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Forecasting

Question 3

Multiplicative backwards

In a time series analysis using the multiplicative model, at a certain time actual,
trend, seasonal and cyclical values are 196.35, 150, 1.1 and 0.85 respectively.
Calculate the value of the residual element.

Y = T × S × C × R

196.35 = 150 × 1.1 × 0.85 × R

R = 196.35/(150 × 1.1 × 0.85) = 1.4

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