Self-study
Support The number of serious traffic accidents (accidents resulting in hospitalization or death) that occurred on Park Road from 1986 to 1990 was 35 percent lower than the number of serious accidents from 1981 to 1985. ███ █████ █████ ██ ████ ████ ███ ███████ ██ █████ ██████ ███ █████████ ██ ███ █████ █████ ███ ██ ███ ████████ ██ ███████ ██████████
Summarize Argument
The author concludes that a speed reduction caused the decrease in serious accidents on Park Road. This is because the number of serious accidents was significantly lower in the 5 years after the speed reduction than in the 5 years before the speed reduction.
Notable Assumptions
Based solely on a correlation between the speed reduction and the reduction in serious accidents, the author assumes that the former caused the latter. This means assuming there was no hidden third factor occurring at the same time that was the real reason for the decrease (e.g. road repairs, better driving instruction, less traffic, and so on).
14.
Which one of the following ███████████ ██ █████ ████ ███████ ███ █████████
a
The number of ████████ ███████ ██████ ████████ ██ ████ ████ ████████ ███████ ████████ ████ ████ ██ █████
Even if speeding tickets remained the same, the limit indeed dropped in 1986, so speeders were likely still driving more slowly. This doesn’t weaken the argument without more information.
Illusory inconsistency
Illusory inconsistency
Answer is attractive because it seems to (but doesn't actually) contradict the premises or conclusion.
b
Beginning in 1986, ██████ █████████ ████ ████ ████ ████ ██████████ ████ ██ ████ ███ ████████ ██████
In other words, the decrease was not due to a higher police presence. Eliminating an alternative cause doesn't weaken the argument; if anything, it strengthens.
Failed alternate explanation
Failed alternate explanation
Weaken Qs: Answers that try to introduce an alternate explanation, but fall short, or try to explain a different phenomenon.
Strengthen Qs: Answers that try to eliminate an alternate explanation, but fall short, or try to eliminate an explanation for a different phenomenon.
c
The annual number ██ ████████ █████ ████ ████ █████████ █████████████ ███ ████████ ████ ████ ██ █████
This gives us another reason why there were fewer serious accidents near the end of the decate than near the start: fewer cars. By providing an alternative cause, this weakens the argument.
Alternate explanation
Alternate explanation
Weaken: Introduce or support an alternate explanation for a phenomenon.
Strengthen: Helps to eliminate an alternate explanation for a phenomenon.
d
The annual number ██ █████████ ██ ████ ████ ████ ███ ███ ██████ ██ ███████████████ ████████ ███████ ████████ ████ ████ ██ █████
We only care about serious accidents, which result in either death or hospitalization. And we already know that serious accidents decreased, so this isn't relevant.
Illusory inconsistency
Illusory inconsistency
Answer is attractive because it seems to (but doesn't actually) contradict the premises or conclusion.
e
Until 1986 accidents ████ ██████████ ██ █████████ ████ ██ ████ ████████ ██ ██ ████████ ████████ █████
In other words, serious accidents decreased even despite the more inclusive definition. This doesn't weaken the argument, although it may well strengthen it.
Failed alternate explanation
Failed alternate explanation
Weaken Qs: Answers that try to introduce an alternate explanation, but fall short, or try to explain a different phenomenon.
Strengthen Qs: Answers that try to eliminate an alternate explanation, but fall short, or try to eliminate an explanation for a different phenomenon.