Random Thoughts IV: the Abyss Gazes Back

[MaryKB]

Well after about a month, I've decided I really don't like my new hair style. I'm going to need about six months to a year for it to grow back to how it was *sigh*

 

[rah]

This reply is intended to make you feel better by showing it could be worse. I'm retired. Feeding time on the weekdays is determined by when my gf gets up for work. I could sleep in, but she's up, the dogs are up, so I am up to get their breakfast. On the weekends she sleeps in, but I am still up to get their breakfast.

Thank you.

 

[Synobun]

Well after about a month, I've decided I really don't like my new hair style. I'm going to need about six months to a year for it to grow back to how it was *sigh*

Peppermint oil would possibly help it grow faster.

 

[The_J]

Get an even shorter haircut? Doesn't need to grow back to look good.

 

[Timsup2nothin]

Well after about a month, I've decided I really don't like my new hair style. I'm going to need about six months to a year for it to grow back to how it was *sigh*

Just think of all the different styles you'll be able to try out as it passes through the intermediate lengths! Fun times!

 

[Takhisis]

May I remind you lot that Mary is supposed to be getting married and there'll be pictures and people recording stuff with their 20¹⁴ megapixel 'phone cameras and children pointing and it can be so embarrassing to have your hair at any rating below 11? i mean, she carries a hairbrush everywhere because hair is that important.

25-30 years ago, certainly.

Erm, no, the point of Asterix is to reread it over and over because it's that good.

 

[Ryika]

The Monty Hall Problem...

Suppose you're on a game show, and you're given the choice of three doors: Behind one door is a car; behind the others, goats. You pick a door, say No. 1, and the host, who knows what's behind the doors, opens another door, say No. 3, which has a goat. He then says to you, "Do you want to pick door No. 2?" Is it to your advantage to switch your choice?

-> Vos Savant's response was that the contestant should switch to the other door. Under the standard assumptions, contestants who switch have a 2/3 chance of winning the car, while contestants who stick to their initial choice have only a 1/3 chance.

...is the most disgusting paradox I think I have ever come across. I understand why it works the way it does, I understand intellectually why the assumptions that feel intuitive are wrong and why the solutions that are offered are sensible and prove the paradoxical solution to be correct, and yet my brain keeps yelling "But it should not work that way, why does it work that way?!".

 

[hobbsyoyo]

My dogs love sleeping in...which they define as going back to sleep after having their breakfast. Breakfast, by imperial canine edict, shall be served at the designated time plus or minus fifteen minutes lest all hell break loose. Obviously sleeping in is not on my list of allowed activities.

This guy dogs

 

[Takhisis]

The Monty Hall Problem...

Suppose you're on a game show, and you're given the choice of three doors: Behind one door is a car; behind the others, goats. You pick a door, say No. 1, and the host, who knows what's behind the doors, opens another door, say No. 3, which has a goat. He then says to you, "Do you want to pick door No. 2?" Is it to your advantage to switch your choice?

-> Vos Savant's response was that the contestant should switch to the other door. Under the standard assumptions, contestants who switch have a 2/3 chance of winning the car, while contestants who stick to their initial choice have only a 1/3 chance.

...is the most disgusting paradox I think I have ever come across. I understand why it works the way it does, I understand intellectually why the assumptions that feel intuitive are wrong and why the solutions that are offered are sensible and prove the paradoxical solution to be correct, and yet my brain keeps yelling "But it should not work that way, why does it work that way?!".

I'd say ‘not quite’ because not switching is also a choice and you're still 50% likely to be right.

 

[MaryKB]

The Monty Hall Problem...



...is the most disgusting paradox I think I have ever come across. I understand why it works the way it does, I understand intellectually why the assumptions that feel intuitive are wrong and why the solutions that are offered are sensible and prove the paradoxical solution to be correct, and yet my brain keeps yelling "But it should not work that way, why does it work that way?!".

I feel just like you with the birthday paradox, you know that one that basically says if you have something like around 23 people, you're practically guaranteed to have at least two people with the same birthday? I think it feels just so wrong to me, but I've tested it with random number generators even and it's true.

