Suppose the sales for ABC Corp. are shown in the table below.

a$)$ Use linear regression method to forecast the demand for Quarter $1$ of Year $4.$

$($Note that Year $2,$ Quarter $1$ should be changed to Quarter $5$; Year $2,$ Quarter $2$ should be changed to Quarter $6,$ and so on$.)$

b$)$ Forecast the sales for each of the four quarters for Year $4$ using the seasonality adjustment method discussed in class.

$\backslash$table$[[$Year$,$Quarter,Sales $($millions of units$)],[1,1,4\mathrm{.}5],[,2,3\mathrm{.}9],[,3,5\mathrm{.}5],[,4,6\mathrm{.}4],[2,1,4\mathrm{.}8],[,2,4\mathrm{.}1],[,3,6],[,4,6\mathrm{.}5],[3,1,5\mathrm{.}8],[,2,5\mathrm{.}2],[,3,6\mathrm{.}8],[,4,7\mathrm{.}4]]$Forecasting $($MAN $325$: Goh$)$

Tammy Dough, manager of Dough's Pizza, must forecast weekly demand for these special pizzas, Polish

Prize Pizza, so that she can order the correct amount of pizza shells weekly. Recently, the demands are as

follows:

a$)$ Forecast the demand for Polish Prize Pizza for Weeks $4,5$ and $6,$ using the $3$ period moving average

method.

$($b$)$ Forecast the demand for Weeks $4,5$ and $6,$ using weights of $0\mathrm{.}5,0\mathrm{.}3,0\mathrm{.}2$ for the most recent, next recent,

and most distant data, respectively.

c$)$ Assume that the forecast for Week $1$ is $550.$ Forecast the demand for Week $2$ through Week $6$ using the

exponential smoothing method with $=0\mathrm{.}3.$

d$)$ Now, forecast the demand for Weeks $2$ through $6$ using the exponential smoothing method with $=0\mathrm{.}8.$

How does it compare to that in part $($c$)?$

Suppose the sales for ABC Corp. are shown in the table below.

a$)$ Use linear regression method to forecast the demand for Quarter $1$ of Year $4.$

$($Note that Year $2,$ Quarter $1$ should be changed to Quarter $5$; Year $2,$ Quarter $2$ should be changed to

Quarter $6,$ and so on$.)$

b$)$ Forecast the sales for each of the four quarters for Year $4$ using the seasonality adjustment method

discussed in class.

A forecasting model has produced the following forecasts:

a$)$ Fill in the blanks above

b$)$ Calculate the mean absolute deviation $($MAD$)$ at the end of April.

c$)$ Calculate the average error at the end of April.

d$)$ Calculate the tracking signal at the end of April.