Was Lee Oswald the passenger in Whaley's Taxi?

[John Mytton]

They can not be dependent. Oswald's position in each lineup can be any one of four. Each witness has a 1/4 probability of a random correct pick.

Do you dispute the 6 eyewitnesses 1 in 1024 chance of all randomly picking Oswald?



JohnM

[John Iacoletti]

Nobody claimed that the lineup picks were random events.  Nor were they even independent events.  That's where your statistical analysis fails.

[John Mytton]

Nobody claimed that the lineup picks were random events. 

Well duh, of course there was nothing random about picking Oswald, he was the man they all saw.



JohnM

[John Iacoletti]

Well duh, of course there was nothing random about picking Oswald, he was the man they all saw.

I know that's what you believe, but your bogus argument here is that either Oswald was the man they all saw, or they all randomly picked the same guy.

[John Mytton]

As you state it yes, they are four times worse.

Like six persons rolling a four-sided dice looking for exactly one combination.

Probability of choosing the same number

Q. Assume n people choose a number between 1 and k uniformly at random, simultaneously. What is the probability that any two of the n people get the same number?
I tried: The probability that two people choose the same number is 1k. There are (n/2) different pairs. How to proceed from this?

Thanks.

A.
https://math.stackexchange.com/questions/509679/probability-of-choosing-the-same-number




Probability of choosing same number

Q. There are four friends ? Adam, Bella, Christopher and Drew. All of them are asked to choose any number in their mind. Now what is the probability that every one of them has the same number in mind? The chosen number must be in between 1 to 5 (including 1 and 5).

A1. Without loss of generality, let's say Adam picks first. The probability that the other 3 choose the exact same number as Adam is 1/5∗1/5∗1/5, which gives the result of 1/125.

Note: this answer presumes that the numbers are chosen at random.

A2. Another way to see the problem.
Total number of outcomes when 4 people are free to choose a number between 1 and 5 are equal to 5^4 (or 625)
Outcomes when everyone chooses the same number are 5.
Hence, probability = 5/625 = 1/125
https://math.stackexchange.com/questions/1384661/probability-of-choosing-same-number


JohnM

[John Mytton]

https://mathflight.files.wordpress.com/2014/11/4-4-multiplication-rule-basics.pdf

Please view page 4, example "homicide case".

If that's a legitimate source then I can't argue with that, it certainly fits all the parameters.

Ironically I first wrote down 1 in 4096 because that was the amount of options and then because I'm a bit rusty I thought I'd better check and came up with many examples similar to my post above which seem to make sense?

Q. There are four friends ? Adam, Bella, Christopher and Drew. All of them are asked to choose any number in their mind. Now what is the probability that every one of them has the same number in mind? The chosen number must be in between 1 to 5 (including 1 and 5).

A1. Without loss of generality, let's say Adam picks first. The probability that the other 3 choose the exact same number as Adam is 1/5∗1/5∗1/5, which gives the result of 1/125.

Note: this answer presumes that the numbers are chosen at random.



JohnM

[Walt Cakebread]

If that's a legitimate source then I can't argue with that, it certainly fits all the parameters.

Ironically I first wrote down 1 in 4096 because that was the amount of options and then because I'm a bit rusty I thought I'd better check and came up with many examples similar to my post above which seem to make sense?

Q. There are four friends ? Adam, Bella, Christopher and Drew. All of them are asked to choose any number in their mind. Now what is the probability that every one of them has the same number in mind? The chosen number must be in between 1 to 5 (including 1 and 5).

A1. Without loss of generality, let's say Adam picks first. The probability that the other 3 choose the exact same number as Adam is 1/5∗1/5∗1/5, which gives the result of 1/125.

Note: this answer presumes that the numbers are chosen at random.

JohnM

because I'm a bit rusty 

 You sure are!.....  You should be this candid more often.