My question is how can I create my own probability functions ?
For example , take a look at this article at medium. At some point it produces
$$ P1 = (1 - q) + (qP1^2) $$
Which is the probability if a drunk man will fall from a cliff.
How the writer reaches to the conclusion that has to multiply q with $P1^2$ ?
Are there any resources(books, papers) that teaches (or have examples) someone how to produce this functions-this kind of solutions ?
I want to understand this problems and solutions but I cant find something relevant on the web. Thanks
Answer to my first question
On "Random Walk: Drunk Man in a Cliff" Problem, Why $qP$ in the equation $P = p + qP^2$?