Here’s the quiz:
(It is my belief that this quiz is not even slightly, not in the least tricky at all. But am I missing something?)
I teach exactly this–not this quiz, but this concept–to high school juniors, and even in an AP class it is amazing how many of them struggle with it. Most of them would get 70-80% of that quiz correct, and more than a few would get all of them, but there would be a surprisingly large chunk (maybe 25%?) who wouldn’t really get it, even after direct instruction and a list of indicator words. Add a few more premises to each conclusion, and the results get even more dismal.
That said, this is teachable. They get better at it over time and with enough practice. Unfortunately, most school systems give high school kids 4 years of literature and very little practice in argumentation. I use a college logic textbook in my class.
I didn’t really answer the question. Why is it so difficult? I think it has to do with a lack of practice in analysis. Everything is taught so holistically these days that kids don’t think in terms of taking something apart and looking at the function of each piece.
…do I dare draw the ire of this board and ask if number 3 was the right one? 
I can see arguments on a few of them. For example,
Is Maria (apparently, we conclude) going to become a doctor because of her interest in medical matters, or is she interested (apparently, we conclude) because of her intent to become a doctor?
You’re supposed to pick a sentence from each pair. One sentence in each pair is a conclusion, the other a premise giving a reason (good or bad) to believe that conclusion.
So you’re saying the logic of it might be “Here’s how we can know she reads a lot of medical thrillers: We know independently that she’s probably going to become a doctor”?
Aw… I was hoping maybe it would get better with longer passages, thinking maybe when you give them these two-sentencers abstracted from any other text, they get a little lost at sea. Looks like my hope (and really it was just a desperate hope, not something I had any serious expectation of turning out true) is dashed.
Well, I’m teaching students who for the most part may not have done so well in High School, or may not even have finished it, or who finished it long, long ago and who have done nothing academic since then. I have to admit that though I’ve learned (I thought) to be prepared for anything from students, and to always see it as an opportunity to help, things here where I teach now have been seriously eye-opening.
Ohhhhh, beg your pardon. So we’re not actually looking for the fallaciousness of the claim, but rather, which is the premise and which –
Oh, ok. Gotcha!
Try teaching them to notice and circle indicator words–because, therefore, as a result, so, etc. We “natural readers” (i.e., future teachers) don’t even notice we use these, and don’t realize that weak readers tend to tune them out as meaningless noise. I was teaching someone to drive once and it took me like ten sessions to tell them to pay attention to other people’s taillights–experienced drivers do so so automatically that we don’t realize it has to be taught. This is the same kind of thing.
I really, really like the examples in Hurley’s Introduction to Logic to teach premises and conclusions. Lots of good examples taken from all kinds of “real” arguments. He also has a nice section on argument mapping (where several premises support one conclusion, which itself supports another conclusion, that type of thing) and really good logical fallacies problems as well.
I do this, though I also tell them that keywords are rules of thumb only and can be deceptive. You’ll note at least one of the examples in the quiz in the OP has a misleading keyword in it.
But I dunno, maybe start 'em off with explicitly keyword oriented teaching, with no tricks, just to get them into the habit of noticing them? But what I’m afraid of here is neglecting to teach them how to understand the passage and instead teaching them how to tell me which sentence has the word “so” in it…
But I guess maybe it could work–first make sure they’re noticing them, then once they’ve mastered this, then throw in some tricks so their attention is drawn from a focus on pure keyword-spotting…
That’ll mean next time I teach this course, I get to spend two to three entire weeks on just getting them to reliably spot conclusions in two-sentence inferences. Okay. If I have to do that, that’s what I’ll do.
Suppose Maria has told you she intends to be a doctor. You see her reading medical thrillers once. Later, you ask if she’s interested in doing XYZ, and she says no, holding up a new, different medical thriller. You think to yourself, I guess she spends most of her time reading that stuff, because I know she wants to be a doctor.
I know the test is looking for the other answer, but there’s a kind of thinking that wants to cast these as real situations.
I got confused because it says*…pick out the sentence which…* and there are a lot of sentence fragments. I wondered if that was supposed to be the tricky part.
i laughed. but not at you. but kind of at you.
Classic overanalysis. You should be a Literature Teacher/Professor, thats all they do.
There are no sentence fragments in the quiz.
Yeah, I wasn’t saying your reading couldn’t possibly make sense, I was just making sure I’d understood what you meant.
I can imagine stories like this for any (non-keyworded) pair of sentences you give me. But in any pair good for a quiz like this, one of the two possible readings should pop out as involving the least number of unstated situational presuppositions–as being the most plausible, in other words. I do recognize, though, that this “popping out” is an acquired skill, not something that just comes natural with reading. I think part of what I’m teaching does involve, for some students, in part, acquisition of just this skill.
See, that’s where I messed up also. I was reading too much into it. 
I’m reading down the list saying “well THAT’S not true, (and thinking, well the quiz didn’t say it had to be a true conclusion), so am I supposed to conclude (snort) that some of the sentences are incorrect and don’t contain a conclusion? Or am I supposed to ARRRGGGGHHH”.
That’s exactly what I thought until I realized what the quiz was actually testing (which I realized after reading down the thread some). Number 3 is the only one where we have enough information for the conclusion to actually follow.
I’d bet the average SDMBer would do fairly poorly on this test. I’ve seen lots of people here who don’t know a fact from an opinion, which is a simpler concept than that discussed in this thread.
ETA: To answer the OP, I didn’t find it tricky at all (once I realized what the question was).
The only thing that was confusing was the wording. Only after I started reading all the examples did I realize what it was asking for.
The inference is the conclusion. That’s what threw me off. The other sentence is what we already know.
Or maybe I’m just dumb?
I also at first thought we should be only picking one number, but that didn’t make any sense because they were all about different things!
“My dog has three legs” isn’t a sentence fragment, but with the addition of that preposition it’s no longer a complete sentence. It simply looks like it’s been split off from the sentence that preceded it, rather than being complete on its own.