Recent studies have demonstrated that smokers are more likely than non

Question

Recent studies have demonstrated that smokers are more likely than nonsmokers to develop heart disease. Other studies have established that smokers are more likely than others to drink caffeinated beverages. Therefore, even though drinking caffeinated beverages is not thought to be a cause of heart disease, there is a positive correlation between drinking caffeinated beverages and the development of heart disease.

The argument’s reasoning is most vulnerable to criticism on the grounds that the argument fails to take into account the possibility that

The argument’s reasoning is most vulnerable to criticism on the grounds that the argument fails to take into account the possibility that

(A) smokers who drink caffeinated beverages are less likely to develop heart disease than are smokers who do not drink caffeinated beverages

(B) something else, such as dietary fat intake, may be a more important factor in the development of heart disease than are the factors cited in the argument

(C) drinking caffeinated beverages is more strongly correlated with the development of heart disease than is smoking

(D) it is only among people who have a hereditary predisposition to heart disease that caffeine consumption is positively correlated with the development of heart disease

(E) there is a common cause of both the development of heart disease and behaviors such as drinking caffeinated beverages and smoking

Bunuel · Accepted Answer

EXPLANATION FROM Fox LSAT

No, no… you haven’t proven there’s a correlation between anything and anything else. I’m not buying it.

This argument basically proceeds like this:
 
 Premise 1: “A (smoking) and B (heart disease) are correlated.” I have no problem with this. It’s a premise of the argument, and we should accept it as fact. 
 Premise 2: “A (smoking) and C (drinking coffee) are correlated.” I have no problem with this either. It’s a premise of the argument, and we should accept it as fact. 
 Conclusion: “B (heart disease) and C (drinking coffee) are correlated.” I have a huge problem with this. It’s not a premise, so we should  not  accept it as fact. It’s the conclusion of the argument, which is usually where the bullshit comes in. Here, the conclusion is  suggested  by the facts, but definitely not  necessarily proven  by the facts. So we object. It  might  be true, but the given facts certainly don’t prove it.

An example might clarify why B and C might not necessarily be correlated. What if the argument had said this:
 
 Premise 1: “A (living in San Francisco) and B (seeing a buck naked dude walking down the street in broad daylight) are correlated.” (This is true.) 
 Premise 2: “A (living in San Francisco) and C (being wealthier than average) are correlated.” (This is also true.) 
 Conclusion: “Therefore B (seeing a buck naked dude walking down the street in broad daylight) and C (being wealthier than average) are correlated.” (This is obviously nonsensical.)

How’s that? Make more sense? General principle: Just because A and B are correlated, and A and C are also correlated, does  not  mean that B and C are correlated.

The question asks us criticize the argument by finding a possibility “that the argument fails to take into account.” I think the answer might be something like “B and C are negatively correlated,” or “B reduces C,” or “C reduces B.”

A) Yep. This is “C reduces B.” If it’s true that smokers who drink caffeine are  less  likely to get heart disease than are smokers who do not drink caffeine, then that’s a pretty good attack on the idea that caffeine and heart disease are correlated. I like this answer a lot.

B) Nah. Who gives a **** if there is a “more important factor”? A more important factor wouldn’t do anything to weaken the idea that B and C are correlated. B and C can still be correlated, even if X and B are even more correlated.

C) This would strengthen the argument. We’re looking for a weakener.

D) Even if this is true, it doesn’t weaken the argument. Actually, it strengthens the argument by saying that, for at least one segment of the population, there  is  a correlation between caffeine and heart disease. We wanted to weaken that correlation, not strengthen it.

E) A common cause between B and C would  strengthen  the idea that B and C are correlated.

Our answer is A.

sivatx2 · Answer

From the conclusion, author say
i). That caffeinated drinks does not cause heart disease may not be true( by the usage of thought)
ii). caffeinated drinks (positive correlation) -----> heart disease.

To undermine above argument we need either of the following:

1. caffeinated drinks less likely to cause heart disease. (less correlation)
2. percentage of those who consumed both (caffeinated drink + smoking) and got heart disease is less than the percentage of those did only smoking(NO caffeinated drink) and got heart disease

(A) smokers who drink caffeinated beverages are less likely to develop heart disease than are smokers who do not drink caffeinated beverages 
 This is exactly the point 2, in our analysis and probably the best choice.. Keep

(B) something else, such as dietary fat intake, may be a more important factor in the development of heart disease than are the factors cited in the argument 
 dietary fat is irrelevant to the argument. Remember we need to prove/disprove between caffeinated drinks & smoking. Eliminate

(C) drinking caffeinated beverages is more strongly correlated with the development of heart disease than is smoking 
 This strengthens the argument. Eliminate

(D) it is only among people who have a hereditary predisposition to heart disease that caffeine consumption is positively correlated with the development of heart disease 
 This may weaken only a little bit, as hereditary predisposition maybe just a subset and may not weaken in entirety. Eliminate

(E) there is a common cause of both the development of heart disease and behaviors such as drinking caffeinated beverages and smoking 
 Root cause may be same for heart disease, but it does not change anything to the argument on the effect of caffeinated drink and/or smoking. Eliminate

So, the best answer choice is A.

