Slide 2:
scatter plot – a graph used to determine whether there is a relationship between paired data. Positive Correlation Negative Correlation No Correlation
Slide 3:
EX Describe the correlation of the data graphed in the scatter plot. Hours of studying Test scores There is a positive correlation. As the hours of studying increased, the test scores tended to increase.
Slide 4:
EX Describe the correlation of the data graphed in the scatter plot. Hours of television watched Test scores There is a negative correlation. As the hours of watching television increased, the test scores tended to decrease.
Slide 5:
EX The table shows the largest vertical drops of nine roller coasters in the US and the number of years after 1988 that they were opened. Draw a scatter plot and determine if there is a correlation. Years After 1988 Vertical Drop (ft) • • • • • • • • •
Slide 6:
line of fit – a trend line that models data when there is a positive or negative correlation.
Steps to Draw a Line of Fit
1. Make a scatter plot.
2. Decide if there is a positive or negative correlation.
3. Draw a line that fits the data.
4. Write an equation using two points on the line.
Slide 7:
EX The table shows the calories and fat in selected fast-food meals. Fat (g) Calories (36, 633) (7, 260) y = mx + b (7, 260)