Facebook Algorithm Suggested Posts?

How are Facebook suggested for you posts decided? I have someone who I think is looking at my profile…I don’t look at his…. but he has an extremely boutique Italian custom bike and I am getting suggested posts about that kind of bike and a few of his other extreme niche hobby’s? Is it purely coincidence I’m getting ads that should be targeted to him and not me? And no I don’t google or search any of this stuff I don’t have any other remotely similar interests. And no I am not creeping his profile which is the weird part that I get targeted ads for him…

Facebook Algorithm Suggested Posts?
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