Algebra 1Algebra 1Algebra 1Algebra 1““Scatter Plots” and “Lines of Fit”Scatter Plots” and “Lines of Fit”

Scatter Plots & Lines of Fit• The points of a set of

real world data do not always lie on a line

• Sometimes you can draw a line that is close to all the points

• This graph represents the relationship between the year (x) and the number of Whooping cranes (y)

Scatter Plots:• Two sets of data plotted as

ordered pairs (Bivariate)• Here the 2 sets of data are:

Years (x) &

# of Whooping Cranes (y)• Scatter Plots are used to

investigate patterns in data

Analyzing Data :

• If the scatter plot is linear you can draw a line to summarize the data.

• This helps you to identify trends in the data.

• Also helps you identify the type of correlation.

• The year positively correlates to the number of Whooping Cranes.

Correlation:

• .

Correlation is like Slope• As the years progressed

(increased) the number of Whooping Crane grew (increased).

• This scatter plot shows a positive correlation in the data.

• Look at the Line of Fit and notice the positive slope

Is there a correlation?

Is there a correlation?

What (if any) is the correlation?

Exam the table. Determine what correlation, if any, exists in the data.

Sometimes math can be a little bit confusing

(photo from Poughkeepsie NY)

Okay Then, your turn

#1)

• Is there a correlation?

• What is it?

• What does it mean?

• TAKE A CHANCE Write an equation of the line of fit

#2)

• Is there a correlation?

• What is it?

• What does it mean?

• TAKE A CHANCE Write an equation of the line of fit

What (if any) is the correlation?

#3)

• Is there a correlation?

• What is it?

• What does it mean?

• TAKE A CHANCE Write an equation of the line of fit

What (if any) is the correlation?

Question Time

RAISE YOUR HAND if you

have any questions

about today’s lesson

Assignment:

Supplemental Handout