Algebra 3

Lesson 1.9

Objective:

SSBAT identify positive, negative or no correlation.

SSBAT calculate the line of best fit using a graphing calculator.

Standards: M11.E.4.2.1; M11.E.4.2.2

Scatter Plot

A graph in which 2 sets of data are plotted as ordered pairs on a coordinate grid

When the 2 sets of data have a pattern they are said to be correlated.

Positive Correlation

The y-value increases as the x-value increases

The graph will go in an uphill motion from left to right

Negative Correlation

As the x-value increases the y-value decreases

The graph will go in a down hill motion from left to right

No Correlation

There is no relationship between the x and y values

The points on the graph are just scattered

Complete Worksheet: 1.9 Scatterplots A

Line of Best Fit or Regression Line

Can be drawn when a scatterplot shows a positive or negative correlation

A straight line that best represents the data in a scatterplot

http://hotmath.com/hotmath_help/topics/line-of-best-fit/lineofbestfit-h-2.gif

http://crctlessons.com/images/line-of-best-fit.jpg

Examples of a Best Fit Line

Complete Worksheet: 1.9 Scatterplots B

Day 2

Linear Regression Calculator

Complete Worksheet 1.9