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Nearing Completion of Evaluation of RS system (not)

oobiedoobie
oobiedoobie
Oct 30, 2011
11:21am
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Quote
Originally posted by: mrmarcus12LVA
Quote
Originally posted by: FrankKneeland Nothing happens in your head when you name one of the girls... Naming one of them changes everything, it just isn't obvious unless you do the work on paper. According to the book I read, this is an example of a ubiquitous cognitive distortion we all have, caused by a heuristic the brain uses to solve such problems.
Obviously, the author is full of shit. Nothing changes anywhere when I name something... except in my head, where a cognition is created. That cognition changes nothing, except itself. There is no change to the thing that was named.

Naming a girl "Florida" doesn't create a girl named "Florida" (which "expands the sample space," according to the inane author). It is through such specious reasoning that we can construct proofs that the sex of one child depends upon the sex of A DIFFERENT CHILD.


I agree that he's usually full of shit but this time he's right. Change the example to once in a while one of the set of twins is a Martian and all Martians are girls. If you know one of the twins is a Martian you are eliminating the subset of 2 non=Martians and only focusing on the remaining subset (MB,MG).
BobOrme
BobOrme
Oct 30, 2011
1:13pm
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Quote
Originally posted by: snidely333
Quote
Originally posted by: BobOrme
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Originally posted by: FrankKneeland
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Originally posted by: snidely333

Naming the child does change the probability. It is the same as saying the first born twin is a girl. What is probability that the second twin is also a girl. That is 50%.

Saying that one of the twins is a girl, what is probability both are girls is 33%.


Well I'm at least glad somebody understood the answer and the reason for it.


I thought the question didn't involve twins, but was about two separate births. The chances of the first birth being a girl would be 50%. That would not affect the chances of the second birth also being a girl. If the pill lands on a black number on a roulette wheel, that doesn't alter the chances of it landing on a black number on the next spin.


2 spins of roulette wheel.
One spin is red. What is probability both spins are red?
First spin is red. What is probability both spins are red?

What I'm saying is, the birth of twins is a single event. That would allow for 4 different possible combinations in that single event.
snidely333
snidely333
Oct 30, 2011
1:30pm
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Quote
Originally posted by: BobOrme
Quote
Originally posted by: snidely333
Quote
Originally posted by: BobOrme
Quote
Originally posted by: FrankKneeland
Quote
Originally posted by: snidely333

Naming the child does change the probability. It is the same as saying the first born twin is a girl. What is probability that the second twin is also a girl. That is 50%.

Saying that one of the twins is a girl, what is probability both are girls is 33%.


Well I'm at least glad somebody understood the answer and the reason for it.


I thought the question didn't involve twins, but was about two separate births. The chances of the first birth being a girl would be 50%. That would not affect the chances of the second birth also being a girl. If the pill lands on a black number on a roulette wheel, that doesn't alter the chances of it landing on a black number on the next spin.


2 spins of roulette wheel.
One spin is red. What is probability both spins are red?
First spin is red. What is probability both spins are red?

What I'm saying is, the birth of twins is a single event. That would allow for 4 different possible combinations in that single event.


if you eliminate green from the roulette wheel, 2 spins allows for 4 different possible combinations. The math is the same.
marlo36
marlo36
Oct 30, 2011
3:30pm
Block User
I think I solved the Who Keeps Sheep puzzle in its entirety. Please feel free to correct me if I am wrong:

House #1-Brit, Tudor house, Guinness, long bow, horse
House #2-Viking, mud house, mead, mace, pig
House #3-Dane, grass hut, water, long sword, cow
House #4-Goth, cloth tent, ale, battle axe, sheep
House #5-Norman, brick house, wine, rapier, tiger

It took me about 45 minutes to get all this, so I sure hope I'm right.

FrankKneeland
FrankKneeland
Oct 30, 2011
3:38pm
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Quote
Originally posted by: snidely333
2 spins of roulette wheel.
One spin is red. What is probability both spins are red?
First spin is red. What is probability both spins are red?


This is the same as the Two Girls question with a twist. I like it. Assuming a zero and double zero as per American roulette--

One spin is red. What is probability both spins are red? = 31.03%
First spin is red. What is probability both spins are red? = 47.369%

~FK
mrmarcus12LVA
mrmarcus12LVA
Oct 30, 2011
3:47pm
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Quote
Originally posted by: oobiedoobie this time he's right. Change the example to once in a while one of the set of twins is a Martian and all Martians are girls.
My God, people, there were not even any twins in the problem, as stated:

Quote
Originally posted by: FrankKneeland
New puzzle: The Two Girls

Assuming the chances are 50/50 for having a boy or a girl.

What are the chances that a mother giving birth to two babies will have
two girls (we are excluding identical twins)?


All that is stated here is two children from the same mother, i.e. siblings. Similarly, there were no sheep in the problem about sheep. Anyone can prove anything by simply changing the question to include their answer. Is this 4th grade?

It doesn't matter WHICH sibling is identified by sex. The other sibling has a 50% chance of being a girl, according to the problem, as stated.

Quote
Originally posted by: FrankKneeland
One spin is red. What is probability both spins are red? = 31.03%
First spin is red. What is probability both spins are red? = 47.369%

~FK


This isn't mathematics, it's jargon masqueraded. Posit only that the second spin is red. What is probability both spins are red? So fs = r -> .47 and ss = r -> .47, but os = r -> .31 I'm predicting a Nobel prize, in mysticism.
mrmarcus12LVA
mrmarcus12LVA
Oct 30, 2011
5:01pm
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Quote
Originally posted by: FrankKneeland "Ah now I get it! The reason the answer changes is because the question changes when you ask about specific things, such as a named girl. Without a name the girls are generic, and can come in any order.
Complete gibberish. Naming something doesn't change it. Neither its order, nor its generic-ness. A coin flip called Charles is still just a coin flip.

mrmarcus12LVA
mrmarcus12LVA
Oct 31, 2011
12:05am
Block User
Posit half the cattle are male and half are female. Posit the cattle are corraled, and then two are moved into a pen.
1. What is the chance AT LEAST ONE of the cattle in the pen is female?
2. If one of the cattle in the pen is female, what is the chance the other is female?

EXTRA BONUS: Why did your answer to question 2 change when the two were moved into the pen?
snidely333
snidely333
Oct 31, 2011
12:13am
Block User
Quote
Originally posted by: mrmarcus12LVA
Posit half the cattle are male and half are female. Posit the cattle are corraled, and then two are moved into a pen.
1. What is the chance AT LEAST ONE of the cattle in the pen is female?
2. If one of the cattle in the pen is female, what is the chance the other is female?

EXTRA BONUS: Why did your answer change when the two were moved into the pen?


1. 75%
2. 33.3%

What point are you trying to make?
mrmarcus12LVA
mrmarcus12LVA
Oct 31, 2011
12:16am
Block User
HOW MANY CATTLE WERE IN THE CORRAL??????
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