by jbeckton » Tue 13 Jan 2009, 18:03:24
$this->bbcode_second_pass_quote('Carlhole', '')$this->bbcode_second_pass_quote('jbeckton', '')$this->bbcode_second_pass_quote('Carlhole', '')$this->bbcode_second_pass_quote('jbeckton', 'P')erhaps you are refering to a point of contention between he and Carlhole. Forgive me but I tend to skim through Carlhole's posts at this point....
What a kunt.
Need I say more?......
Yeah, say some more kunty stuff.
Those that cannot do..... teach. Those that cannot teach......teach gym.-Jack black
by Koyaanisqatsi » Tue 13 Jan 2009, 20:27:41
$this->bbcode_second_pass_quote('emailking', '')$this->bbcode_second_pass_quote('jbeckton', ' ')...
Well, that wasn't what I was saying for which it doesn't matter. You acknowledged the point I thought you were disputing.
This is jbeckton's tactic - once he is pinned down on an argument he plays naive and claims that that wasn't what he was saying at all, and then shifts the debate to a new point (in this case, to the issue of how small must a probability be to constitute very small). Your characterization of my position above is 100% correct. If that wasn't what JBeckton meant, then why would he respond to
$this->bbcode_second_pass_quote('jbeckton', '
')$this->bbcode_second_pass_quote('', 'Y')ou are still left with two very unlikely events occurring together, yielding an even smaller probability. As an engineer I think you would know that.
You are incorrect; the probability of a collapse increases exponentially after the fire has started because the events are not independent. Do you really not see this?
by Koyaanisqatsi » Tue 13 Jan 2009, 20:34:59
$this->bbcode_second_pass_quote('jbeckton', '')$this->bbcode_second_pass_quote('Koyaanisqatsi', '
')
You are incorrect; the probability of a collapse increases exponentially after the fire has started because the events are not independent. Do you really not see this?
Yes, the probability of collapse increases after the building is set on fire, therefore:
P(B) does not equal P(B|A)
That's not the claim. For the thousandth time, you are confusing P(A and B) with P(B|A). See my response to emailking.
$this->bbcode_second_pass_quote('Koyaanisqatsi', 'I')t doesn't matter whether one uses the equation for dependent or independent events if P(B) or P(B|A) is sufficiently small:
$this->bbcode_second_pass_quote('', '
')This is an assumption you have made (you know what happens when you make assumptions). I have done probability (PRA) studies for nuclear power plants that have probabilities 10^(-6) and smaller which is certainly <<1, are you saying we should ignore them? The NRC says they are significant, I agree.
Have you made any attempt to quantify P(B) and P(B|A) before assuming the difference is negligible? I bet you haven’t.
Guess you are just going with “since the probability <<1 it must be impossible".
Well sorry to say that events with a probability <<1 occur everyday. For instance you chances of dying in a plane crash are 11 million to 1 or 9.1e-8
Guess we can assume that no one ever dies in a plane crash since P<<1 right? I wonder what the probability of dying in a office building from an airplane impact would be?
Guess its impossible?
by jbeckton » Wed 14 Jan 2009, 20:01:48
$this->bbcode_second_pass_quote('ROCKMAN', 'I') love debates about statistics! It allows me to ask my favorite stat question: if you flip a quarter 19 times and it comes up heads every time, what are the odds that it will come up heads on the 20th flip? This was the question asked the first day of class by my first stat instructor.
50/50
Those that cannot do..... teach. Those that cannot teach......teach gym.-Jack black
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by jbeckton » Wed 14 Jan 2009, 20:09:47
$this->bbcode_second_pass_quote('Koyaanisqatsi', '
')I have clearly been saying - multiple, multiple times - that "P(A and B) < P(B)" and JBeckton responds each time with "P(B|A) > P(B)", which is a strawman, because I have never said otherwise.
Nor have I ever claimed that P(A and B)>P(B) or P(A) which you keep implying.
I only claimed "P(B|A) > P(B)"
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by Koyaanisqatsi » Thu 15 Jan 2009, 20:24:58
$this->bbcode_second_pass_quote('jbeckton', '')$this->bbcode_second_pass_quote('Koyaanisqatsi', '
')I have clearly been saying - multiple, multiple times - that "P(A and B) < P(B)" and JBeckton responds each time with "P(B|A) > P(B)", which is a strawman, because I have never said otherwise.
Nor have I ever claimed that P(A and B)>P(B) or P(A) which you keep implying.
I only claimed "P(B|A) > P(B)"
Fine - I was suggesting that because I don't see how
$this->bbcode_second_pass_quote('', 'Y')ou are still left with two very unlikely events occurring together, yielding an even smaller probability.
can be interpreted otherwise. By probability of two events occurring together, I mean P(A and B), not P(B|A). Saying that the statement is invalid because P(B|A) > P(B) is a strawman because I have never suggested that this might not be the case.
