Lesson

We've already learnt about the range, which is a measure of spread in a data set. Once we are able to calculate the range in a data set, we can start to compare and make judgments about different data sets and potentially spot any outliers.

Now let's compare the spread of some data sets and graphs.

Look at the data sets below. Which data set has the largest range?

$101,105,118,129,136$101,105,118,129,136

A$19,23,25,28,29$19,23,25,28,29

B$22,25,43,64$22,25,43,64

C$104,107,113,120,125$104,107,113,120,125

D$101,105,118,129,136$101,105,118,129,136

A$19,23,25,28,29$19,23,25,28,29

B$22,25,43,64$22,25,43,64

C$104,107,113,120,125$104,107,113,120,125

D

Do the dot plots shown have the same range?

Yes

ANo

BYes

ANo

B

Plan and conduct investigations using the statistical enquiry cycle: A justifying the variables and measures used B managing sources of variation, including through the use of random sampling C identifying and communicating features in context (trends, relationships between variables, and differences within and between distributions), using multiple displays D making informal inferences about populations from sample data E justifying findings, using displays and measures.

Investigate a given multivariate data set using the statistical enquiry cycle