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Seven Puzzles You Think You Must Not Have Heard Correctly (2006) [pdf]

math.dartmouth.edu

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Re: Seven Puzzles You Think You Must Not Have Heard Correctly (2006) [pdf]

#171

Post by posterboy »

andrepd wrote: post #166
posterboy wrote: post #147

Earlier quoted context omitted.

Good grief. If you want to write objective, do so, and ommit personal pronouns all together, but don't employ this archaic, confusing grammatical quirk. I'd like to point out to you, ekke's comment was much better understandable and shorter. Edit: Did you even read what you linked? > One explanation given for some uses of they referring to a singular antecedent is notional agreement, when the antecedent is seen as se…

You seem to be very angry with a feature of English grammar. Using they/them/their is a perfectly reasonable, consistent and well-understood way to refer in the third person to someone of unknown gender. How would you rewrite the sentence "If the light is on when F gets to the room, they turn the light off, and they increment their counter." without using they?

I am not angry with a feature of the language. I am angry with the people abusing a bug, for lack of a better word, that makes a simple language overly complicated. I am angry, because I didn't understand the whole comment. In my opinion that is not just my fault. It was, in many ways, terribly written. I think a little meta discussion is beneficial. Seeing that it is a question of logic and we are in a logic puzzle thread, I think, you should try to answer your question yourself.

> consistent

If that was a consistent feature, or better to say regular, there would be the -s inflexion on the verb, that the singular third person requires.

> well-understood

What does that even mean? In the referred article, were, as I said, at least two counts against the particular usage in the GP.

> How would you ...

What does it matter? Are you saying there is no other way? Why don't you give it a try yourself, it's not hard. For starters, just try replacing "they" with "F".

Re: Seven Puzzles You Think You Must Not Have Heard Correctly (2006) [pdf]

#172

Post by gohrt »

Some of these are poorly worded:

* Kleptopia is ambiguous about what gets stolen, and what toplogy the boxes/padlocks must have for the solution.

* The "clever" solution to Unwanted Expansion isn't a complete proof, unless you add some complicated reasoning or use the non-clever proof, but if you do that, you don't need the "clever" proof at all.

* The Wimbledon puzzle doesn't explain the scoring rules of tennis :(

Re: Seven Puzzles You Think You Must Not Have Heard Correctly (2006) [pdf]

#173

Post by posterboy »

twhb wrote: post #148

I collect riddles like these! Here are a few of them. Numbered Hats A warden places a hat on the head of each of 100 prisoners, each with a random number from 1 to 100. There may be duplicates. Each prisoner can see everybody's hat but their own. Each prisoner then guesses their own number; if any guess correctly, they all go free. The group may not communicate in any way during the trial, but may strategize beforeha…

Numbered Hats: Are the guesses secret?

Colored Hats:

The first one makes a sacrifice and says the color of the next hat. He has a 0.5 chance. The next person thus has a chance of 1. The third has to make a sacrifice again. Naively that is an average 0.75 chance over all. An exact calculation is too complicated for my taste.

Re: Seven Puzzles You Think You Must Not Have Heard Correctly (2006) [pdf]

#174

Post by evanb »

posterboy wrote: post #147
andrepd wrote: post #137

Earlier quoted context omitted.

https://en.wikipedia.org/wiki/Singular_they

Good grief. If you want to write objective, do so, and ommit personal pronouns all together, but don't employ this archaic, confusing grammatical quirk. I'd like to point out to you, ekke's comment was much better understandable and shorter. Edit: Did you even read what you linked? > One explanation given for some uses of they referring to a singular antecedent is notional agreement, when the antecedent is seen as se…

Although you allege ekke's comment was "much better understandable", it commits the same use of they as singular.

> Others follow a simple pattern - if the light is off, and they have never turned it on yet, turn it on. If it is already on, or they have already ever turned it on, do nothing.

"They" cannot possibly be referring to the group---"they" is referring to each person individually. If it's referring to the others as a group, it's not a solution to the puzzle.

And yet, you found it understandable.

Re: Seven Puzzles You Think You Must Not Have Heard Correctly (2006) [pdf]

#175

Post by evanb »

twhb wrote: post #148

I collect riddles like these! Here are a few of them. Numbered Hats A warden places a hat on the head of each of 100 prisoners, each with a random number from 1 to 100. There may be duplicates. Each prisoner can see everybody's hat but their own. Each prisoner then guesses their own number; if any guess correctly, they all go free. The group may not communicate in any way during the trial, but may strategize beforeha…

Numbered hats: I'm not sure this is optimal.

When the prisoners are together, they assign each person a unique ID from 1 to 100.

Once the round starts, each looks around and adds up the total on everybody else's hat, mod 100. Suppose you see a total of h (mod 100). Then you should make a guess g = h - your ID (mod 100).

With 1000 repeated experiments of 1000 trials each, this saved the prisoners ~ 630±17 ~= 63±2 percent of the time.

