Q2.The data , in the nextTable, representHistorical Monthly Usage of a materialbythe AZX Company. Use minitab to :

a)Plot the data and check for stationarity using autocorrelation and Partial Autocorrelation.

b)Find an ARIMA model using the Box-Jenkins approach .

c)Forecast the monthly consumptionfor year 2007 using themodel identified in (b) .Plot the forecastand the historical data and comment on the result

d)Do model checking using the ACF of residuals, residuals Histogram, Normality plot of Residuals , Residuals vs Fits. Comment on the results.

Show all minitab Output

Historical Monthly Usage of A material