Questions on the Dec 2007 LSAT--help!

[smiley111]

Hi everyone - I hope someone can help me out with these. Here are my questions with my thoughts noted...thank you guys

In 3 seperate studies researchers compared children who had slept  with night lights in their rooms as infants to children who had not. In the first study, the children who had slept with night lights proved more likely to be nearsighted, but the later studies found no correlation between the night lights and the nearsightedness. However, the children in the first study were younger than those in the later studies. This suggests that if night lights cause nearsightedness, the effect disappears with age.

which one of the following weakens the argument

A) a fourth study comparing infants who were currently sleeping with night lights to infants who were not did not find any correlation between night lights and nearsightednes
- So for this I was thinking that the 4th study showed results different from the 1st 3. If so--wouldnt this weaken the argument by saying that the findings are not consistent. If they were the 4th study would show the same results as before....D is correct for this prob

D) the 2 studies in which no correlation was found did not examine enough children to provide significant support for any conclusion regarding a causal relationship between night lights and nearsightedness
- the 2 studies part threw me off...this is the correct answer


Some doctors believe that a certain drug reduces the duration of episodes of vertigo, claiming that the average duration of vertigo for people who suffer from it has decreased since the drug was first introduced. However, during a recent 3 month shortage of the drug, there was no significant change in the average duration of vertigo. Thus, we can conclude that the drug has no effect on the duration of vertigo

which one of the following is an assumption required by the arg?

A) if a drug made a difference in the duration of vertigo a three month shortage of that drug would have caused a significant change in the average duration of vertigo

C) a period of time greater than three months would not have been better to use in judging whether the drug has an effect on the duration of vertigo

- So for this I was thinking that once you negate it it would say a period of over 3 months would have been better in judging whether this had an effect. I was thinking what if you had to wait 5 months to see a change....if so then wouldnt this destroy the argument. If 5 months is the time period then theyre not waiting long enough to make an assessment

D) changes in diet and smoking habits are not responsible for any change in the average duration of vertigo since the introduction of the drug

- for this one I was thinking this too would destroy the argument once negated. If they were responsible, then you cant owe the results solely to the fact that there was a 3 month shortage...there were other factors.
- The right answer is A


When bacteria degrade household cleaning products vapors that are toxic to humans are produced. Unfortunately household cleaning products are often found in landfills. Thus the common practice of converting landfills into public parks is damaging to human health

which one of the following is an assumption the environmentalist arg requires

A) in atleast some landfills that have been converted into public parks there are bacteria that degrage household cleaning products

B) converting a landfill into a public park will cause no damage to human health unless toxic vapors are produced in that landfill and humans are exposed to them

- A is correct but I dont know why I was stuck between the 2. I thought that B was actually stated but I dont know. Can anyone tell me their thoughts on why B is wrong.

Thanks guys,

Smiley111

[Atlas LSAT Teacher]

A) a fourth study comparing infants . . . .
- So for this I was thinking that the 4th study showed results different from the 1st 3. If so--wouldnt this weaken the argument by saying that the findings are not consistent. If they were the 4th study would show the same results as before....D is correct for this prob

For this answer choice, the fact that there was another study supporting the other two does not make them inconsistent.  The only inconsistency is the first study, which the conclusion tries to explain away.  Furthermore, the conclusion is that "if night lights cause nearsightedness", so we don't really care whether the lights do cause nearsightedness, but whether the effect wears off.

D) the 2 studies in which no correlation was found did not examine enough children to provide significant . . .
- the 2 studies part threw me off...this is the correct answer

It's referring to the two latter studies.  What this answer does is call into question the premise of the argument.  If the studies were flawed, then we can't rely on their findings. 

Make sense?

Some doctors believe that a certain drug reduces the duration of episodes of vertigo,

For this one, I already wrote up an explanation here: http://www.atlaslsat.com/forums/pt-53-s1-q13-some-doctors-believe-that-a-certain-drug-t507.html

I'll leave your last one for someone else, but e-mail me if nobody gets to it.  BTW, don't write out LSAT questions, LSAC gets angry.

[glob157]

But wait ! I thought (regarding the nearsightedness question) that in the LSAT, you are NOT supposed to try to weaken premises, but rather, weaken argument structure.

The fact that D (an answer that seems to do nothing but attacka a premise)
 is the correct answer indicates that its OK to attack a premise....  

Please explain.. Thanks !  

[smiley111]

Sorry, I am not able to give an explanation to your inquiry...

But I do have a problem with answer choice D

Why D confused me is because of the wording.

D states = the 2 studies in which no correlation was found did not examine enough children to provide significant support for any conclusion regarding a causal relationship between night lights and nearsightedness


I think this would be correct if the answer choice was worded like this:

the 2 studies in which no correlation was found did not examine enough children to provide significant support for any conclusion regarding " the relationship between night lights and nearsightedness disappearing with age."

Please let me know your thoughts and an explanation for why D is correct worded the way it was - Thank you

[llsatt1]

Sorry, I am not able to give an explanation to your inquiry...

But I do have a problem with answer choice D

Why D confused me is because of the wording.

D states = the 2 studies in which no correlation was found did not examine enough children to provide significant support for any conclusion regarding a causal relationship between night lights and nearsightedness


I think this would be correct if the answer choice was worded like this:

the 2 studies in which no correlation was found did not examine enough children to provide significant support for any conclusion regarding " the relationship between night lights and nearsightedness disappearing with age."

Please let me know your thoughts and an explanation for why D is correct worded the way it was - Thank you

Structure of the argument:

Test 1 ->  there might be a causal relationship
Test 2 and 3 -> did not find any evidence of a correlation or causal relationship so the problem may disappear with age

Based on test 2 and 3, test 1 could still be correct and the problem may disappear with age.

Answer choice:  however, if 2 and 3 are faulty experiments, the problem may not disappear with age.  This weakens the argument

[Atlas LSAT Teacher]

Yeah, I think lsatt1 boiled it down nicely.  The vast majority of weaken questions attack an assumption, but there some that attack a premise -- and here it's not suggesting that the premises are false, but that we cannot draw the inferences that have been drawn in the argument.

Regarding the proposed re-wording of the LSAT, the relationship in question is broadly whether nightlights cause nearsightedness, and yes, specifically about whether the effect wears off with age.  When it states "any conclusion", it includes one that focuses on issues regarding age.  Does that make sense?