128


Table 4.8


Prediction Accuracy of Equation 4.18--Error
Distribution as a Function of t
 1


ti Number of Cases with Percent Error Within
(in.) > 60 50-60 40-50 30-40 20-30 15-20 < 15


1.5 2 9 12 18 10 5 24

3.0 3 9 9 7 19 10 23

4.5 0 0 7 10 21 9 33

6.0 0 0 0 1 8 4 67

8.0 0 0 0 3 27 20 30


Total 5 18 28 39 85 48 177