In terms of evidence the hypothesis about UFOs has a sharp contrast to the hypothesis of AI. There are thousands of empirical evidences about UFO sightings. However Bayesian interference (increase the credibility) of each of the evidence is very small. That is, most of these evidences have an equal probability of being true or false and do not carry any information. Note that if we have 20 evidences with a probability of truth greater than 50%, say 60%, then Bays formula give a very substantial total evidence of 3000 to 1 - that is, would increase the validity of a priori hypothesis of 3000 times.
This is not how that theorem works. You can’t assume that each observation has a 50% chance of being an actual alien entity. I’m not sure if this is what you are saying. If it is then I’m very confused about how you are trying to use Bayes’s theorem.
He’s talking about the likelihood ratio P(sighting|aliens)/(P(sighting|aliens) + P(sighting|no aliens)), which is a good measurement of the evidence gained from a sighting.
He’s talking about the likelihood ratio P(sighting|aliens)/(P(sighting|aliens) + P(sighting|no aliens)), which is a good measurement of the evidence gained from a sighting.