Let the following set of data correspond to the saw sales of the company Stockonte SA$,$

Questions

Use the exponential smoothing method $($with values of $\backslash$alpha $=\{\mathrm{.}1,\mathrm{.}5,$and $\mathrm{.}9\}),$ to forecast all possible periods using the moving average of order $9$ as the initial forecast.

Forecast sales levels for each period using moving average of order $3,6$ and $9.$

Calculate, using linear regression, the sales forecast for all periods. $(15$ points$)$

What forecasting method do you suggest for this data set, if you base your decision on the MAD criterion?

If you use the PEMA criterion, do you maintain the decision of the previous answer? Comment.

year quarter t sales

$200011500$

$22350$

$33250$

$44400$

$200115450$

$26350$

$37200$

$48300$

$200219350$

$210200$

$311150$

$412400$

$2003113550$

$214350$

$315250$

$416550$

$2004117550$

$218400$

$319350$

$420600$

$2005121750$

$222500$

$323400$

$424650$

$2006125850$

$226600$

$327450$

$428700$