Pbiet cog thuc Wbquan va Iw

Ptich

(1) la so bquan dieu hoa gia dquyen dung de tinh nsld bquan of cong nhan trong dn khi biet tong san luong of dn o cac thoi ki(WiTi)va muc nsld tug thoi ki(Wi)

(2) la cthuc co dag so bquan dieu hoa gia quyen dung de tih chi so chung ve nsld of cn trong dn khi biet tong gia tri sx o ki bcao (WiTi) va chi so ca the ve nsld of cnhan (iw)

giong nhau

-deu co dag ct of so bquan dieu hoa gia quyen dang tong quat -X =(MMi)/(MMi/Xi)

-deu sdung de ngcuu nsld trong mqh voi tog so cog nhan

-quyen so deu la tog gtri sx Go

Khac

1/bchat

1 neu ken muc di nskd bquan dai dien of cn trong dn o 1 thki o 1 thoi ki nao do khi biet luong bien Wi va tich of luong bien voi tan so WiTi

2 neu lens u bdong of nsld bquan of cnhna toan dn khi so sah ki bcao voi ki goc khi biet gia trin sx ki baco (WiTi)va chi so ca the ve nsld (iw)

2/ndung

1tih nsld bq 1 cn trong dn o 1 thoi ki nao do

2 tih chi so ve nsld bquan 1 cn trog dn

3/y nghia

1 .anbag cac muc nsld of cn

.dai dien chung cho nsld cn toan dn trogn 1 thoi kin hat dinh nen co the dung de so sah nsld of cn o cac thoi ki khac nhau,tu do giup danh gia chat luong hoat dong of dn vat ay nhe cn

2 .neu lens u bdong ve nsld of cn

.chi r anh nhto anh huong den su bdong do

.neu su anh huong of sub dong dvoi chi tieu tog gtrisx

4/ap dung

1.cho tog the dong chat

.khi o du so lieu de tinh nhu cthuc bquan cong

2.cho tog the o,co dong chat

.khi o du so lieu de tinh nhu cthuc chi so lien hop

5/dvi

1.dvi kep

2.dvi lan,%

6/quyen so

1.la tog gtri sx o 1 thki bki WiTi

2 la tog gtri sx o ki bao cao