Comparing sets of data - BBC Bitesize (2024)

Key points

Comparing sets of data - BBC Bitesize (1)

An understanding of , , and is essential to be able to compare sets of data.
Data can be compared in two different ways:
1. By comparing an , such as the mean, median or mode. An average gives a typical value, so comparing averages shows whether one set of data is generally higher or lower than the other. The mean is the most common way to compare two sets of data, but the median or mode may be better if there is an in the data.
2. By comparing the . The range shows how spread out the data is, so comparing ranges shows whether one set of data is more than the other.

Comparing sets of data - BBC Bitesize (2)

Video

Watch the video to hear Steph, a sports coach, talk about why collecting and comparing data is useful and interesting for coaches, players and fans.

How to compare data sets

To compare two or more data sets, it is too complex to look at every value, especially if there are a large number of figures. It is easier to compare the data using one typical value to represent each data set, such as the , or . This helps to suggest which set of data is higher on average.
The is the difference between the lowest and highest values. It measures how varied the data is. If a set of data has a lower range, the values are closer together and so the data is more consistent.

Examples

Image gallerySkip image gallery

Slide 1 of 9, An image of two sets of data. Each set of data is made up of eight values. The first set of data is labelled, Farmer A, and has values, twenty one, comma, twenty three, comma, twenty five, comma, twenty six, comma, twenty six, comma, twenty nine, comma, twenty nine, comma, thirty seven. The second set of data is labelled, Farmer B, and has values, twenty three, comma, twenty four, comma, twenty six, comma, twenty seven, comma, twenty eight, comma, twenty nine, comma, thirty three, comma, thirty four., Two farmers grow 8 marrows. These are the lengths of the marrows in cm.

End of image gallery

Match the comparisons with the statements

Practise comparing data with this activity. Match the comparisons with the correct statement.

Question

Alex and Tia have completed eight spelling tests and their ordered results are below. Each student wants to argue they have performed better.

What average could each of them use to suggest they are better at spelling?
Could the range be used as evidence too?
Whose argument would be most convincing?

Comparing sets of data - BBC Bitesize (4)

Practise comparing sets of data

Quiz

Practise comparing sets of data with this quiz. You may need a pen and paper to help you.

Real-life maths

Comparing sets of data - BBC Bitesize (5)

Statistics and averages are often presented in the news, in documentaries or on social media.

Different averages can be used to support a particular point of view. Statistics may be carefully chosen for content in the media to make an argument or present a certain way of thinking to an audience.

By selecting a particular average to compare figures, it is possible to influence other people's opinions.

As a reader or viewer, a clear understanding of averages is helpful to spot when data may be presented in a way that is potentially misleading.

Comparing sets of data - BBC Bitesize (6)

Game - Divided Islands

Play the Divided Islands game! gamePlay the Divided Islands game!

Using your maths skills, help to build bridges and bring light back to the islands in this free game from BBC Bitesize.