Since not everyone thinks my approach is totally wrong like it seemed in the beginning I will re-enter this discussion although I said that I would abandon the approach. I did plan to abandon it, not because I understood why it was completely wrong but because I saw the massive dislike of it as enough evidence to believe it is wrong.
Concerning 1)
As I mentioned my point was not to do nothing, try to analyse and then come to some kind of result whether another person likes you. It is to assign probabilities on whether that person has a crush on you in order to decide how to act.
Concerning 2) If you decide to do certain things in the process of flirting you always assign probabilities to whether to person has a crush on you or not. If this would not be the case than there would be no development in the flirting process. You would give exactly the same signals at the beginning and at the end. You only progress to more obvious signals because based on what you have seen before you think it is more probable that that person likes you. The only question is do you let your subconscious assign the probabilities or do you make a conscious effort to do that. Most people will let their subconscious assign the probabilities. I agree that a lot of people will find it creepy if I decide to make conscious decisions here, but A) I do not have to let them know that I make a conscious decision and B) those people would probably also have problems with me making conscious decisions on other issues where they do not and if a person is not willing to accept that that is how I make my decisions it is probably the wrong person anyway.
Concerning 3) yes my attractiveness something specific to me. But my attractiveness is not the only factor deciding how likely it is for someone to have a crush on me. I am not sure how to explain this properly, but in a world where every person would only have a crush on someone once in his/her entire life the chance of someone having a crush on me would be lower than in a world where people on average have a crush on a hundred people during their life. In the second world there are just way more crushes to be distributed and I don’t see why regardless of my attractiveness I should not get more of them. Therefore I think it is relevant to know how many crushes other people have in general. Of course I cannot say that the prior for someone having a crush on me is the same as the average prior of people having a crush on other people in general. But my believe about the prior for myself should be related to the average prior.
If you have a crush on someone you usually want to find out if they have one on you too. In my opinion outright asking them is often not a good solution, because if they don't have a crush on you yet it decreases the chance of this ever happening if they know you have one. This believe is based on what I read about love psychology. Hovever I don't really want to discuss the option of outright asking them in this thread, therefore I have not elaborated further how I got to this believe.
The alternative to asking them is trying to interpret signals that they might give you. However to know how many signals you need before you should believe that they are in love with you, you would need the prior. I have not been able to find anything about the prior of someone being in love with you. Therefore my Idea is to do a survey in order to find out how likely it is that a person you know has a crush on you. The plan is to ask the person taking the survey how many people they know well enough to possibly have a crush on them and how many people they actually have a crush on.
I have created a Survey for this and would be really happy if you would participate.
The next stepp would be to discuss how certain signals a person can give you raise the probability of them having a crush on you. That part is quite difficult. I think probably the best way would be to check how your friends react to certain situations and what body language they show you and then, if you find out someone has a crush on you, to look up what he did differently from people who are merely your friends. I am currently not in a good position to do this experiment but if someone wants to try or has results about this to share please do so. However I think this part is less important than finding the prior, because most people have at least a general idea about what certain signals mean from personal experience while at least I have no idea at all what the prior might be.