JeffJor

7 ms·

1. 1.▲
   by JeffJor 1y ago

   Mr. Bertrand has (exactly - this needs to be included) two children (not twins, which is not quite the same as different ages). A gender, and a day of the week, that apply to at least one of his children have been written inside a sealed en
2. 2.▲
   by JeffJor 1y ago

   And when you don't know, you have to assume it is 50:50. Otherwise you get different answers for different-but-equivalent information.
3. 3.▲
   by JeffJor 1y ago

   > The reasons why the original problem is so confusing is the same reason why the Monty Hall is so confusing: people have different understandings of the question, and don't realize it in discussions. Almost everybody understands th
4. 4.▲
   by JeffJor 1y ago

   I am not making an assumption about the data-generating process in any of these questions. The only “assumptions” I make are that the information is true (so yes, the envelope in Q3 matches the family), that the information (whether or not
5. 5.▲
   by JeffJor 1y ago

   Bertrand's Box Paradox, which I wrote about in my own comment, applies to it. The upshot is that probability is not based on which prize placements _could_ lead the current game state, it is the set of all possible game states. Lets as
6. 6.▲
   by JeffJor 1y ago

   Q1: "A family has two children. You're told that at least one of them is a girl. What's the probability both are girls?" Q2: "A family has two children. You're told that at least one of them is a boy. What&#x27
7. 7.▲
   by JeffJor 3y ago

   The problem is ambiguous, due to under specification. That means that neither #1 nor #2 is "actually equivalent" to "at least one child is a boy," and more information is needed to construct a probability space. #1 is &q