Review
d
BLS
І
1968
ϋৎdуʔ֛ಂ০࿁ཀ̘ఱุપПഐ
؈
ආБᏨൖၾ൙Пd
Ԩਗ਼ᗫ൙П
Projection Evaluation
2
జѓ̊༱௶ਗ୕
ࠇ
˜జf
ၾ੬Ԉʘ൙П˙
މ༰ج
ʔΝٙ݊dৰə൙Пධͦཫ
࠽
ʘᆽ
ܓ
̮d͵Ͻඎ
Ցධͦഐʱৣʿᜊਗ˙Σٙཫۜሯd˸ɨ০࿁ཫ
࠽
eഐʱৣeᒈැ˙Σ
ഃ
3
ࠦΣԱҏႭՉ൙П˙
ج
j
(
ɓ
)
ཫ
࠽
൙П
˴
ࠅ
ፅඎཫ
࠽
ᕎྼყ
࠽
ٙ
ܓ
d൙П˙
ج
ɪdɦ̙ʱ
މ
ఊɓཫ
࠽
൙П
ʿཫ
࠽
൙Пfఊɓཫ
࠽
ʘ൙Пɪd͉Ӻમ͜ϵʱˢႬࢨ
Percent
error,
˸ɨᔊ၈
error
ĈdՉ
ࠇ
ၑ˙ό
މ
j
Չʕd
P
i
=
Бุāᔖุāԃй
i
ఱุɛᅰʘཫ
࠽
A
i
=
Бุāᔖุāԃй
i
ఱุɛᅰʘྼყ
࠽
ίཫ
࠽
ʘ൙Пɪd͉Ӻમ̻͜ѩഒ࿁ϵʱˢႬࢨ
Mean Absolue
Percentage Error,MAPE
d
MAPE
ࠇ
ၑɪɦ̙ʱ
މ
̋ᛆ
weighted
ʿ͊̋
ᛆ
unweighted
j
Չʕd
A
i
=
Бุāᔖุāԃй
i
ఱุɛᅰʘྼყ
࠽
P
i
=
Бุāᔖุāԃй
i
ఱุɛᅰʘཫ
࠽
W
i
=
Бุāᔖุāԃй
i
ఱุɛᅰ̕ᐼྼყఱุɛᅰʘˢଟ
n=
Бุāᔖุāԃйʘʱᗳ
ࡈ
ᅰ
2
ᗫజѓ̙ਞቡ˸ɨၣѧj
Error% = ×100
P
ᵢ−
A
ᵢ
−−−−
A
ᵢ
Weighted equation: MAPE =
×100
∑ ⁿ Wᵢ
︱ ︱
ᵢ
P
ᵢ−
A
ᵢ
−−−−
A
ᵢ
Unweighted equation: MAPE =
×100
∑
︱ ︱
P
ᵢ−
A
ᵢ
−−−−
A
ᵢ
1
−
n
58
