Scatterplot Introduction

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.

John recorded the number of hours he spent exercising each week and his weight at the end of the week for several weeks. The scatterplot below shows his records. What can be inferred from the scatterplot?

• As the number of hours spent exercising increases, John's weight decreases.

• As the number of hours spent exercising increases, John's weight increases.

• There is no relationship between the number of hours spent exercising and John's weight.

Which graph best shows a positive correlation between the number of hours studied and the test scores?

• Graph A

• Graph B

• Graph C

• Graph D

What type of association does this graph have?

• positive

• negative

• none

• all of the above

What type of association does this graph have?

• positive 

• negative

• none

• all of the above

What type of correlation does this scatterplot display?

• Positive

• Negative

• No Correlation

What type of correlation does this scatterplot display?

• Positive

• Negative

• No Correlation

Mr. Thomas wanted to know if the amount of class time that he gave students to study affected their test scores.  What kind of relationship between class study time and test scores is shown on the scatter plot.

• No correlation

• Positive correlation

• Negative correlation

• Positive then negative correlation

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.