The data in the table below represents data from the lumber industry. The information listed approximates the number of board feet of lumber per tree in a forest for a given age.
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In order to evaluate and interpret the data, a scatterplot is formed for the above data.
The graph appears to be quadratic in form. Based on this information, a regression equation can be made to approximate the path of the curve.
.Using this equation, the estimated values based on the age of the tree are as follows:
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The scatterplot below depicts how the values, using prediction equation, follow the path of the original curve.
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The correlation coefficient for the tree data is .94135. Because this coefficient is so close to +1, there is a strong positive relationship between the age of the tree and the number of board feet that can be obtained from the tree. This was evident by the graphic display of the data.