Subway Crime

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Subway Crime

by sanp_l » Wed Oct 14, 2009 9:53 am
A year after the start an experiment to decrease crime in two high-crime subway stations by the installation of closed-circuit televisions, the experiment is being discontinued, city officials say the program has led to an increase in crime, citing the fact that following the installation, both stations showed increases in the number of crimes reported.
Which of the following, if true, most seriously weakens the claim of the city officials that the program has led to an increase in crime?
(A) The two subway stations had been chosen on the basis subway stations was higher than that of other high-crime subway stations not equipped with closed-circuit-television.
(B) The rate of increase in crimes reported for two subway stations was higher than that of other high-crime subway stations not equipped with closed-circuit television.
(C) The percentage of all crimes committed at the two subway stations that were reported rose as a result of increased instances of observations of crime on the closed-circuit televisions.
(D) The year in which the experiment was conducted was a year in which the total number of crimes reported in the city fell.
(E) Closed-circuit televisions installed in shops and stores throughout the city have proved to be useful in the prevention of shoplifting and burglaries.

OA: C

I thought D to be correct. Can anyone explain. No explanation for the answer has been provided.
Sandy
Source: — Critical Reasoning |

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Subway Crime

by November Rain » Wed Oct 14, 2009 10:28 am
Hi sanp_l

Let's see answers C and D so i can try to help you out:

D) The year in which the experiment was conducted was a year in which the total number of crimes reported in the city fell.

In my opinion, this answer is not correct because it gives more support to the theory that the cameras actually increased crime rate in the two subway stations. If you have a city where the crime rate decreased in all subway stations, except the two where you have installed the cameras, than it was probably this action that triggered a spike in the crime rate.

Now let's see C)

C) The percentage of all crimes committed at the two subway stations that were reported rose as a result of increased instances of observations of crime on the closed-circuit televisions.

This sentence means that the crimes didn't actually rise - the high number of crimes was already hapening in the past. It's just because there are now cameras wathcing them, is possible to count them more accuratly, which wasnt possible in the past. Therefore the cameras instalation was not responsible for these crimes.

Hope it helps. Let me know if you need further help :)

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by sanp_l » Wed Oct 14, 2009 11:22 am
Your explanation of as to why Option C is correct makes it clear to me. I missed what the option was actually trying to say. It didn't occur to me that the increased rate was due to increase in the crime watched on the installations. Thanks.
Sandy