Consider the following data. We want to monitor the forecasts.

Period..............Demand............Forecasts ......

1...................265....................-- ......

2...................261....................265 ......

3...................286....................261 ......

4...................297....................286 ......

5...................318....................297......

Calculate the UCL and LCL for the appropriate control chart? Calculate the cumulative error, MAD, and tracking signals.

Error of period 2:

Error of period 3:

Error of period 4:

Error of period 5:

Overal MSE:

UCL to monitor the magnitude of the errors:

LCL to monitor the magnitude of the errors:

Are the errors in control? Yes No

Cumulative error up to period 2:

Cumulative error up to period 3:

Cumulative error up to period 4:

Cumulative error up to period 5:

MAD up to period 2:

MAD up to period 3:

MAD up to period 4:

MAD up to period 5:

Tracking signal of period 2:

Tracking signal of period 3:

Tracking signal of period 4:

Tracking signal of period 5:

Based on your tracking signals, are the forecasts biased? Yes No