Comment author: ScottL 23 August 2015 11:09:38PM *  0 points [-]

It's not a trick question. It's pretty much the same as the example used in the literature and then I have a few other examples that are straight from the literature. The literature on mental models is mainly on deductive reasoning. That is why the question is in the format it is.I have rephrased it to try to make it more clear that it is not about which algorithm is correct.

Note that the robot is a black box. That is, you don't know anything about how it works, for example the algorithm it uses. You do, however, have two statements about the what the possibilities of what the dealt hand could be. These two statements are from two different designers of the robot. The problem is that you know that one of the designers lied to you and the other designer told the truth. This means that you know that only one of the following statements about the dealt hand is true.

Can you please let me know if you think this helps. Also, did you have the same problem with the second problem.

The thing is that the problem requires a particular reading because a different reading makes it a totally different problem. Under your reading the question really is:

The dealt hand will contain cards from only one of the following sets of cards:

  • K, A, K and A
  • Q, A, Q and A

Obviously, that's a totally different problem. If you have any suggestions on how to improve the question, let me know.

Comment author: mavant 24 August 2015 01:22:24AM 2 points [-]

The fact that it's the same phrasing used in the literature is really concerning, because it means the interpretation the literature gives is wrong: Many subjects may in fact be generating a mental model (based on deductive reasoning, no less!) which is entirely compatible with the problem-as-stated and yet which produces a different answer than the one the researchers expected.

One could certainly write '(Ace is present OR King is present) XOR (Queen is present OR Ace is present)' which trivially reduces to '(King is present OR Queen is present) AND (Ace is not present)', but that gives the game away a bit - as perhaps it should! The fact that phrasing the knowledge formally rather than in ad-hoc English makes the correct answer so much more obvious is a strong indicator that this is a deficiency in the original researchers' grasp of idiomatic English, not in their research subjects' grasp of logic.

It's difficult for me to look at the problem with fresh eyes, so I can't be entirely certain whether the added 'black box' note helps. It doesn't look helpful.

What would be really useful would be a physical situation in which the propositional-logic reading of the statements is the only correct interpretation. There is luckily a common silly-logic-puzzle trope which evokes this:

The dealer-robot has two heads, one of which always lies and one of which always tells the truth. You don't know which is which. After dealing the hand, but before showing it to you, the robot dealer takes a peek.

One of the robot's heads has told you that the dealt hand contains either a king or an ace (or both).

The robot's other head has told you that the dealt hand contains either a queen or an ace (or both).

Comment author: mavant 23 August 2015 07:46:14PM 0 points [-]

Third obvious possibility: B maximises u~Σpivi, subject to the constraints E(Σpivi|B) ≥ E(Σpivi|A) and E(u|B) ≥ E(u|A). where ~ is some simple combining operation like addition or multiplication, or "the product of A and B divided by the sum of A and B".

I think these possibilities all share the problem that the constraint makes it essentially impossible to choose any action other than what A would have chosen. If A chose the action that maximized u, then B cannot choose any other action while satisfying the constraint E(u|B) ≥ E(u|A) unless there were multiple actions that had the exact same payoff (which seems unlikely if payoff values are distributed over the reals, rather than over a finite set). And the first possibility (to maximize u while respecting E(Σpivi|B) ≥ E(Σpivi|A) ) just results in choosing the exact same action as A would have chosen, even if there's another action that has an identical E(u) AND higher E(Σpivi).

Comment author: mavant 23 August 2015 06:51:41PM *  0 points [-]

The Ace is in both statements and both statements cannot be true as per the requirement.

No.

deal :: IO CardHand

deal = do

x <- randomBoolean

if x

then generateHandsContainingEitherOrBothOf (King, Ace)

else generateHandsContainingEitherOrBothOf (Queen, Ace)

Asking a trick question and then insisting on a particular reading does not constitute evidence of a logical fallacy being committed by the answerer.

Comment author: SoundLogic 06 August 2015 12:30:23AM 1 point [-]

Step one involves figuring out the fundamental laws of physics. Step two is input a complete description of your hardware. Step three is to construct a proof. I'm not sure how to order these in terms of difficulty.

Comment author: mavant 23 August 2015 06:39:25PM 0 points [-]

1-3-2 in descending order of difficulty

Comment author: itaibn0 12 November 2013 02:19:43PM 1 point [-]

...And that way you turn the problem of making an AI that won't kill you into one of making a society of AIs that won't kill you.

Comment author: mavant 12 November 2013 02:25:10PM -2 points [-]

If Despotism failed only for want of a capable benevolent despot, what chance has Democracy, which requires a whole population of capable voters?

Comment author: Vladimir_Nesov 28 December 2011 07:40:43AM *  20 points [-]

This is an incorrect description of 5-and-10. The description given is of a different problem (one of whose aspects is addressed in the recent cousin_it's writeup, the problem is resolved in that setting by Lemma 2).

