CT10a UNIT 2 SECTION 4 Evaluating Argument

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CT10a UNIT 2 SECTION 4Evaluating Argument

• In Unit 2 you will be asked how to evaluate the
  use of Evidence, Examples and Explanations in an
  argument. You will ask questions such as these
• 1/ Is this evidence precisely relevant to the
  authors reason/conclusion?
• 2/ Does the evidence support the authors R/C?
• 3/ Are there other conclusions that could be
  supported by the evidence?
• 4/ Is this example typical of the issue the
  author is talking about?
• 5/ Does the example support the authors
  reasoning?
• 6/ Are there alternative, plausible explanations
  for this evidence?

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CT10b UNIT 2 SECTION 4Evaluating Argument

• In Unit 1 you were asked questions about the
  evidence itself. In Unit 2 you will be asked
  about the authors use of the evidence. You
  should not doubt the reliability or question the
  way the author has used it. This is a different
  task from asking about the reliability of the
  survey sampling, or the credibility of the source
  of the evidence, as you did in Unit 1.
• Evidence is often used in the form of numerical
  data, an estimate or a factual claim. It is used
  to develop or support a reason.
• Key question Does this evidence actually give
  us grounds to accept the authors reasons and
  conclusion?
• 1/ Is this evidence precisely relevant?
• 2/ Is this evidence sufficient?
• 3/ Is this evidence being used in a strong way?

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CT10c UNIT 2 SECTION 4Evaluating Argument

• The key to evaluating the use of evidence is to
  keep asking questions about the link between
  evidence and the reason or conclusion it is
  supposed to support.
• IS THE EVIDENCE RELEVANT?
• Relevant evidence is precisely focused on the
  reason it supports. It must be about precisely
  the same thing as the reason. It must cover the
  same timescales, and be about the same area or
  the same group of people to which the reason is
  referring. In everyday language we would count
  information about roughly the same topic as
  relevant, but in CT, relevant means PRECISE and
  focused on the reason.
• E.G. What evidence would support the claim that
  Hawkwood Towers is an academic school? The
  evidence that Hawkwood Towers is one of four
  schools in town is not precisely relevant to
  academia. But saying 80 of students achieve at
  least two A grades at AS level is precisely
  relevant to the school being academic.

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CT10d UNIT 2 SECTION 4Evaluating Argument

• IS THE EVIDENCE SUFFICIENT TO SUPPORT THE
  CONCLUSION?
• Evidence which is sufficient to support a
  conclusion is enough, and strong enough, to give
  support to a conclusion.
• Using the previous example of Hawkwood towers,
  the AS results were relevant evidence to the
  school being academic but not sufficient as we
  would also need the A2 and University entrance
  results.
• One particular form of insufficiency is the
  unreasonably selective use of evidence available
  to us. If the author ignore vast quantities of
  evidence that might oppose his argument and
  select only that which supports his argument, he
  is being unreasonable and not providing
  sufficient evidence.
• You may be asked to judge whether an author has
  been selective.

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CT10e UNIT 2 SECTION 4Evaluating Argument

• IS THIS EVIDENCE USED IN A STRONG WAY?
• If the evidence is precisely relevant, then you
  can mention this is a strength.
• If the evidence is sufficient, you can mention
  this as a strength.
• E.G. Research over 40 years and hundreds of
  thousands of people consistently shows that
  people who smoke are significantly more likely to
  get lung cancer than no-smokers. We can
  therefore, fairly safely conclude that smoking is
  a contributory factor of lung cancer.
• In the above example, the evidence is precisely
  focused on the conclusion, which makes it strong.
  The conclusion is fairly weak it suggests only
  that smoking contributes to getting lung cancer,
  not that its the only cause - the evidence of
  a pattern of correlation over many years
  hundreds of thousands of people provides strong
  support for this weak conclusion.

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CT10f UNIT 2 SECTION 4Evaluating Argument

• When asked about weaknesses in the use of
  evidence, you need to explain why there is a
  problem with the way the author is using the
  evidence to support their reasoning.
• When asked about strength in the use of evidence,
  you need to show that the evidence is precisely
  relevant to the reason or conclusion it is
  supporting, and that it does support that reason
  or conclusion.

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CT10g UNIT 2 SECTION 4Evaluating Argument

• THE MEDIAN
• As we learnt in Unit 1, the mean is a good way to
  work out the average. However, there are two
  other common ways.
• Using the previous example of students percentage
  marks, we can find the median mark by putting the
  percentages and taking the middle value.
• Finally the average could be found by
  identifying the mode. This is the value in the
  set of percentages that occurs most often.
• Starting from the same set of data but by using
  different methods to calculate the average
  produces very different figures.

