[填空题]
The following table s/fvb.,/h) 5.yus;rk)uogrhx ag8 mmthows the average height, x,jni4) 8lc/ *2gqq pvct and the average trunk diameter, y, of eight species o2cpj/ qlgnvc i tq84*)f tree.
1. Find the range of the average heights for these eight species of tree, correct to two decimal places.
2. From the data from of these eight species of tree
1. calculate the Pearson's product-moment correlation coefficient, r ; ≈
2. describe the correlation between the average height and the average trunk diameter.
3. Write down the line of regression equation, y on x , in the form y=m x+c .
The average height of another tree species, Black Ash, is 15.2 $\mathrm{~m}$ .y =ax+b a = b =
4. Use your regression line to estimate the average trunk diameter of Black Ash.
The average diameter of Black Ash is found to be 0.445 $\mathrm{~m} $. ≈
5. Find the percentage error in your estimate in part (d).
The average height of another tree species, Alpine Ash, is 87.5 $\mathrm{~m}$ . ≈ %
6. State whether it is valid to use the regression line to estimate the average trunk diameter of Alpine Ash. Give a reason for your answer.
7. Complete the two empty rank columns in the table and state why the Spearman's rank correlation coefficient could be calculated by inspection.