Sumi1010 · Answer

Heart Disease : Smokers > Non-smokers
Drinking caffeinated beverage : Smokers > Non-smokers

Conclusion :  There is a positive  correlation  between drinking caffeinated beverages and the development of heart disease.

Pre-think  : This question asks us to decipher the "flaw" in the reasoning (and not to weaken the argument), hence the choices are not supposed to bring in additional information.

Let's say there are 1000 smokers and 1000 Non-smokers.
Let's say, of the first 500 smokers, 300 got Heart disease. And, of the first 500 Non-smokers, 200 got heart disease.

Again, 
Of the next 500 smokers, 400 drink caffeinated beverage. Of the next 500 Non-smokers, 200 drink caffeinated beverage.

Can we conclude that there is a correlation between drinking caffeinated beverages and the development of heart disease?  
- Definitely Not. 
The two sets are independent from each other. Thus, this conclusion will not be right.

Now, let's look at the choices-

(A)  smokers who drink caffeinated beverages  are less likely to develop heart disease than are smokers who do not drink caffeinated beverages
 This choice says that the argument is flawed because it did not consider about the overlapping set of the people i.e. "smokers who drink caffeinated beverages + got the heart diseases". 
Until there is no overlapping of both the traits, we can't make a certain conclusion, and that's why there is a flaw. 
(B)  something else,  such as dietary fat intake, may be a more important factor in the development of heart disease than are the factors cited in the argument
 As soon as i see "something else" I will eliminate the choice. 
Reason : "something else" contributes as factor to impact the argument in case of "causation" and not "correlation". 
(C) drinking caffeinated beverages is  more  strongly correlated with the development of heart disease than is smoking
 The "degree" of correlation is not the concern of the argument.  
(D) it is  only among people  who have a hereditary predisposition to heart disease that caffeine consumption is positively correlated with the development of heart disease
 This choice says that  for a certain type of people , the "correlation" exists. 
The argument says that - the correlation, in general, exists.

Thus, this choice tries to weaken the argument's conclusion by giving an additional information (that breaches the generalisation). 
This choice does not point out the flaw. 
(E) there is a  common cause  of both the development of heart disease and behaviors such as drinking caffeinated beverages and smoking
 The argument talks about "correlation" and not "causation" 
  Note: In many of the weakening problems, we see that "correlation" is misinterpreted as "causation". 
However, "causation" itself is a "correlation"; hence, vice-versa can't be a misinterpretation  .

IMO  A

Crytiocanalyst · Answer

(A) smokers who drink caffeinated beverages are less likely to develop heart disease than are smokers who do not drink caffeinated beverages
This is definitely the answer and helps us understand the fact there is no definitive corelation between caffeniated drinks and heart diseases

(B) something else, such as dietary fat intake, may be a more important factor in the development of heart disease than are the factors cited in the argument
This may be the case but this intself doesn't help us eleminate the fact that dietary habits do not cause heart diseases therefore out

(C) drinking caffeinated beverages is more strongly correlated with the development of heart disease than is smoking
This lends strength to the argument

(D) it is only among people who have a hereditary predisposition to heart disease that caffeine consumption is positively correlated with the development of heart disease
This is thoroughly out of context and doesn't help us evaluvate the argument therefore out

(E) there is a common cause of both the development of heart disease and behaviors such as drinking caffeinated beverages and smoking
Restating the premise doesn't help the cause therefore out

Therefore IMO A

craghav1985 · Answer

But the option hinges on the likelihood, meaning the degree may vary from “more to less” but it doesnt change the fact that it leads to it, no matter how small the effect is. Isnt that strengthening the fact that caffeine causing heart disease? Say in smokers it may be only 50% or say 90% of the times true but in no -smokers it may be 95%. But that doesnt mean it doesnt.

Please explain

Posted from my mobile device

VerbalBot · Answer

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Recent studies have demonstrated that smokers are more likely than non

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