BAE

Given P(she smiles at you | she likes you) is approximately 1

Assuming P(she likes you) > 0

Then we can sub into

P(she likes you | she smiles at u) = (P(she smiles at you | she likes you) * P(she likes you))/P(she smiles in general)

To get P(she likes you | she smiles at u) = x/P(she smiles in general)

Where x is some number between 0 and 1

Therefore we can conclude the more she smiles the less likely its cos she likes you. Therefore find the oens who dont smile and get em to smile. Therefore bigtiddygothgf.

unfortunately, P(she likes you) ≈ 0

Nice, we can also assume that P(she smiles at you | she likes you) is approximately 1, simplifying to only 2 variables, and also substitute P(you are likable) for P(she likes you) to remove all unknowns.

Damn you priors

You seem to confuse "someone likes you" with "someone finds you attractive". Maybe someone smiles at you just because you seem like a nice person. I would even argue that this happens much more frequently than someone smiling at you because they find you attractive.

Well, this is aimed at straight dudes in any case, so in this mindset "girls" (!!!) only either are for sex or unimportant.

So lowest denominator possible (rarely smiles)?

I'd be a lot less confused by a Venn diagram.

P(she only has a facial paralysis)

Alternatively

P(she smiles at you| she likes you) but..