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dear sir can you help me with these two questions?
1.A product has a constant(flat)trend in its sales, and is subject to quarterly seasonal variations as follows:
Quarter Q1 Q2 Q3 Q4
Seasonal +50% +50% -50% -50%sales last quarter, Q2 were 240 units
Assuming a multiplicative model for the time series, predicted unit sales for the next quarter will be closet toA.80
B120
C160
D3202.In a time series analysis, using additive model, at a certain time, the following data is obtained.
Actual value 170
Trend 182
Seasonal Value -12.8The residual value at this point is
A-0.8
B0.8
C-24.8
D24.81) If the trend is constant, it would mean that if there were no seasonal variation then we would expect sales in the next quarter (Q3) to be 240.
However, there is a seasonal variation in Q3 of -50%, so the actual forecast for Q3 will be 240 – (50% x 240) = 120.2) Our forecast would the trend (182) adjusted by the seasonal variation ( -12.8) which would be 182-12.8 = 169.2
The actual figure is 170.
So the difference is 170 – 169.2 = +0.8
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