- Thu Feb 20, 2014 12:00 am
#32457
Complete Question Explanation
Method of Reasoning—CE. The correct answer choice is (A)
Here, the author looks to historical records for evidence about the relationship between food availability and newborn health. A review of records from 1850 to 1900 details a correlation between birth weights and the success of crops the year earlier. From this correlation, the author concludes that there is a causal connection between the amount of food available to the mother during her pregnancy and the health of the newborn. This relationship can be diagrammed as:
more food = more food available to the mother during pregnancy
better health = better health of the newborn at birth
Cause
Effect
more food 
better health
It should come as no surprise that this causal conclusion is flawed. First, the only support for the conclusion is a correlation, which we know cannot provide proper support for a valid causal conclusion. This is true even when the conclusion is moderated, as is the conclusion here, that newborn health depends to a large extent on food available to the mother.
In addition to that flaw, the terms in the argument shifted from the premise to the conclusion. The premise mentioned birth weights while the conclusion talked about newborn health. Also, the author gave evidence about crop success, yet reached a conclusion about food availability. While certainly these term pairings are related, they are not synonymous. As a matter of common sense, we can say that birth weight is just one factor having to do with newborn health, and crop success is just one factor in food availability.
The question stem tells us that this is a Method of Reasoning question. Our prephrase is that this was a flawed, causal argument, in which the causal conclusion was supported only by evidence of a correlation, and the terms shifted from the premise to the conclusion.
Note that the question stem does not identify this argument as flawed. While a Flaw in the Reasoning question will certainly display flawed argumentation, the conclusion in a Method of Reasoning question may be either valid or flawed.
Answer choice (A): This is the correct answer choice, because it describes both flaws. The “correlation between two phenomena” refers to the correlation between crop success and birth weights, while the causally connected phenomena are food availability and newborn health.
Answer choice (B): This is a Half Right, Half Wrong answer choice. Although the first part of this answer accurately refers to the correlation between crop success and birth weight, the second part of the answer mistakenly states that food availability was cited as the sole cause of newborn health. Rather the conclusion was that newborn health depends to a large extent on food availability.
Answer choice (C): This answer choice is attractive, because it properly describes the historical nature of the evidence and the present tense language of the conclusion. However, the conclusion was not that the historical correlation continues, but rather that the causal relationship remains the case.
Answer choice (D): The “two phenomena” observed in historical records were crop success and birth weights. The argument did not infer that these two phenomena resulted from a common cause.
Answer choice (E): Although the author did infer the existence of a causal connection, the evidence was a correlation, not a separate causal relationship.
Method of Reasoning—CE. The correct answer choice is (A)
Here, the author looks to historical records for evidence about the relationship between food availability and newborn health. A review of records from 1850 to 1900 details a correlation between birth weights and the success of crops the year earlier. From this correlation, the author concludes that there is a causal connection between the amount of food available to the mother during her pregnancy and the health of the newborn. This relationship can be diagrammed as:
more food = more food available to the mother during pregnancy
better health = better health of the newborn at birth
Cause
Effect more food
better health It should come as no surprise that this causal conclusion is flawed. First, the only support for the conclusion is a correlation, which we know cannot provide proper support for a valid causal conclusion. This is true even when the conclusion is moderated, as is the conclusion here, that newborn health depends to a large extent on food available to the mother.
In addition to that flaw, the terms in the argument shifted from the premise to the conclusion. The premise mentioned birth weights while the conclusion talked about newborn health. Also, the author gave evidence about crop success, yet reached a conclusion about food availability. While certainly these term pairings are related, they are not synonymous. As a matter of common sense, we can say that birth weight is just one factor having to do with newborn health, and crop success is just one factor in food availability.
The question stem tells us that this is a Method of Reasoning question. Our prephrase is that this was a flawed, causal argument, in which the causal conclusion was supported only by evidence of a correlation, and the terms shifted from the premise to the conclusion.
Note that the question stem does not identify this argument as flawed. While a Flaw in the Reasoning question will certainly display flawed argumentation, the conclusion in a Method of Reasoning question may be either valid or flawed.
Answer choice (A): This is the correct answer choice, because it describes both flaws. The “correlation between two phenomena” refers to the correlation between crop success and birth weights, while the causally connected phenomena are food availability and newborn health.
Answer choice (B): This is a Half Right, Half Wrong answer choice. Although the first part of this answer accurately refers to the correlation between crop success and birth weight, the second part of the answer mistakenly states that food availability was cited as the sole cause of newborn health. Rather the conclusion was that newborn health depends to a large extent on food availability.
Answer choice (C): This answer choice is attractive, because it properly describes the historical nature of the evidence and the present tense language of the conclusion. However, the conclusion was not that the historical correlation continues, but rather that the causal relationship remains the case.
Answer choice (D): The “two phenomena” observed in historical records were crop success and birth weights. The argument did not infer that these two phenomena resulted from a common cause.
Answer choice (E): Although the author did infer the existence of a causal connection, the evidence was a correlation, not a separate causal relationship.
The difference is that B talks about a sole cause, which the stimulus does not assert (the stimulus says "depends to a large extent on"). A states that a causal connection is asserted, which is true, it's just not claimed to be the only cause.
