Tutor’s Toolkit: Application of Number

Interpreting Information

I6	Make accurate observations

I6.1	Keeping a tally

Scope: 

Students need to be able to:
•	construct a tally chart [NOE],
•	keep a tally from observations [NOE].

What students need to know:

Sometimes we need to collect live data.
It is important to have a well organised data collection form.
The most common way to collect data is to use a tally chart.
You need three columns:

Category	Tally	Frequency	

The category column contains the things you are going to count. Make sure you have divided these up as far as you need to. 

For example, let’s imagine that you are doing a traffic survey and you choose to count bikes. When you go out, you realise that motorbikes and bicycles will all go in the category. You cannot separate them after the event.

The tally column is for you to fill in on your clipboard when you are out and about – it is easy and quick to do and easy to count up afterwards.

Make marks like this . 
Each fifth mark crosses out the previous 4 to make a bundle: 
The frequency column is for the totals. 
The bundles make counting up easy:        makes 17.

Here’s a completed tally chart:

Category	Tally	Frequency	
Cars	      	17	
Buses	    	10	
Motor Bikes	  	8	
Bicycles		4	
Lorries	    	11