think of two non-crazy explanations for what happened.
POSSIBILITY 1: COINCIDENCE. If Y bought something recently, the chances are many people in America are buying that thing right now. And the types of things you see advertised are the types of things many people are buying right now. It's not a conspiracy when you see new products enter the marketplace, which is what X is experiencing.
POSSIBILITY 2: HOW MARKETING WORKS. Y bought the new item, which is recorded in Y's consumer profile. Companies buy access to these profiles, and they buy access to social media connections. The manufacturer of the new item could have paid Facebook to advertise the new item to the friends of people who recently bought the item. Creepy and frustrating, but not a violation of privacy.
Here's the thing: when the cyber-security expert said large data companies tell her these things can't happen "technically," since they are technology companies, they are saying these things can't happen. They're saying it this way to be nice, but they are essentially saying, "Crazy lady, your idea is insane." It reminds me of the scene from Dumb & Dumber when Lloyd hears "one in a million" and says, "So you're telling me there's a chance!"