Sunday, 19 July 2015

RC 2

A study based on a year-long analysis of data from an extensive
    mobile phone network has produced interesting information that
    might be of use to epidemiologists and social scientists. The
    data, according to the researchers, might shed light, for example,
5    on how diseases and information (or rumors) are transmitted
    through social networks.

    Researchers ranked the link between a pair of phone users on
    the basis of the total time spent talking to each other.
    'Strong' links exist between members of a close social group.
10  'Weak' links tend to be more long range and join individuals
    from different social groups.

    The researchers observed a dramatically different effect when
    they removed links in the network in rank order, depending on
    whether they removed links starting with the strongest or with
15  the weakest. To their surprise, removing the strong links first
    had little effect on the overall structure of the network. But
    removing weak links first split the network into a series of
    unconnected islands, with individual users linked to a small
    collection of other phone users.

20  Thus the researchers have hypothesized that the weak links
    (the more tenuousCONNECTIONS between individuals from
    different social groups) might be very important in
    maintaining wider social cohesion. If you lose contact with
    casual acquaintances you may fragment your social circle, but
25  if you stop talking to your brother there might be less
    visible impact on the structure of your social network.

1. The passage offers support for which of the following positions?

A. 'Weak' links are more important than 'strong' links
B. Links between family members would be likely to be disrupted by terminating 'weak' links
C. Some people believe that phone-network patterns could be useful to social scientists
D. Information transmission through phone networks is essentially the same as information transmission through face-to-face contact
E. The 'strong' links are between geographically close individuals

2. In the last sentence the author apparently intends to

A. make the ideas more specific to enhance the reader's understanding
B. reinforce the researchers' conclusions
C. provide a practical illustration of the meaning of a strong link
D. generalize the argument to make it more appealing
E. concretize an argument about the usefulness of the current research

3. Which of the following can be inferred from the passage?
(Select ALL answer choices thatAPPLY)

A. The researchers had not anticipated the specific effects of removing weak links
B. The phone-network studied had the same number of users throughout the study
C. The phone users were unaware of the study

    The standard methods of science proceed from observations to
    hypotheses to testing these hypotheses in controlled experiments.
    However, it would be a mistake to suppose that every hypothesis
    that comes out of observation lends itself to rigorous scientific
5    scrutiny. There are, in fact, many questions that can be asked of
    science that science is not in a position, for one reason or
    another, to answer. (Such unanswerable questions cannot strictly
    be termed hypotheses, since a hypothesis must be testable.)

    The recent debate over melanoma (skin cancer) screening provides
10  an interesting example of this area of 'science that is not
    scientific' or 'trans-science' as a few eminent thinkers have
    termed it. Let's start with the observations. There has been an
    increase in the number of early-stage melanoma cases over the
    last twenty years. The incidence, measured in cases per
15  thousand people, in the United States has doubled since 1896.
    As a result of theREPORTED numbers, some physicians recommend
    screening for melanoma. The 'hypothesis' that is implied here
    is that screening for melanoma will decrease the death rate from
    the disease. But how do we test it?

20  The conventional way to evaluate the effectiveness of a medical
    technique is the double blind trial. In this case we would have
    to assign some people to receive screening and some control
    people would not be screened. Then we would look at the death
    rate for melanoma in the two groups. The problems are logistic
25  and ethical. If the answers are to reach statistical significance
    we need very large numbers and we need to follow people over
    whole lifetimes, neither of which is practical. And how do we
    decide who is to receive what might be a life-saving screening
    and who will be denied its potential benefits?

30  The data collected thus far on the effectiveness of screening is,
    not surprisingly, equivocal.

4. The author would apparently agree with which of the following?
(Select ALL answer choices thatAPPLY)

A. The effectiveness of screening for melanoma is not proven
B. Double blind trials are the best method to evaluate
C. The death rate from melanoma is rising rapidly

5. The word in bold-face in paragraph 2 is placed in inverted commas to

A. Suggest that the contention in the same sentence cannot be tested scientifically
B. Emphasize the importance of framing hypotheses correctly
C. Draw attention to the main word in the sentence
D.INDICATE that the author is using someone else's view
E. Add weight to the author's view of the correct way to evaluate melanoma screening

6. Which of the following does the author mention as an example / examples of the 'reasons' mentioned in the highlighted sentence?

A. Insufficiency of sample size
B. Ethical considerations
C. Ambiguous data

7. Answer this question based on the information in the paragraph below.

French cuisine is highly regarded all over the world. Yet in Paris there are more American restaurants selling burgers and fries (which many people now class as 'junk food') than there are in any other European capital city. Obviously the French are very fond of 'junk food', and are not too proud to eat it.

Which of the following, if true, would most weaken the author's contention?

A. There are also a larger number of Lebanese restaurants in Paris than there are in other European capital cities
B. French Cordon Bleu cuisine is very expensive
C. The number of French tourists eating in New York burger restaurants is very low
D. Junk food is actually has high nutritional value when eaten in moderation
E. There are an unusually large number of American tourists in Paris who eat at burger joints

8. Answer this question based on the information in the paragraph below.

It is not unusual to see the ball fall into a black slot on a roulette wheel four times in a row. But for it to fall five or six times in a row into the same color is very unusual. Therefore you canWIN MONEY by waiting for a run of five of the same color and then betting against that color.

If the roulette wheel in question is a fair wheel, which of the following observations or facts, if it were true, would best reveal a fallacy in the logic?

A. If there were a reliable way to win at roulette it would be well-known by now.
B. It is hard for a player to keep track of what went before for the timeREQUIRED.
C. The probability of getting a particular color decreases with the number of times the color has appeared.
D. The probability of getting a particular color is always the same no matter what has gone before.
E. A personWHO MAKES MONEY this way once or twice, will carry on to lose that money after a few more times.

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