350 exam 1 fomula.docx - Simple Moving Average use given most recent periods Weighted moving average=SUMPRODUCT(A1:An \$F\$1:\$F\$n Simple exponential

# 350 exam 1 fomula.docx - Simple Moving Average use given...

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Simple Moving Average - use given most recent periods Weighted moving average=SUMPRODUCT(A1:An, \$F\$1:\$F\$n) Simple exponential smoothing with alpha= α = 0.1~0.9 Average n = α *actual demand(covers sold)+(1- α )*Average n -1 Forecast n =ROUND(Average n-1 , 0) Error=Forecast-Actual demand MAD 1 =ABS(Error 1 ) MAD n =\$ϕ*ABS(Error n )+(1-\$ϕ)MAD n-1 phi=ϕ BIAS 1 =Error 1 BIAS n =\$ϕ*Error n +(1-\$ϕ)*BIAS n-1 MSE 1 =Error 2 MSE n =\$ϕ*Error n 2 +(1-\$ϕ)*MSE n-1 COMBINED=MAD+ABS(BIAS)+MSE Best alpha produces lowest combined error MAD=9.66 on average, we are 9.66 off from the actual demand BIAS<0 Overall underforecast / BIAS>0 overforecast MAD 2 <MSE There should be some large errors. Trend 1 =(AVERAGE(Demand 4 :D 6 )-AVERAGE(D 1 :D 3 ))/3 Average 1 =AVERAGE(D 1 :D 3 )-Trend 1 Average n ==\$ α *D n +(1-\$ α )*(A n-1 +T