An author writing a book about birth order advertised in his local pap

Question

An author writing a book about birth order advertised in his local paper for people who were first born. Fifty people consented to be interviewed and assessed for certain personality traits. As the writer suspected, the interview results and personality assessments showed that first-borns were more goal oriented and serious-minded than random samples of the general public. These findings support the conclusion that people are affected by their birth order.

Which one of the following selections, if true, points out the most critical weakness in the method used by the author to investigate birth order characteristics?

(A) Last born children are typically more laidback and calm than their older siblings.

(B) The interviews and assessments were performed by an outside firm, not by the author.

(C) People who saw the newspaper ad were not more likely to be first born than the number of first-born people in the population in general.

(D) The author’s subsequent contact with people who were middle children or last born tended to reinforce his initial impression of the character traits of people who were not first born.

(E) People who are not goal-oriented and serious-minded were not as likely to respond to the author’s newspaper ad nor were they as likely to agree to participate in the study.

Bunuel · Accepted Answer

Official Explanation

The argument generalizes from a small sample to the population as a whole. If the sample is shown not to be representative of the general population, then the author’s conclusion is weakened. If goal oriented and serious-minded people were more likely to respond to the author’s newspaper ad and agree to be studied, then this shows that the sample was not representative of the general population.

Selection (E) points out this weakness and is the correct answer.  If first-born people who were not serious-minded and goal-oriented simply didn’t respond to the newspaper ad, then the sample studied by the author was not representative of firstborns in the general population. Rather, his sample consisted heavily of first-borns who had those two personality traits, and thus his conclusion would be seriously flawed.

Selection (C) is tempting. Although it goes to the core of the question, that is, how representative is the study sample of the general public, it actually strengthens the writer’s argument. Selection (C) suggests that the newspaper ad was exposed to the general public as opposed to a more limited audience.

HoneyLemon · Answer

is it E ?
An author writing a book about birth order advertised in his local paper for people who were first born. Fifty people consented to be interviewed and assessed for certain personality traits. As the writer suspected, the interview results and personality assessments showed that first-borns were more goal oriented and serious-minded than random samples of the general public. These findings support the conclusion that people are affected by their birth order.

Which one of the following selections, if true, points out the most critical weakness in the method used by the author to investigate birth order characteristics?

Fifty people consented to be interviewed and assessed for certain personality traits.
What if serious and goal oriented people only give consent to be interviewed ? in that case the argument will weakened ..

(A) Last born children are typically more laidback and calm than their older siblings.

(B) The interviews and assessments were performed by an outside firm, not by the author.

(C) People who saw the newspaper ad were not more likely to be first born than the number of first-born people in the population in general.

(D) The author’s subsequent contact with people who were middle children or last born tended to reinforce his initial impression of the character traits of people who were not first born.

(E) People who are not goal-oriented and serious-minded were not as likely to respond to the author’s newspaper ad nor were they as likely to agree to participate in the study.

Saasingh · Answer

Looks like its E.

The weakness is that the sample is skewed. The author bases his conclusion on the respondents (the first borns who displayed goal oriented traits). However, if these people were the only one likely to respond, and the people who are NOT first born didnt respond only, our test sample is skewed to give a favorable result. I.e our sample is unfair.

winterschool · Answer

An author writing a book about birth order advertised in his local paper for people who were first born. Fifty people consented to be interviewed and assessed for certain personality traits. As the writer suspected, the interview results and personality assessments showed that first-borns were more goal oriented and serious-minded than random samples of the general public. These findings support the conclusion that people are affected by their birth order.

Which one of the following selections, if true, points out the most critical weakness in the method used by the author to investigate birth order characteristics?

(A) Last born children are typically more laidback and calm than their older siblings.  Incorrect

only a part of study cant weakens argument

(B) The interviews and assessments were performed by an outside firm, not by the author.  Incorrect

but if it is true, than who done this study is not a fact

(C) People who saw the newspaper ad were not more likely to be first born than the number of first-born people in the population in general.  Incorrect

advertise was for first born, so support argument

(D) The author’s subsequent contact with people who were middle children or last born tended to reinforce his initial impression of the character traits of people who were not first born.  Incorrect

support argument

(E)  People who are not goal-oriented and serious-minded were not as likely to respond to the author’s newspaper ad nor were they as likely to agree to participate in the study.   Correct

as a result, others peoples character traits were absent in authors study. so, argument conclusion is not acceptable

Shadyshades · Answer

(E) People who are not goal-oriented and serious-minded were not as likely to respond to the author’s newspaper ad nor were they as likely to agree to participate in the study.

E it is.

But I think it's not an air tight weakened option if i observe closely. 
People who are not goal -oriented and serious minded who didn't respond to the ad can also be middle or last born people. So all i am saying a person can not be traced by his
birth order. Oops(Jim Carrey's expression), did i just answer myself that it's remarkably air tight weakened answer. Ooo... La La La !

VerbalBot · Answer

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An author writing a book about birth order advertised in his local pap

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An author writing a book about birth order advertised in his local pap

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