STATISTICS

QUESTION 3 [16 MARKS] The measures in the table below were used to determine accuracy of forecasts developed to estimate salary increases in an agricultural firm. Method 1 Method 2 Method 3 Method 4 Method 5 36 11.268 22.668 11.268 3.643 2.668 i-I 36 35.1 41.7 53.1 27.2 31.7 8.76 88.76 81.76 17.8 18.76 BEME A; 36 6.31 36.31 56.31 26.85 16.31 36 7.35 (e, - 2 ) 18.25 10.35 15.26 8.25 (a) Which of the measures of accuracy is impossible to calculate from the table above? Why? (2) (b) Identify methods that overforecast and those that underforecast. (4) (c) Calculate for Method 4 and Method 5, the (1) mean absolute deviation. (1i) standard error of prediction. (c) Explain from your analysis a better method between Methods 4 and 5