model. The exponential smoothing model $is$ common $in$ practice. For instance, the basic exponential smoothing model for forecasting sales $is$

hat$(y{)}_{t+1}=y_t+(1-)hat(y{)}_t$

where

hat$(y{)}_{t+1}=$ forecast $of$ sales for period $t+1$

$y_t=$ actual value $of$ sales for period $t$

hat$(y{)}_t=$ forecast $of$ sales for period $t$

$=$ smoothing constant $0a1$

the unrounded values.$=0\mathrm{.}3$