Use scatter plots to investigate and comment on relationships between two numerical variables (VCMSP352)
LO: To investigate and comment on scatter plots.
Know:
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How to create a scatter plot from given data.
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How to label a scatter plot graph with the x and y axis.
Understand:
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That scatter plots can be used to represent a relationship between two factors (variables).
Do:
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I can use scatter plots to investigate and comment on relationships between two numerical variables.
Elaborations
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using authentic data to construct scatter plots, make comparisons and draw conclusions
Visual Representations

Scatter Plots

Scatter plots are an easy way of organising data from two categories into 1 graph. A scatter plot is a graph designed to show a relationship between corresponding numbers from two sets of data measurements associated with a single object or event. For example, a graph about marks and the corresponding amount of study time.
Basically, it’s identifying data from 2 categories then placing a dot (point) on a co-ordinate/Cartesian plane at where the data points correspond.
Relationships in Scatter Plots

Sometimes we can draw a generalization from the data that we see in a scatter plot.
If the data points are moving (trending) towards the upper right then it can be considered to have a positive correlation. Both variables are increasing at a similar rate.
If the data points are moving (trending) towards the bottom right then the data can be considered to have a negative correlation. Both variables are decreasing at a similar rate.
If the data points don’t present a trend (all over the place) then the data can be considered to have no correlation.
Positive Correlation

This is an example of a positive correlation, as students spent more time studying, the student grades also improved.
Negative Correlation

This is an example of a negative correlation, as students spent more time training, the time it took to run 100m decreased.
No Correlation

This is an example of no correlation, the colours in a rainbow have no relationship to the shoe size.
Teaching Ideas
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compare two attributes or characteristics (e.g., height versus arm span), using a scatter plot, and determine whether or not the scatter plot suggests a relationship.
compare two attributes or characteristics (e.g., height versus arm span), using a scatter plot, and determine whether or not the scatter plot suggests a relationship.
Creating a Scatter Plot Videos
Correlation Videos
Practise Questions
My Maths 9
Exercise 8F pg. 395 Q. 10-12
My Maths 10/10A
Exercise 10E pg. 507 Q. 1-5