#19 - Studies have shown that pedestrians are struck by cars

[Brook Miscoski]

jayzbrisk,

Two things:

(1) The LSAT instructs you not to make assumptions that are by commonsense standards implausible. I believe this means that you have to resolve the meaning of answer choices along commonsense lines.

(2) Keeping (1) in mind, if a plausible interpretation exists that strengthens, and a plausible interpretation exists that weakens, that is a problem for the answer choice unless you're doing a very specific question like "the answer to which of the following questions would be most helpful in evaluating the reasoning above."

The stimulus is simple. It's causal. It proposes that carelessness causes the accidents. Another cause would weaken the stimulus. Answer choice (A) indicates that the accidents are happening in a high traffic area, an alternative cause by any commonsense standard.

[ashnicng]

The scenario outlined in Answer Choice (A) provides an alternative. What if the reason why there are more collisions in crosswalks is simply because there are far more pedestrians who cross in crosswalks than pedestrians who jaywalk. There need not be an increased likelihood of a collision in a crosswalk. Instead, the sheer number of pedestrians in crosswalks means that more collisions are bound to happen, even if such collisions occur a lower percentage of the time than they do when pedestrians jaywalk.

Hello! I understand that A is the best answer, but I'm a little thrown off by the added qualification of "in high-traffic areas" to "pedestrians." I would've felt even more confident in this answer without the added qualification because the stimulus refers to "pedestrians" generally. So, if the overall majority of pedestrians, in general, cross streets in crosswalks, it provides a clear alternate explanation for the conclusion. I could overlook this uncertain feeling, but I'd like to know if this uncertainty is justified. Thank you!

[KelseyWoods]

Hi ashnicng!

I understand your uncertainty with the "high-traffic areas" qualification--you've probably noticed that a lot of incorrect/correct answers on the LSAT hinge on one word or phrase so it's good to be reading each word carefully! In this case, the phrase"high-traffic areas" shouldn't bother us too much. It makes sense that people crossing streets in high traffic areas would be more likely to get hit than people crossing streets in low traffic areas. Adam actually already gave a great explanation of this to an earlier poster who had a similar issue with answer choice (A) so I'm just going to quote him below:

Hey there jayzbrisk, that was a lot of analysis, but let me get to something you said at the very end:

The only way I see answer A as a contender is to assume that it is more likely to get hit in a high traffic area

Is that really too much of an outside assumption? If I asked you to cross a street with high traffic, like for example a busy downtown street in a city during rush hour, wouldn't you expect a greater sense of danger than if you were to cross, say, a one-lane farm road in the middle of nowhere?

Answer A does require the assumption that the danger of being hit by a car is greater when there are more cars than when there are relatively few, but that is not a big outside assumption. Rather, that sounds a lot more like common sense, the kind of outside info that you are expected to bring to bear on the LSAT, like knowing that animals require food and water and air to survive, or that if the sun is shining then it is probably daytime.

While we could certainly come up with numbers that suggest that answer A does not disprove the conclusion here, that is not the standard to apply to a weaken question. Instead, all we need is some element of doubt - in this case, the possibility that there is some other cause for the results in the stimulus. Answer A suggests a possible alternate cause for the numeric info given, and that is enough for it to weaken the argument, even if it is not completely disproven. If the cause for the disparity could be just that more people cross in crosswalks in areas where the danger is at its highest, then we cannot be so sure that "overconfident/not paying attention" is the cause.

Remember, to weaken, don't try to disprove! Just look for the answer that introduces an element of doubt.

Hope this helps!

Best,
Kelsey

[VamosRafa19]

I think you're on to something there, Rita, and if we didn't have the better answer in A, C might be a contender. Traffic signals malfunctioning at a higher than expected rate might be the alternate cause for collisions in crosswalks instead of pedestrians not paying attention - but why does that happen more often in crosswalks than out of them? Answer C really doesn't help explain that discrepancy. Why would malfunctioning signals lead to more collisions than in places where there are no signals at all, unless it's due to the differing levels of care exercised by the pedestrians? We end up pretty much right back where we started, not having strengthened anything.

