Apply Holt-Winters Double exponential smoothing (without seasonality) to forecast the values of sales X for periods 12 and 13, using α = 0.2 and β = 0.3. Assume 12 months of sales data, as shown in the table below:
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Alpha = 0.3
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Beta =
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0.4
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t
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Sales Xt
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t
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Tt
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t+ Tt
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1
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152
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2
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176
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3
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160
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4
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192
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5
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220
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6
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272
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7
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256
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8
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280
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9
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300
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10
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280
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11
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312
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12
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328
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