You have three options, since you have two adjustments to do and you can use old or new values for each (but only three because you can't use new values for both).* Adjusting credibility first (i.e. using the old value of the rule's importance to determine the new credibility, then the new value of credibility to determine the new value of the credibility's importance) is the defensive play, and it's generally a good idea to behave defensively.
For example, let's say your neighbor Tim (credibility .5) tells you that there are aliens out to get him (prior probability 1e-10, say). If you adjust both using the old values, you get that Tim's credibility has dropped massively, but your belief that aliens are out to get Tim has risen massively. If you adjust the action first (where the 'rule' is "don't believe in aliens having practical effects"), your belief that aliens are out to get Tim rises massively- and then your estimate of Tim's credibility drops only slightly. If you adjust Tim's credibility first, you find that his credibility has dropped massively, and thus when you update the probability that aliens are out to get Tim it only bumps up slightly.
*You could iterate this a bunch of times, but that seems silly.
Er, any update that doesn't use the old values for both is just wrong. If you use new values you're double-counting the evidence.
Ideally, I'd like to save the world. One way to do that involves contributing academic research, which raises the question of what's the most effective way of doing that.
The traditional wisdom says if you want to do research, you should get a job in a university. But for the most part the system seems to be set up so that you first spend a long time working for someone else and research their ideas, after which you can lead your own group, but then most of your time will be spent on applying for grants and other administrative trivia rather than actually researching the interesting stuff. Also, in Finland at least, all professors need to also spend time doing teaching, so that's another time sink.
I suspect I would have more time to actually dedicate on research, and I could get doing it quicker, if I took a part-time job and did the research in my spare time. E.g. the recommended rates for a freelance journalist in Finland would allow me to spend a week each month doing work and three weeks doing research, of course assuming that I can pull off the freelance journalism part.
What (dis)advantages does this have compared to the traditional model?
Some advantages:
Some disadvantages:
EDIT: Note that while I certainly do appreciate comments specific to my situation, I posted this over at LW and not Discussion because I was hoping the discussion would also be useful for others who might be considering an academic path. So feel free to also provide commentary that's US-specific, say.