This one is all about numbers. Let's say 10 people are hit in the crosswalk, and 5 are hit outside the crosswalk. Out of how many? Answer A suggests that the first group is much larger than the second - let's say those 10 are out of 10,000, and those 5 are out of 10. The larger number of folks being hit in the crosswalk may simply be due to the much larger opportunity for that to happen! No need to blame careless pedestrians putting too much trust in the signals, it's just something that happens sometimes.

I'm still not sure why C is wrong. Based on the explanation above, particularly "but why does that happen more often in crosswalks than out of them? Answer C really doesn't help explain that discrepancy. " I guess I would have thought because when crossing outside of crosswalks there's not usually signals to follow so they don't malfunction?

I understand the numerical analysis above, but I read "pedestrians are struck by cars more often in xwalks than they are struck when crossing outside of xwalks" to mean that the rate, or incidence was higher not necessarily that the raw number was higher. Is there a subtlety in the language I'm missing?

[Adam Tyson]

"More often" is a numbers idea, not a rate idea, so that may be where you are having trouble. The problem with the argument is that it compares raw numbers rather than rates, but if you want to know what is safer or more dangerous, you want to know the rate. What are the odds of getting hit? That's the real question.

[rragepack]

Dear Powerscore,

I was wondering if we should treat this stimulus as a set of facts or an argument. If we should treat it as an argument what is the conclusion and what are the premises?

Thank you.

Best,
rragepack

[Adam Tyson]

This is a relatively rare case of "neither," rrage. Sort of. It's not just a fact set, because the author isn't just giving us facts, but has also offered an opinion that attempts to explain those facts. But it's not exactly an argument either, because the conclusion is not explicit but implied. Notice that the stem doesn't ask us to undermine an argument, but to undermine an explanation. So our job is to raise doubts about the explanation. Come up with some new info that raises doubts about "overly strong sense of security" being the cause of more pedestrians being struck.

If you want to think of this like an argument, it goes this way:

Premise: Pedestrians have an overly strong sense of security in crosswalks and are less likely to look both ways

Premise: More pedestrians are struck in crosswalks than elsewhere

Conclusion: That sense of security/failing to look is the cause of more pedestrians being struck in crosswalks than elsewhere

When I see "weaken the explanation" or "strengthen the hypothesis" or "undermine the theory," I tend not to focus on whether it is an argument or not. Instead, I look at the explanation or hypothesis or theory and just think about what would make that less likely to be true.

[Henry Z]

I’m still confused by the language here.

Much has been discussed about “more often”, but what does “they” in the first sentence mean? As I understand, grammatically, a personal pronoun refers back to someone previously mentioned, so I understand “they” as the very same pedestrians mentioned earlier. But if so, the same base group is more often struck in crosswalks than outside of crosswalks, seems a comparison between rates, instead of raw numbers.

If the stimulus doesn’t use a pronoun, instead it says "pedestrians are struck by cars when crossing street in crosswalks more often than pedestrians are struck when crossing outside of crosswalks”, I would not assume the twice mentioned “pedestrians” are the same group of people. But using "they" is clear-cut for me.

Do I understand "they" incorrectly here?

[Adam Tyson]

"They" refers to pedestrians in general, Henry, and the sentence as written means exactly the same as what you wrote here:

"pedestrians are struck by cars when crossing street in crosswalks more often than pedestrians are struck when crossing outside of crosswalks."

It's not necessarily the same pedestrians being hit in two different places, but just about the total number of pedestrians being hit in the two different circumstances. The number that are hit in crosswalks exceeds the number hit outside crosswalks. Not a rate, just a number, and that larger number could be explained by differences in the frequency of the two actions being compared rather than by differences in the behaviors within those two groups.