In addition to being reliable, evidence must also be valid.
It should be accurate and relevant to the argument or the theory it is supposed to support.
To assess the validity of the evidence, you need to evaluate the information and its analysis:
how the evidence has been interpreted.
You should ask, is the evidence accurate? Is the evidence relevant or out of context? Is the
evidence a representative example?
Let’s look at simple arguments supported by simple evidence
Here the argument is ‘France is a rainy country. My aunt in Paris says it rains 360 days of the
year. All the supermarkets sell umbrellas! I visited my aunt last year and it rained the entire
weekend I was there.’
Let’s take this in steps. In the first instance the evidence given to support the argument is
inaccurate, it almost certainly doesn’t rain 360 days per year – if you were to look at
accurate records of rainfall in France over the past 100 years, the average value is about 100
days per year.
In the second instance, the evidence ‘all supermarket sell umbrellas’ is irrelevant to the
argument. Supermarkets would sell umbrellas regardless of how rainy it was in France.
And finally, ‘I visited my auntie last year and it rained for the whole weekend’ this evidence
is not representative to support the argument.