Q13 - A recent study of 10,000

[ohthatpatrick]

Your thinking is valid.

We could say that (A) weakens somewhat by making "most" of the sample come from a potentially unrepresentative set of circumstances.

But it's highly speculative for us to assume we'd get different results in different speed limit areas. So this answer would only be correct if NOTHING else weakened, since it creates such a small amount of doubt.

The other think watering down its effect is that it says "MOST" of the accidents analyzed come from a high speed limit area. That still leaves room for 4,999 of the 10,000 accidents to come from "more representative" areas.

Since the study results that the author is using as evidence come from all 10,000 data points, (A) would still allow the study to have looked at a wide range of speed limit areas.

Hope this helps.

[Sylvia11]

This is more of an English comprehension question but I don't get what the conclusion is saying and how the argument is flawed. The conclusion states "one is less likely to be injured in an automobile accident if one drives a large car rather than a small car." From the evidence, isn't this true? Given the study looked at a sample of accidents, it was found that when getting into an accident, you're more likely to be injured if you're driving a small car than a large car. To make the question work, it seems like you have to ignore "... in an automobile accident..."

[ohthatpatrick]

The evidence shows that "If you were in an accident, you were less likely to be injured in a large car."

The shift in the conclusion to saying, "If you drive a large car, you are less likely to be injured in an accident", is making a different claim.

Say that you drive a big car and I drive a small one: if we each got into an accident, I would be more likely to get injured.

But also say, as (D) does, that you get into way more accidents than I do (my small car makes it easier to stop or swerve out of the way). When you add that to the equation, who is more likely to be injured:
you, who drives a large car and gets into frequent accidents (although usually doesn't get hurt in them)
or
me, who drives a small car and rarely gets into accidents (but would probably get hurt if I did get into one)?

It's possible that the large car driver overall has a higher chance of being injured than the small car driver.

Here's a different metaphor:
Some evil villain offers you this choice ...
1. you get tortured every time he flips a coin and it lands on heads.
or
2. you get tortured every time he rolls a six-sided die and it lands on 1 or 2.

Which choice would you take?

The 2nd of course. In the first one, I have a 50% chance of being tortured each time. In the 2nd one, I only have a 33.3% chance of being tortured.

But now say the evil villain goes on and says,
"you can choose either method, but you should know that I only plan to flip the coin twice, whereas I plan the roll the die ten times."

Now the 1st option sounds better.

The 1st option, high probability of pain but not as frequently occurring, is small car.
The 2nd option, low probability of pain but more frequently occurring, is large car.

The conclusion is flawed because without knowing how many accidents large cars vs. small cars are involved in, we don't know whether we'd be safer taking the "once in a while, but high chance of bad" or the "low chance of bad, but frequently occurring"

Does that make sense?