 

[GoodSarmatian]

I don't get the Monty Hall stuff.
Statistically it makes sense, but it still looks like magical thinking. Like my choice has an impact on future probabilities.
A child is playing dice and thinks I rolled "1" twice, so the next time it has to be six.
Nope, that's not how probability works.

 

[cardgame]

I had to read through the Monty Hall scenario about a half dozen times before it still didn't make sense.

Then I went to reddit. Some kind chap immediately explained it in an immensely sensible and obvious fashion, and it is as follows: switch the number of potential doors from 3 to, say, 100. Now the odds become much more apparent and the logic still applies when you shrink the total back down to 3.

At least, it did to me. And now I'd better leave this thread lest I lose my mind again.

 

[Takhisis]

What I'm pointing out about it is that
a) I pick one at random from among three → I have 1-in-3 of getting it right
b) one of the wrong choices is taken off the table → it's now 1-in-2
c) I am still making a choice (to move or not to move) from among 2 so my odds are still 1-in-2; in effect, I am choosing from among 2 with no new information about the two options themselves.

 

[cardgame]

ah, but you discount the action of opening that door. He couldn't very well open your door, could he? So he has two doors to open, out of three total; by choosing one that is known false, it improves the odds that the last remaining door is actually good.

 

[Timsup2nothin]

ah, but you discount the action of opening that door. He couldn't very well open your door, could he? So he has two doors to open, out of three total; by choosing one that is known false, it improves the odds that the last remaining door is actually good.

But you discount that your odds are always going to be fifty fifty. When you pick a door, no matter what you pick, they are going to open a bad door. You can't stop them, since there are two bad doors. So at the end of the day there are four outcomes possible. You pick a bad door and stick, pick a bad door and switch, pick the good door and stick, or pick the good door and switch. In two of the four outcomes you wind up with the good door, and in the other two you do not.

 

[cardgame]

I was addressing the "no new information" bit. It turns out the wiki says the same thing:

the host's deliberate action adds value to the door he did not choose to eliminate, but not to the one chosen by the contestant originally.

this image is actually really helpful. There are only three doors, which means there are three ways to set up the game before it is played. Your chance of choosing a goat door out of three doors is 2/3. When the host opens a goat door, there is one goat and one car. Now, the chance of you initially guessing a car is 1/3. That is why staying with one "50%" option is actually not a true 50-50. Staying with your first door to win the car is staying with your 33% guess. That is why it makes sense to switch doors.

There, I've explained it as best I possibly can. No further questions.

https://en.wikipedia.org/wiki/Monty...nty_Hall_Problem_-_Standard_probabilities.svg

 

[Gori the Grey]

As phrased in Ryika's post ("is it to your advantage") the answer depends on whether, in the circumstances you are making the choice, a goat or a car is a more valuable thing to have.

 

[Timsup2nothin]

I was addressing the "no new information" bit. It turns out the wiki says the same thing:

this image is actually really helpful. There are only three doors, which means there are three ways to set up the game before it is played. Your chance of choosing a goat door out of three doors is 2/3. When the host opens a goat door, there is one goat and one car. Now, the chance of you initially guessing a car is 1/3. That is why staying with one "50%" option is actually not a true 50-50. Staying with your first door to win the car is staying with your 33% guess. That is why it makes sense to switch doors.

There, I've explained it as best I possibly can. No further questions.

https://en.wikipedia.org/wiki/Monty...nty_Hall_Problem_-_Standard_probabilities.svg

The explaining is being done in a way to support formation of the paradox. Proper analysis is done with elimination of paradox as an objective. That's why describing the four possible outcomes is key.

 

[cardgame]

Four possible outcomes is being done in a way to destroy the true nature of the problem. It doesn't even properly represent it. Proper analysis is done with mathematics.

 

[Takhisis]

You have a lot to learn, young grasshopper.

You are taking a random thought by Ryika seriously, cardgame-san.