In an experiment

Answer choices

1. A

   Unsupported Relationship19% picked this

   If the subjects had always guessed that the next image would appear at the top, they would not have been basing their guesses on

   Let's stop at the trigger and ask ourselves if we know anything ... were there any people that always guessed the next image would appear at the top? We don't really know. We know that most of them didn't guess that, since they were wrong most of the time. And the final sentence is giving us a counterfactual about what would have been true if they had all always guessed "next image will be on top". So given that we don't know anything about this trigger, it's hard to say we can derive a must be true of what would follow. If we assume that nobody was constantly guessing "next image on top", then this answer is just talking about a counterfactual. It's saying, "Yeah, nobody guessed X, but if they had guessed X, it wouldn't have been based on any pattern they believed they saw." How would we prove that counterfactual? How can we say in a hypothetical situation what someone would / wouldn't have believed they saw in the sequence? The contrapositive of this conditional rule is saying: if they were basing their they would not have guesses on a pattern ? always guessed next they believed they saw image on top We know for a fact that all of the subjects were guessing based on a pattern they believed they saw. So according to this answer choice, none of them would have guessed "next image will appear on top". That's too strong. We know most of them weren't guessing "next image will appear on top" because most of the time they were wrong, but it's still possible that some of the subjects guessed "next image will appear on top". It's possible that some subjects guessed perfectly. The low accuracy of all the other subjects could lower the group's accuracy to where it's still true to say "the subjects guessed correctly less than half of the time". (as a desperation move, you might avoid guessing this tempting answer because Must Be True questions often put a very tempting but wrong answer non-coincidentally into the slot for choice (A). Given that this answer was conditional strength and in a famously trappy spot, we might convince ourselves we're safer choosing something farther down in the answer choices that also makes sense)

   19%
2. B

   Too Broad / Strong9% picked this

   Basing one’s guesses about what will happen next on the basis of patterns one believes one sees is less likely to lead to correct

   This answer is too strong because it's presented as a truism that goes beyond this experiment. We would only be able to comment on what sort of guessing would have had what sort of accuracy for this experiment. We can't extrapolate a rule that's applicable to other situations.

   9%
3. C

   Too Strong: no pattern6% picked this

   There was no predictable pattern that one could reasonably believe occurred in the series of images

   It's possible there was a predictable pattern someone could have reasonably believed occurred. Maybe it looked like it was doing "3 tops, 1 bottom, 3 tops, 1 bottom". Even if it didn't end up doing that exact pattern, it might have been close enough to that for us to say there was a predictable pattern that one could reasonably believe occurred. The fact that these people thought they saw patterns, but were largely wrong, doesn't make those patterns unreasonable ones to believe you saw.

   6%
4. D

   Correct57% picked this

   Some of the subjects sometimes guessed that the next image would appear at the bottom of the computer

   Why this is right

   This is weird, but at least appealing because of how safe/soft the language is. Can we prove that at least once in this experiment, some guessed "next image will be at the bottom" and ended up being wrong? It sure sounds very very plausible. After all, we know that they were mostly wrong and that the images were mostly occurring at the top of the screen, so you'd assume that there was at least one time where one of the wrong guesses was "next image will be bottom." In order for this weak statement to be false, we'd have to show that it's possible that people were never wrong when they guessed "bottom". All of their wrong answers came from guessing "top" and being wrong. We can prove this statement using Most + Most quantifier logic. Whenever we have these two ideas: Most A's are B Most A's are C we can infer Some B are C We know that Most images appeared at the top Most images were incorrectly guessed So we can infer that "some incorrect guesses were images that appeared at the top". We know that most images appeared at the top because the first sentence says that images usually (i.e. more than 50% of the time) were on top. We know that most guesses were incorrect, because "they guessed correctly less than half of the time", so they guessed incorrectly more than half of the time. Thus, (and nauseatingly), we can derive that at least one of those wrong guesses had to occur when the image appeared at the top of the screen. In order to have a wrong guess about an image that appears at the top of the screen, it must be that the person guessed bottom of the screen.

   Skill tested: Must be True · how this choice captures the argument's function is the move to repeat next time.

   57%
5. E

   Out of Scope10% picked this

   The most rational strategy for guessing correctly where the next image would appear would have been simply to always guess that the

   Out of Scope: rational Too Strong: most rational Just because the subjects turned out to be wrong most of the time doesn't mean they were necessarily behaving irrationally. They thought they perceived a pattern. Making a guess based on a perceived pattern is pretty rational. We call that inductive reasoning. We certainly don't have any ammunition in this paragraph for deciding what the most rational strategy was here.

   10%