Re: Seven Puzzles You Think You Must Not Have Heard Correctly (2006) [pdf]

#176

Post by twhb »

posterboy wrote: post #173
twhb wrote: post #148

I collect riddles like these! Here are a few of them. Numbered Hats A warden places a hat on the head of each of 100 prisoners, each with a random number from 1 to 100. There may be duplicates. Each prisoner can see everybody's hat but their own. Each prisoner then guesses their own number; if any guess correctly, they all go free. The group may not communicate in any way during the trial, but may strategize beforeha…

Numbered Hats: Are the guesses secret? Colored Hats: The first one makes a sacrifice and says the color of the next hat. He has a 0.5 chance. The next person thus has a chance of 1. The third has to make a sacrifice again. Naively that is an average 0.75 chance over all. An exact calculation is too complicated for my taste.

Numbered hats: yes, they don't hear what the others guess. Of course, they could still "know", if they'd agreed upon guesses beforehand.

Colored hats: true, but you can do better than 75%-ish.

Re: Seven Puzzles You Think You Must Not Have Heard Correctly (2006) [pdf]

#177

Post by agf »

evanb wrote: post #175
twhb wrote: post #148

I collect riddles like these! Here are a few of them. Numbered Hats A warden places a hat on the head of each of 100 prisoners, each with a random number from 1 to 100. There may be duplicates. Each prisoner can see everybody's hat but their own. Each prisoner then guesses their own number; if any guess correctly, they all go free. The group may not communicate in any way during the trial, but may strategize beforeha…

Numbered hats: I'm not sure this is optimal. When the prisoners are together, they assign each person a unique ID from 1 to 100. Once the round starts, each looks around and adds up the total on everybody else's hat, mod 100. Suppose you see a total of h (mod 100). Then you should make a guess g = h - your ID (mod 100). With 1000 repeated experiments of 1000 trials each, this saved the prisoners ~ 630±17 ~= 63±2 perc…

If each person just guesses a random number you succeed the same amount of the time. You have a 99% chance of guessing wrong. The chance of 100 people guessing wrong is 0.99 ^ 100. So the chance of at least 1 person guessing right is 1 - 0.99 ^ 100, which is 63.4%.

Re: Seven Puzzles You Think You Must Not Have Heard Correctly (2006) [pdf]

#178

Post by andrepd »

posterboy wrote: post #171
andrepd wrote: post #166

Earlier quoted context omitted.

You seem to be very angry with a feature of English grammar. Using they/them/their is a perfectly reasonable, consistent and well-understood way to refer in the third person to someone of unknown gender. How would you rewrite the sentence "If the light is on when F gets to the room, they turn the light off, and they increment their counter." without using they?

I am not angry with a feature of the language. I am angry with the people abusing a bug, for lack of a better word, that makes a simple language overly complicated. I am angry, because I didn't understand the whole comment. In my opinion that is not just my fault. It was, in many ways, terribly written. I think a little meta discussion is beneficial. Seeing that it is a question of logic and we are in a logic puzzle…

>What does it matter? Are you saying there is no other way? Why don't you give it a try yourself, it's not hard. For starters, just try replacing "they" with "F".

Lol. It does matter because you are bitching about using they when you don't even say what on earth are we supposed to say instead.

Replace they with the name? "If the light is on when Franklin gets to the room, Franklin turns the light off, and Franklin increments his or her counter." Yeah sounds perfectly natural. Pronouns are for losers.

Re: Seven Puzzles You Think You Must Not Have Heard Correctly (2006) [pdf]

#179

Post by tiglionabbit »

x1798DE wrote: post #162
tiglionabbit wrote: post #155

Earlier quoted context omitted.

If two people have blue eyes, "Somebody has blue eyes" is not new information, because everyone has already seen that someone has blue eyes.

> If two people have blue eyes, "Somebody has blue eyes" is not new information, because everyone has already seen that someone has blue eyes. The new information in that scenario is that the other guy with blue eyes knows that someone has blue eyes.

If they have seen someone with blue eyes they would already know that.

Re: Seven Puzzles You Think You Must Not Have Heard Correctly (2006) [pdf]

#180

Post by evanb »

agf wrote: post #177
evanb wrote: post #175

Earlier quoted context omitted.

Numbered hats: I'm not sure this is optimal. When the prisoners are together, they assign each person a unique ID from 1 to 100. Once the round starts, each looks around and adds up the total on everybody else's hat, mod 100. Suppose you see a total of h (mod 100). Then you should make a guess g = h - your ID (mod 100). With 1000 repeated experiments of 1000 trials each, this saved the prisoners ~ 630±17 ~= 63±2 perc…

If each person just guesses a random number you succeed the same amount of the time. You have a 99% chance of guessing wrong. The chance of 100 people guessing wrong is 0.99 ^ 100. So the chance of at least 1 person guessing right is 1 - 0.99 ^ 100, which is 63.4%.

Well then, I guess my strategy accomplishes nothing!
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