What makes it unbelievable that Boston flooded with molasses is the implied scale. The article is about several blocks flooding, not about “Boston” flooding; the original claim remains unbelievable.
Also, but unrelated, you need to remember that if other statements can increase credibility, they can also reduce it. If you told me Boston was flooded with molasses on the scale implied by that statement, and then directed me to a site that had some good articles but also promoted perpetual motion machines, I wouldn’t give the claim any more credibility. It is true that nobody would make all that stuff up for a joke, but people can make up huge quantities of stuff under self-delusion.
if other statements can increase credibility, they can also reduce it.
Sure, but it’s utterly unsurprising that there exists a B such that P(A&B) P(A) is more surprising, which is why I’d asked for an example of what DanielLC had in mind by it.
Your probability theory here is flawed. The question is not about P(A&B), the probability that both are true, but about P(A|B), the probability that A is true given that B is true. If A is “has cancer” and B is “cancer test is positive”, then we calculate P(A|B) as P(B|A)P(A)/P(B); that is, if there’s a 1/1000 chance of cancer and and the test is right 99⁄100, then P(A|B) is .99.001/(.001.99+.999.01) which is about 1 in 10.
I suppose, given the context, I should say out loud that it wasn’t me, both because I don’t find it downvoteworthy and because I make a practice of not downvoting comments that reply to mine or that I reply to.
I endorse not trying to read much into one or two downvotes… the voting behavior of arbitrarily selected individuals in a group like this doesn’t necessarily mean much.
The way to fix the formatting is to use a \ in front of the asterisk whenever you want to actually display it. This is also necessary for underscores, which some people use in their usernames.
I didn’t downvote it, and don’t have interesting speculation as to why it was downvoted.
What makes it unbelievable that Boston flooded with molasses is the implied scale. The article is about several blocks flooding, not about “Boston” flooding; the original claim remains unbelievable.
Also, but unrelated, you need to remember that if other statements can increase credibility, they can also reduce it. If you told me Boston was flooded with molasses on the scale implied by that statement, and then directed me to a site that had some good articles but also promoted perpetual motion machines, I wouldn’t give the claim any more credibility. It is true that nobody would make all that stuff up for a joke, but people can make up huge quantities of stuff under self-delusion.
Sure, but it’s utterly unsurprising that there exists a B such that P(A&B) P(A) is more surprising, which is why I’d asked for an example of what DanielLC had in mind by it.
Your probability theory here is flawed. The question is not about P(A&B), the probability that both are true, but about P(A|B), the probability that A is true given that B is true. If A is “has cancer” and B is “cancer test is positive”, then we calculate P(A|B) as P(B|A)P(A)/P(B); that is, if there’s a 1/1000 chance of cancer and and the test is right 99⁄100, then P(A|B) is .99.001/(.001.99+.999.01) which is about 1 in 10.
Can anyone explain why the parent was downvoted? I don’t get it. I hope there’s a better reason than the formatting fail.
I suppose, given the context, I should say out loud that it wasn’t me, both because I don’t find it downvoteworthy and because I make a practice of not downvoting comments that reply to mine or that I reply to.
I endorse not trying to read much into one or two downvotes… the voting behavior of arbitrarily selected individuals in a group like this doesn’t necessarily mean much.
The way to fix the formatting is to use a \ in front of the asterisk whenever you want to actually display it. This is also necessary for underscores, which some people use in their usernames.
I didn’t downvote it, and don’t have interesting speculation as to why it was downvoted.
That’s fair.