OFFICIAL EXPLANATION
A telephone poll conducted over two states asked respondents whether their homes were ever cold during the winter months. 99% of respondents said they were never cold during the winter months. The pollsters published their findings, concluding that 99% of all homes in the United States have adequate heating.
Which of the following most accurately describes what might be a questionable technique employed by the pollsters in drawing their conclusion?Whether a question contains the words “weakens the argument,” or “undermines the conclusion,” or even “describes a questionable technique,” what it is really asking you to do is find a hole in the logic of the argument. And, as usual, there are three types of holes that the GMAT test writers are very fond of: statistical, causal, and analogical. Did you spot one of these as you read the passage?
Whenever you see an actual statistic in an argument (in this case, 99 percent), you should examine it closely: The pollsters are basing a statistic for the entire country on a poll conducted in only two states. If you didn’t spot this as you read the passage, don’t worry; you’ll spot it as you read the answer choices.
A. The poll wrongly ascribes the underlying causes of the problem.
This answer choice says there might be an alternate cause for the conclusion— but does this feel like a causal argument? Let’s hold onto this and keep reading.B. The poll assumes conditions in the two states are representative of the entire country.
Aha! This choice is saying there is a statistical flaw in the argument. What if the two states were located in the southern part of the United States? If the residents of Florida were warm in January, would that be representative of the rest of the country who might be freezing? This seems like it must be the best answer, but let’s keep reading to make sure.C. The pollsters conducted the poll by telephone, thus relying on the veracity of the subjects they spoke to.
While this might represent a weakness in their interviewing technique, the question to ask yourself is whether this is an inherent weakness in the way the pollsters drew their conclusion. It is not; eliminate it.D. The pollsters did not go to the houses in person, thus precluding the actual measurement of temperatures in the subjects’ homes.
Again, if the pollsters had measured the temperature in each of the houses they went to, their information would probably have been more accurate, but does this constitute a flaw in the way the conclusion was drawn? Nope. Cross this one off.E. The pollsters never defined the term “cold” in terms of a specific temperature.
This choice is nitpicking. While it might have been better if the pollsters had asked the respondents what temperature they considered cold, this wouldn’t really weaken the conclusion. The best answer is the second one.