In any production process in which one or more workers are engaged in a variety of tasks, the total time spent in production varies as a function of the size of the workpool and the level of output of the various activities. In a large metropolitan department store, it is believed that the number of man-hours worked (y) per day by the clerical staff depends on the number of pieces of mail processed per day (x1) and the number of checks cashed per day (x2) . Data collected for n=20 working days were used to fit the model:
E(y)=β0+β1x1+β2x2
A printout for the analysis follows:
SOURCE MODEL ERROR Analysis of Variance DF 21719 SS 7089.065124541.7214211630.78654 MS 3544.53256267.16008 F VALUE 13.267 PROB > F 0.0003
ROOT MSE DEP MEAN C.V. 16.3450393.9268217.40188 R-SQUARE ADJ R-SQ 0.60950.5636
VARIABLE INTERCEPT X1 X2 PARAMETER DF 111 STANDARD ESTIMATE 114.420972−0.0071020.0372901.824 T FOR 0: ERROR 18.684857440.001713750.020439370.0857 PARAMETER =06.124−4.144 PROB >∣T∣0.00010.0007
OBS X1 7781 X2 644 Actual Value 74.707 Predict Value 83.175 Residual −8.468 Lower 95% CL Predict 47.224 Upper 95% CL Predict 119.126
Test to determine if there is a positive linear relationship between the number of man-hours worked, y , and the number of checks cashed per day, x2 . Use α=.05 .
Holding Cost
The expenses associated with storing unsold goods or materials, including warehousing, insurance, depreciation, and opportunity cost.
Shipping Cost
The expense incurred to transport goods from one location to another.
Factor Weighting Technique
A decision-making tool that assigns weights to various factors or criteria based on their importance, used to evaluate alternatives or make choices.
Subjectivity
The quality of being based on or influenced by personal feelings, tastes, or opinions rather than external facts or evidence.