5-and-10 problem is concerned with the following (incorrect) line of reasoning by a hypothetical agent:

"I have to decide between $5 and $10. Suppose I decide to choose $5. I know that I'm a money-optimizer, so if I do this, $5 must be more money than $10, so this alternative is better. Therefore, I should choose $5."

Comment author: mavant 12 November 2013 02:11:23PM 0 points [-]

I don't really understand how this could occur in a TDT-agent. The agent's algorithm is causally dependent on '(max $5 $10), but considering the counterfactual severs that dependence. Observing a money-optimizer (let's call it B) choosing $5 over $10 would presumably cause the agent (call it A) to update its model of B to no longer depend on '(max $5 $10). Am I missing something here?

Comment author: mavant 27 July 2013 06:57:54PM 3 points [-]

Don't know if this has been suggested before, but:

Possibility: Harry's "Father's rock" is the Resurrection Stone. Giving this one low probability, since it has thus far demonstrated no other magical properties, and just seems like a way to get Harry to grind his Transfiguration and mana stats.

Possibility: Harry's "Father's rock" is the Philosopher's Stone. Giving this one even lower probability.

Possibility: The Philosopher's Stone is actually the Resurrection stone, or a similar magical construct. Middling probability; Dumbledore refers to Flamel insisting "the Stone" be kept at Hogwarts, but never mentions the Philosopher's Stone; it seems quite plausible that all of the "Philosopher's Stone" rumors are in fact obfuscations about the true nature of the object, and that Flamel's wealth has more to do with his alchemical talents and his having had six centuries to accumulate capital than an actual ability to transmute base metals into gold.

Harry dismisses the possibility of the Philosopher's Stone far too readily, especially considering he already knows that magic, at least to some degree, works the way you (or the creator of a spell) believe(s) it will work, AND knows that fruit which seems low-hanging to him is obviously not so to the rest of the magical world. This smells a little bit idiot-ball-ish to me, even if he is correct.

Comment author: gjm 26 July 2013 07:35:17PM 6 points [-]

If so, then:

  • Presumably what's happening is some ritual involving the Deathly Hallows, carried out by Harry or Voldemort or both
  • Most likely with the goal of defeating Death (somehow)
  • So I guess the litres of blood are a requirement of the ritual (note: in view of earlier stuff about how modest the things sacrificed in rituals are, it had better be something as grand as defeating Death)
  • Harry doesn't seem like the type to spill other people's blood even for such a goal (though, I dunno, he might) and Voldemort may quite possibly wish to spill Harry's
  • So maybe it's Harry's blood, and he's (directly or, or letting Voldemort do it) sacrificing his own life to put a permanent end to death for everyone else
  • Which would make a certain amount of dramatic sense
  • In which case, probably the word being screamed is "No!" or "Harry!" or something of the kind
  • Though maybe it ends up with him getting resurrected too; see, e.g., canon Harry Potter, Narnia, Jesus -- the first two being deliberately derived from the latter; not so congenial an idea to Eliezer as to Rowling (who is a Christian), but note Eliezer's "Ta-da" remark when Leah mentioned "Christus Victor" and divide-by-zero errors
  • So maybe e.g. Harry needs to be killed while invisible to Death because of the Cloak of Invisibility; perhaps that sends his soul-or-similar-thing to wherever wizards' souls go, but without him actually being properly dead, and enables him to fix things up there (a very "Christus Victor" idea; maybe too much so)
  • None of this seems to connect with the prophecy about "the one with power to vanquish the Dark Lord", but maybe as others have speculated the Dark Lord in question is Death or something

All, of course, pure wild ass-speculation.

Comment author: mavant 27 July 2013 06:27:51PM 0 points [-]

Can't be Harry's blood; at age eleven he's certainly got less than 3 litres (if he weighs ~80 pounds), possibly little more than two (can't recall if HJPEV is as skinny as Canon!HP). If you cut off a limb, he might have as much one litre "spill" out, but the rest would just sort of... dribble in spurts.

Comment author: arborealhominid 26 July 2013 01:36:26AM *  0 points [-]

If you put the cloak over someone who is dying, they would stay alive, at least until the Cloak is removed and death can find them again.

I'm surprised Harry didn't try this for Hermione, then. Maybe he wouldn't have expected it to work, but it's still an easy hypothesis to test.

It was amazing how many different ways there were to kill your best friend by being stupid.

Comment author: mavant 27 July 2013 06:08:53PM 4 points [-]

It's a shame you retracted this, because I wanted to +1 it.

Comment author: TimS 26 July 2013 01:39:14AM 0 points [-]

Or the ritual from the beginning of Gaiman's Sandman?

Comment author: mavant 27 July 2013 06:06:22PM 0 points [-]

That ritual required quite a number more components... But then, it didn't WORK, so perhaps Burgess and his order meant to perform the one Quirrell meant.

This is my headcanon, now.

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