1 Collecting data

In the introduction we mentioned the different ways you can display information – for example, in tables, diagrams, charts or graphs. Before you can create any of these, however, you need to collect the information to put in them.

One way of collecting information is through a survey. Have you ever been stopped in the street by someone doing a survey, or filled one in online?

You’ll often see surveys by YouGov [Tip: hold Ctrl and click a link to open it in a new tab. (Hide tip)] , which is one example of a market research and data company, referred to on TV news programmes or in newspapers. YouGov commissions surveys on various topics, including the following (which you may want to open in a new window or tab):

• the public’s voting intention if there was a General Election held tomorrow

• the next actor to play James Bond

• how often we check our mobile phones

• people’s preference for dealing with climate change.

Note from these examples how survey results can be presented in different ways.

A survey is a method of collecting data. But once you’ve collected the data, it needs to be organised and displayed in a way that’s easy to understand.

This is something that’s straightforward to do with discrete data – that is, data made up of things that are separate and can be counted. For example:

• the number of people on a bus

• the number of cars in a car park

• the number of leaves on a tree.

A tally chart is a useful way of collecting information. A tally chart consists of a series of tallies. It works like this:

• For each thing, or unit, that you count – each person on a bus, each car in a car park, each leaf on a tree, or whatever – you make a tally mark like this:

  

• When you count up to five units, you ‘cross out’ the other four tally marks like this:

  

• You then continue to count units in groups of fives, as follows:

  = 4

  = 5

  = 6

  = 10

Now try the following activity. Remember to check your answers once you have completed the questions.

Example: Using a tally chart

You can use tally charts to record data when you carry out surveys and collect data.

Have you ever seen people at the side of a road doing a traffic survey? They could be recording the number of people in each car, and at the end of the survey they could add up the tallies and record the totals. Their tally chart would look something like this:

Number of people in car	Number of cars	Total number of cars
1		4
2		3
3		1
4		2
5+		1

So why use tally charts? It’s because they’re a quick and simple way of recording data.

Now try the following activities. Remember to check your answers once you have completed the questions.

Activity 2: Creating a tally chart

Twenty people were asked in a survey how many people lived in their house. These were the answers:

2	3	1	4	3
2	3	2	1	2
1	3	4	2	2
3	1	3	2	2

Use the information in the table above to create your own tally chart of how many people live in a house. Your tally chart should be arranged as follows:

Number of people in the house	Number of responses

Answer

Number of people in the house	Number of responses
1
2
3
4

Activity 3: Creating a tally chart

The following information is a record of the colours of cars in a car park one lunchtime:

red	yellow	red	blue	white
blue	black	white	red	green
red	white	green	black	blue
white	blue	red	red	black

Draw a tally chart to present the data.

Answer

Your table should look like this:

Number of cars with certain colours in a car park one lunchtime

Colour of car	Number of cars	Total
Black		3
Blue		4
Green		2
Red		6
White		4
Yellow		1

Notice how the tally chart has a title. It is important to give every table, graph or chart you produce an overall title.