This region’s swimmers generally swim during the day because they are

Question

This region’s swimmers generally swim during the day because they are too afraid of sharks to swim after dark but feel safe swimming during daylight hours. Yet all recent shark attacks on swimmers in the area have occurred during the day, indicating that, contrary to popular opinion, it is not more dangerous to swim here at night than during the day.

The reasoning in the argument is most vulnerable to criticism on the grounds that it

(A) overlooks the possibility that some sharks are primarily nocturnal hunters
(B) bases its conclusion on evidence from an unreliable source
(C) overlooks the possibility that swimmers might feel anxiety caused by not being able to see one’s surroundings in the dark
(D) presumes, without providing justification, that swimmers cannot be the most knowledgeable about which times of day are safest for swimming
(E) fails to take into account the possibility that the number of shark attacks at night would increase dramatically if more people swam at night

bidskamikaze · Answer

Clearly E.
(A) irrelevant.
(B) reliability of sources is not discussed.
(C) Doesn't matter. How swimmers feel is in no way related to number of shark attacks during day or night in the context of this passage.
(D) Swimmer's knowledge is not discussed.
(E) Bingo!

deepverma · Answer

Background:  This region’s swimmers generally swim during the day as they feel safe swimming during daylight hours.
 Premise: all recent shark attacks on swimmers in the area have occurred during the day,
 Conclusion:  it is not more dangerous to swim here at night than during the day.
 Prethink:  Premise shows data for only daytime-swimmers and conclusion is about night times. Missing data: Number of Night-swimmer getting attacked > Number of day-swimmer getting attack.

The reasoning in the argument is  most vulnerable  to criticism on the grounds that it

(A) overlooks the possibility that  some  sharks are primarily nocturnal hunters : OK but some means?how many? it can be none to many also no. of night-attack is missing 
(B) bases its conclusion on evidence from an  unreliable source : OOS 
(C) overlooks the possibility that swimmers might feel anxiety caused by not being able to see one’s surroundings in the dark :  Anxiety is out of scope 
(D) presumes, without providing justification, that swimmers cannot be the most knowledgeable about which times of day are safest for swimming :  Knowledge is Out of scope 
(E) fails to take into account the possibility that the number of shark attacks at night would increase dramatically if more people swam at night:  Correct

stne · Answer

Shark attacks have occurred during the day because swimmers are present only during the day, if there are no swimmers at night how can Sharks attack during the night. If there were an equal number of people swimming during the day and night then the attacks could be compared and a conclusion could be reached. However, since there are no swimmers at night there is no scope for the Sharks to attack.

Hence we cannot say that it is  NOT  more dangerous to swim during the night.

Only Option E is in line with this thought.

Ans- E

Hope it's clear.

thouhid · Answer

Stimulus Breakdown:
Gotta watch out for those sharks! People think they'll eat you if you swim at night but, since all recent attacks have happened during the day, they're wrong.

Answer Anticipation:
We want to compare the safety of day swimming vs. night swimming (the latter of which deserves a quiet night, for all you REM fans). We know more attacks have happened during the day. In order to compare the overall safety, we need to know the overall number of swimmers at day and at night. If no one swims at night, of course no shark attacks happen then! This flaw can be viewed either as a variety of sampling or comparison flaw.

Correct answer:
(E)

Answer choice analysis:
(A) The argument states night swimming isn't more dangerous than daytime swimming. Since we know some attacks have happened during the day, a few nocturnal hunters won't necessarily hurt the argument that the danger is about the same.

(B) Out of scope. The source isn't mentioned, so it must be the author. While an unreliable narrator might explain The Usual Suspects, we're not allowed to question the author's reliability on the LSAT - just their logic. (Unless, of course, the LSAT gives you a specific reason to.)

(C) Out of scope. The argument is about safety, not anxiety. While the argument mentions anxiety, it's the counterpoint to the author's argument, and we care about the author's argument.

(D) Out of scope. Similar to (C). The argument doesn't assume that the swimmers are wrong; it uses statistics surrounding shark attacks to do so. It uses the statistics poorly, but that's enough to say that the author doesn't just dismiss their opinion.

(E) Bingo. The author talks relative safety levels based on the absolute number of shark attacks. In doing so, the author assumes similar numbers of people swim during the day and at night. This answer deals with the possibility that no one swims in the ocean at night (probably because of the sharks

).

Takeaway/Pattern: If a conclusion compares two things, you need to know that the elements of that comparison are, well, comparable.

). Takeaway/Pattern: If a conclusion compares two things, you need to know that the elements of that comparison are, well, comparable.

homersimpsons · Answer

This is a question stem asking us to identify a flaw with the argument.

This argument concludes that, contrary to pop. opinion, it is not more dangerous to swim at night than the day.

Why?

More people have been attacked by sharks during the day than at night.

That would be pretty good evidence except for the fact that we are told the region's swimmers generally swim in the day.

Just to put numbers on this:

Lets say that during the day...

20 out of 100 swimmers are attacked. So a 20% rate.

Then at night we have 1 out 2 swimmers being attacked. So a 50% rate.

We would expect more people to be attacked during the day due to more people actually swimming during the day. This argument overlooks the possibility that if those 100 people swam at night instead of the day, that 20% rate could be a 50% rate, in which case you would have 50 people attacked.

That is what (E) is stating.

PrinceVegeta · Answer

This region’s swimmers generally swim during the day because they are too afraid of sharks to swim after dark but feel safe swimming during daylight hours. Yet all recent shark attacks on swimmers in the area have occurred during the day, indicating that, contrary to popular opinion, it is not more dangerous to swim here at night than during the day.

The reasoning in the argument is most vulnerable to criticism on the grounds that it

(A) overlooks the possibility that some sharks are primarily nocturnal hunters
  if only some  sharks are nocturnal hunters,that may or may not pose a great danger. if only one shark attacks, then the author would be right if all sharks attack then author will be wrong. since there are two possibilities this is not the correct answer  
(B) bases its conclusion on evidence from an unreliable source
  we must always take the statements in the stimulus as true  
(C) overlooks the possibility that swimmers might feel anxiety caused by not being able to see one’s surroundings in the dark
  this is not talking about the sharks but the anxiety of the swimmers. this doesn't hurt the authors reasoning so this cannot be the answer  
(D) presumes, without providing justification, that swimmers cannot be the most knowledgeable about which times of day are safest for swimming
  this is completely out of context.  
(E) fails to take into account the possibility that the number of shark attacks at night would increase dramatically if more people swam at night
  If this happened then the author's reasoning will be wrong for sure  
ANSWER-  E

VerbalBot · Answer

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This region’s swimmers generally swim during the day because they are

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This region’s swimmers generally swim during the day because they are

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