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[Lysithea]

I think the probability is 1/2.

This is an English linguistic problem rather than a mathematical one.

The answer would of course be different if we were asked to select a child at random where one child is a girl and the other child's gender is unknown.

[Tresbien]

I agree with Lysithea. The clue/question reads: "A girl robot and boy robot fall in love and get married. They have two kid robots (or what ever are called) one of them is a girl robot. Given the probability of each gender is 1/2. What is the probability that the other kid is also a girl robot." It's more like a riddle with the answer contained therein than a mathematical probability question.

[PostLarval]

[Lysithea]

I maintain that this is an English language problem.

Scenario 1:
You have met one of the robot children. She is a girl.
You have no idea about the gender of the second child.
The probability is 1/2.

Scenario 2:
A friend of yours has met both children. Your friend mentions a girl, but does not mention the other child.
The probability is 1/3.

These scenarios are different because your friend had two chances of meeting a girl in scenario 2. Whereas you only had one chance of meeting a girl in scenario 1.

To me, the words in the problem could be interpreted either way.

[danteIL]

I have to agree with Lysithea -- I think that you are overthinking this. Each birth is an independent event. Therefore, each birth has a 1/2 chance of being a girl. Nothing more complicated than that.

[PostLarval]

[Lysithea]

[Abraxas]

See, they expected a split!
Especially since the passcode is equally ambiguous.

I am with PL on this one. Because probability theory is all about confusing descriptions. It is very much a language problem.
For me, the difference between those two sentences is key:

"What is the probability that the other kid is also a girl robot."
"What is the probability that the other kid is a girl robot."

First one: 1/3
Second one: 1/2



And yeah, I realise you could read this different. That's why I hate prob theory.

As for IG logic, why this should be linguistic and not mathematical, you say, because Ludd did it? Well, I bet he didn't. I bet Johnny aka Lugnut did it. And somehow sabotaged it. Maybe he deliberately kept it ambiguous, for the 36 to be split up or at least have in-fighting. And yes, that means either side could be right or wrong. I should think these arguments through next time...
Ok, I didn't pay attention in class...but someone else must have come up with this.

[PostLarval]

So to sum up what we know so far:

Lugnut (now inhabiting DICS network guy, Johnny) intercepted six documents that Ludd was trying to send out to his disciples. He forwarded these documents to the people who discovered he is still alive, and who support his efforts, with the hope that they can make sense of them.

Since it wasn't posted before, here is Johnny's message:

[Lysithea]

Nice summary, PostLarval. You should send it to Johnny.

[danteIL]

[PostLarval]

[danteIL]

[PostLarval]

[Pixiestix]

Got my reply from PNL {and since not everyone has joined the 36 & the mailing list for said group, I'll post mine now}

I decided to RP a bit for PNL since i'm being myself for 011ie & co.

WHAT I WROTE: