Statistics

Statistics is all about dealing with information which someone has collected or recorded.  For instance, you could conduct a statistical survey by asking people at a local shopping centre who they were going to vote for in an upcoming election.  

There are several different stages when you are working with statistics.  We can show what these stages are by working through an example statistical problem.

Sandra is a reporter for the local newspaper, and she wants to get an idea of how each political party will go in the election.  She wants to write an article about what the current attitude is amongst the people in her area.  There are four candidates in this election who people can vote for:

Deciding what data to collect and how to collect it

Sandra first has to decide what information she’s going to collect, and how she’s going to get it.  A lot of surveys involve getting people to go out into public areas and ask people questions.  She decides she will go out and get the information herself.  But what information is she going to collect?

Well, one way she could do it is by just asking people who they are going to vote for in the upcoming election.  This would be very simple – each person would just have to say one of the four names – Bob, Jane, Sally or Tom.  Sandra decides to go with this approach – simple is often good.

How is she going to keep track of how many people have chosen each person?  She has to have some way of recording the data she collects.

Recording data

So Sandra’s out at her local shopping centre, with a clipboard and pen, and is asking people who they are going to vote for.  One person says Bob.  Another says Sally.  How is Sandra going to record this information?

One way she could record it is in a table, using a tally to count the number of votes for each person.  The table could be set up something like this:

Candidate	Tally of votes	Total
Bob
Jane
Sally
Tom

Now how is Sandra going to record the information in this table?  Well, every time she gets a vote for a candidate, she needs to put a mark in the tally box for that person.  So say she’s been surveying for 15 minutes, and she’s collected 23 votes for Bob, 17 for Jane, 13 for Sally and 5 for Tom.  Her table would look something like this:

Candidate	Tally of votes	Total
Bob
Jane
Sally
Tom

Sandra suddenly remembers that she has to be back at work, so she decides to finish the survey then and there.  She needs to fill in the totals column on the right side of the table by adding up the number of tallies for each candidate.

Candidate	Tally of votes	Total
Bob		23
Jane		17
Sally		13
Tom		5