Let's start with a clean slate. If we let A=a 9/11 scale terrorist attack(+consequent fires) and B=fire-induced progressive collapse, then the probability of BOTH terrorist attack AND fire induced progressive collapse is:
P(A and B) = P(A)*P(B|A)
correct?
by jbeckton » Thu 15 Jan 2009, 21:35:06
$this->bbcode_second_pass_quote('Koyaanisqatsi', '
')Let's start with a clean slate. If we let A=a 9/11 scale terrorist attack(+consequent fires) and B=fire-induced progressive collapse, then the probability of BOTH terrorist attack AND fire induced progressive collapse is:
P(A and B) = P(A)*P(B|A)
correct?
Yes
And I would also agree that we are left with a “very unlikely event” but I do not agree that this should be enough evidence to show that 911 was in any way a conspiracy, only that a “very unlikely event” occurred.
But as we all know, “very unlikely” is open to interpretation and “very unlikely” events occur every day just as we saw in the Hudson River crash today. There is approximately a 1:11000000 chance of this occurring to any person and it happened to a few hundred just a few hours ago.
I am sure that “very very unlikely” won’t comfort them very much should they ever fly again.
Those that cannot do..... teach. Those that cannot teach......teach gym.-Jack black
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by Koyaanisqatsi » Mon 19 Jan 2009, 15:09:57
$this->bbcode_second_pass_quote('jbeckton', '')$this->bbcode_second_pass_quote('Koyaanisqatsi', '
')Let's start with a clean slate. If we let A=a 9/11 scale terrorist attack(+consequent fires) and B=fire-induced progressive collapse, then the probability of BOTH terrorist attack AND fire induced progressive collapse is:
P(A and B) = P(A)*P(B|A)
correct?
Yes
And I would also agree that we are left with a “very unlikely event”
So do you agree with this or not?
$this->bbcode_second_pass_quote('', 'Y')ou are still left with two very unlikely events occurring together, yielding an even smaller probability.
by jbeckton » Mon 19 Jan 2009, 22:06:14
$this->bbcode_second_pass_quote('Koyaanisqatsi', '')$this->bbcode_second_pass_quote('jbeckton', '')$this->bbcode_second_pass_quote('Koyaanisqatsi', '
')Let's start with a clean slate. If we let A=a 9/11 scale terrorist attack(+consequent fires) and B=fire-induced progressive collapse, then the probability of BOTH terrorist attack AND fire induced progressive collapse is:
P(A and B) = P(A)*P(B|A)
correct?
Yes
And I would also agree that we are left with a “very unlikely event”
So do you agree with this or not?
$this->bbcode_second_pass_quote('', 'Y')ou are still left with two very unlikely events occurring together, yielding an even smaller probability.
Those that cannot do..... teach. Those that cannot teach......teach gym.-Jack black
by Koyaanisqatsi » Tue 20 Jan 2009, 04:00:28
$this->bbcode_second_pass_quote('jbeckton', '')$this->bbcode_second_pass_quote('Koyaanisqatsi', '')$this->bbcode_second_pass_quote('jbeckton', '')$this->bbcode_second_pass_quote('Koyaanisqatsi', '
')Let's start with a clean slate. If we let A=a 9/11 scale terrorist attack(+consequent fires) and B=fire-induced progressive collapse, then the probability of BOTH terrorist attack AND fire induced progressive collapse is:
P(A and B) = P(A)*P(B|A)
correct?
Yes
And I would also agree that we are left with a “very unlikely event”
So do you agree with this or not?
$this->bbcode_second_pass_quote('', 'Y')ou are still left with two very unlikely events occurring together, yielding an even smaller probability.
by jbeckton » Wed 21 Jan 2009, 19:46:20
$this->bbcode_second_pass_quote('Koyaanisqatsi', 'A')ccording to YOUR definition
Like most engineers, I don't really like terms like ‘very’, ‘nearly’, ‘really’…etc
My definition of "very low" for this case:
P(A)*P(B|A)
Those that cannot do..... teach. Those that cannot teach......teach gym.-Jack black
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by Koyaanisqatsi » Fri 23 Jan 2009, 03:02:02
$this->bbcode_second_pass_quote('jbeckton', '')$this->bbcode_second_pass_quote('Koyaanisqatsi', 'A')ccording to YOUR definition
Like most engineers, I don't really like terms like ‘very’, ‘nearly’, ‘really’…etc
My definition of "very low" for this case:
P(A)*P(B|A)
Okay, from this and from your earlier statements I take it that you think that either P(A) and/or P(B|A) is not very unlikely, correct?
