37
t
e. Deviasi Standar Galat ( Standard Deviation of Error )
1
n
2
SDE
n
1
t
1
et
f.
Nilai Tengah Deviasi Absolut ( Mean Absolut Deviation )
MAD =
1
|
X
n
t
X
|
Statistik Ketepatan Ramalan Relatif
a. Galat Persentase ( Percentage Error )
X
PE
t
F
x100
X
t
b. Nilai tengah Galat Persentase ( Mean Percentage Error )
1
n
MPE
n
t
1
PE
t
 |