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CT10h UNIT 2 SECTION 4Evaluating Argument

• THE USE OF AVERAGES IN EVIDENCE
• We need to remember that an average figure does
  not apply to everyone when we evaluate how
  averages are being used as evidence to support
  reasoning in C.T. It is not representative of
  everyone in the group.
• A wedding is a very important day for a couple
  their family. However, the average spend on a
  wedding day is now a whopping 20,000, so it is
  clear that things have got out of hand. New
  couples need every penny for mortgages setting
  up home, not to mention the costs of bringing up
  children. This shows that the people who can
  least afford it are spending excessive money on
  weddings
• The above example shows how this average sum of
  20000 distorts the picture. It could be a few
  celebrities spend millions on weddings so the
  average rises. The average is not very
  informative.

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CT10i UNIT 2 SECTION 4Evaluating Argument

• You should approach evidence that is displayed
  visually (i.e. in a chart, table or a graph) in
  exactly the same way as you would evaluate any
  other piece of evidence. Ask yourself the same
  sorts of questions
• 1/ Is this evidence precisely relevant to the R
  or C it is supporting?
• 2/ Is this evidence sufficient to support the R
  or C?
• 3/ Are there any alternative conclusions that
  could be supported by this evidence?

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CT10j UNIT 2 SECTION 4Evaluating Argument

• Here are some questions you need to ask yourself
  when considering whether evidence is relevant to
  the R or C it supports.
• 1/ Does the evidence refer to one year, where
  this may not be representative of a trend or a
  reliable guide to past or future?
• 2/ If the evidence refers to an average, is this
  statistic being used (incorrectly) in a way which
  suggests it is representative of the whole group?
• 3/ Does it refer to the same group of people or
  subject as the reason it is meant to be
  supporting?
• 4/ Does it refer to the same timescale as the
  reason?

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CT10k UNIT 2 SECTION 4Evaluating Argument

• ADDITIONAL EVIDENCE TO STRENGTHEN OR WEAKEN AN
  ARGUMENT
• Some multiple choice questions may ask you to
  identify which piece of evidence, if true, would
  most strengthen or weaken an argument.
• If a piece of evidence supports one of the
  reasons or the reasoning, then it strengthens the
  argument. If it would counter a reason or show it
  to be wrong, or if a piece of evidence would
  support an opposing conclusion, then it would
  weaken an argument.
• Once you have considered this, you need to
  consider whether the evidence is precisely
  focused relevant to the conclusion. One of the
  possible answers in a multiple choice question
  may seem to work well, but on closer examination
  may be focused on a different conclusion.

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CT10l UNIT 2 SECTION 4Evaluating Argument

• EVALUATING THE USE OF EXAMPLES
• As well as using evidence, authors often use
  examples to illustrate their reasoning. Examples
  do not support an argument in the same way as
  evidence supports reasons or reasons support
  conclusions. They do not provide logical grounds
  for us to accept a reason or conclusion, but give
  a specific situation in which the reason holds.
• 1/ Is the example illustrating the argument or is
  it being used to support a general conclusion?
• 2/ Is the example precisely the same as the
  situation being talked about?
• 3/ Is the specific example typical or
  representative of the group being talked about?

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CT10m UNIT 2 SECTION 4Evaluating Argument

• When asked about weakness of the use of an
  example, you need to explain whey there is a
  problem with the way the author is using the
  example to support their reasoning.
• When asked about the strength in the use of an
  example, you need to explain how this particular
  example lends good support to the reasoning.

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CT10n UNIT 2 SECTION 4Evaluating Argument

• OFFERING ALTERNATIVE EXPLANATIONS
• Authors also often use explanations to support
  their reasoning. These explanations often affect
  the strength of support for the conclusion. If an
  author has used an explanation which is clearly
  wrong or implausible, this will weaken the
  support for their conclusion. You will need to
  identify such weaknesses offer plausible
  alternative explanations.
• There has been a rise in the number of cases of
  measles in the UK since 1998. This can be
  explained by bugs which are resistant to
  antibiotics. So we need to work hard on
  developing new drugs to combat measles.
• In the above example the authors explanation
  does not work as measles is a virus which does
  not respond to antibiotics. A more plausible
  explanation for the rise in measles would be the
  poor take-up of the MMR vaccine because of fears
  of autism.