(March 4, 2011 at 8:56 pm)fr0d0 Wrote: Data = the bibleTHAT just shows me that you haven't understood the concept at all. You have to point to evidence about the world, say for example the medical case I used in the Chat room, 1% of people have disease x and 90% of people who have disease x will test positive. the 99% of people who do not have the disease have a 15% chance of a false positive, given that person y tests positive for disease x, what are the chances that they actually have the disease?
This sort of analysis will show that one of the two scenarios, having the disease or not having the disease, is more likely give the evidence (the % of people infected, the chances of testing positive if you have the disease and the number of false positives) and thus you are only justified in believing the thing that has the highest probability of being true.
I suggest you go look at some videos on youtube if you want to come to terms with how it works.
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