In: Statistics and Probability
The Wade Tract Preserve in Georgia is an old-growth forest of longleaf pines that has survived in a relatively undisturbed state for hundreds of years. One question of interest to foresters who study the area is “How do the sizes of longleaf pine trees in the northern and southern halves of the forest compare?” To find out, researchers took random samples of 30 trees from each half and measured the diameter at breast height (in centimeters). Here are the summary statistics:
n |
Mean |
Standard deviation |
|
Northern |
30 |
23.70 |
17.50 |
Southern |
30 |
34.53 |
14.26 |
Construct a 90% confidence interval for difference in the mean diameter at breast height between the southern and northern trees.