E270 Homework

Emily Knapp

E270

Homework 2

1/29/13

1) A scatter diagram shows that the relationship between Total Gross Sales and Opening Gross Sales as upward sloping. This means that the 2 variables have a positive relationship.

2) The sample study of the movie industry shows us the mean (average) of 2 variables: The Total Gross Sales (33.04) and Weeks in the Top 60 (8.68). The sample also shows us the 1st Quartile, or 25%, of the 2 variables. For the Total Gross Sales, at least 25% of the observations are less than or equal to 0.39 and at least 75% of the observations are greater than or equal to .39. For Weeks in the Top 60, at least 25% of the observations are less than or equal to 3, and at least 75% of the observations are greater than or equal to 3. The range is the largest observation minus the smallest. For the Total Gross Sales, there is a range of 380.15 between the values, and for the Weeks in the Top 60, there is a range of 26 between the values. Standard Deviation is a measure of variability. For Total Gross Sales, the standard deviation is 63.16469269 and 6.389511608 for Weeks in the Top 60. Coefficient of Variation indicates how large the standard deviation is relative to its mean and is usually expressed as a percentage. The Coefficient of Variation is 191.1856891 for the Total Gross Sales and 73.6118849 for Weeks in the Top 60. With these values, we can see that the Total Gross Sales seem to vary more than the Weeks in the Top 60.