The calculations are deterministic. I happen to know how astrologers work, and why people still believe them.
You run the algorithm using the exact time and place of client's birth. This is, of course, bullshit — some random predictions, which are deliberately written in quite ambiguous, but somewhat flattering style (the genre was perfected in hundreds of years). But now, the most interesting part comes to play.
You tell the client one or two predictions from the list, starting from the most vague and/or flattering (like "you are probably going through worse times than you deserve"), and observe the reaction. If it is positive, you probe the next close thing from the generated set, and so on. If you are good in reading people and adjusting your response according to body language feedback, you can generate the set of predictions or advices so accurate you will impress even yourself, even if you don't believe any of the astrological bullshit. Most astrologers don't.
You run the algorithm using the exact time and place of client's birth. This is, of course, bullshit — some random predictions, which are deliberately written in quite ambiguous, but somewhat flattering style (the genre was perfected in hundreds of years). But now, the most interesting part comes to play.
You tell the client one or two predictions from the list, starting from the most vague and/or flattering (like "you are probably going through worse times than you deserve"), and observe the reaction. If it is positive, you probe the next close thing from the generated set, and so on. If you are good in reading people and adjusting your response according to body language feedback, you can generate the set of predictions or advices so accurate you will impress even yourself, even if you don't believe any of the astrological bullshit. Most astrologers don't.