A well-known saying tells us that "there are lies, big lies and statistics". This is because statistics often do not represent the whole picture. For example: Some statistics, such as the average, show us the central tendency that characterizes a set of data. Imagine you have 3 tests, in Math, Physics and Art. You scored 100 for each test, so your average grade is 100. However, you then get 60 for your English test, and look what happens to your average: It goes down from 100 to 90, even though you got 100 for 3 out of your 4 tests. This is because the average can be strongly influenced by just a few numbers that are different from the rest of the set.
Read the paragraph and answer the question below.
Lies, Big Lies and Statistics
“Zebra crossings” are white stripes on a black road and are designed to help people to walk safely across busy roads. These stripes tell drivers to slow down and stop if people want to cross the road. However, statistics show that many accidents occur at “zebra crossings”. Does this mean that zebra crossings cause road accidents? No! This simply means that many more people cross the road at a zebra crossing, so the chances of people getting hit by a car at a zebra crossing are much greater than at other places on the road.
What is the main message of this exercise? Choose 2 correct answers.
