Introduction to Scatterplots and Correlation

The scatter plot shows the number of absences in a week for classes of different sizes.  Trevor concluded that there is a positive correlation.  Which statement best describes why Trevor's conclusion was incorrect.

• The largest class does not have the most absences.

• The smallest class does not have the least number of absences.

• The data show no relationship between class size and number of absences.

• The data show a negative relationship between class size and number of absences.

This scatter plot shows the average traffic volume and average vehicle speed on a certain freeway for 50 days in 1999.  Which statement best describes this relationship.

• As traffic volume increases, vehicle speed increases.

• As traffic volume increases, vehicle speed decreases.

• As traffic volume increases, vehicle speed increases at first, then decreases.

• As traffic volume increases, vehicle speed decreases at first, then increases.

Ms. Ochoa recorded the age and shoe size of each student in her physical education class.  This graph shows her data.  Which of the following statements about the graph is true?

• The graph shows a positive trend.

• The graph shows a negative trend.

• The graph shows a constant trend.

• The graph shows no trend.

What type of correlation does the following scatterplot show?

• Positive

• Negative 

• None

Predict what the next point would be on the scatterplot.

• (30,100)

• (20,20)

• (10,0)

Predict what the next point would be on the scatterplot.

• (10,10)

• (12.5,12.5)

• (4.5,7)

What type of correlation does the following scatterplot show?

• Positive

• Negative

• None

What is the independent variable?

• Precipitation

• Cucumber Yield

• kg

What is the dependent variable?

• Sunglasses Sold

• Ice Cream Sales

• Independent

Which is the correct relationship for the following graph?

• The systolic blood pressure depends on the age.

• The age depends on the systolic blood pressure.

• The blood pressure and age don't coorelate.