Statistical questions and statements

Your teacher says they are meeting two childhood friends this evening. One is 5 feet tall and the other is 6 feet tall. What is your guess as to each friend's gender?

You probably guessed that the 5-foot-tall person is a woman and the 6-foot-tall person is a man. There is a chance you are wrong — but experience tells us that 5-foot-tall men and 6-foot-tall women are rare, and that more often, men are taller than women.

That guess is a simple example of statistical thinking: reasoning from what usually happens, while knowing the answer is not certain.

We meet such claims constantly. 'I take about 15 minutes to cycle from school to home.' 'David spends about 7 hours daily in school.' 'The population of their village has reduced by about 100 in the last decade.' 'Jemimah's batting has been very consistent over the past year.'

These are statistical statements. Simply put, a statistical statement is a claim or summary about some phenomenon, expressed in terms of numerical values, proportions, probabilities or predictions.

A statistical question is one that can be answered by collecting data. 'How tall are Grade 7 students in our school?' is a statistical question: not all of them have the same height, but we can collect the data, analyse it and draw conclusions. 'Typically, are onions costlier in Yahapur or Wahapur?' is one too, because prices vary over time and only data can settle it.

Some questions are not statistical. 'Do you like reading?' has a single answer from one person, with nothing to collect and analyse. Test a few: how old are the dogs on this street; what fraction of your class likes walking up a hill; approximately how many bricks are in this wall; what was the rainfall pattern in Barmer last year. STATISTICS is the study of collecting, organising, analysing, interpreting and presenting data.