(a) The Marino Company in Ventura County, southem California sells swimming pool equipment. The sales for swimming pool motors in southern California over the last 12 months is given in Table Q4(a). Forecast the demand from March to December of the current year using the following forecasting models. Use excel for the tabulation. (i) Three-month simple moving average (i) Three-month weighted moving average. Use 0.7,0.2, and 0.1 for the weights, with 0.7 for the most recent period, and 0.1 for the oldest period. (ii) Simple linear regression; (iv) Determine the MAD, and SE for all the models, and choose which model is most appropriate. Table Q4(a) Marino Company Sales of Swimming pool motors Month Quantity (units) January 11,959 February 14,664 March 16,434 April 10,070 May 15,652 June 17,465 July 11,844 August 14,963 September 17,744 October 12,080 November 14,063 December 16,445 (b) Oman Steel Company is currently having five jobs to be completed in details of which is given in Table Q4(b). Using the following priority rules determine the order in which the jobs given in Table Q4(b) should be processed using the following rules; (i) Critical ratio (ii) Least amount of Slack per operation (ii) Johnson's rule Table Q4(b) Jobs (in the order they Days until due date Remaining processing time (days) arrived Drilling 4 R S T 9 5 7 6 Cutting 1 3 3 5 3 2 4 3 V (a) The Marino Company in Ventura County, southem California sells swimming pool equipment. The sales for swimming pool motors in southern California over the last 12 months is given in Table Q4(a). Forecast the demand from March to December of the current year using the following forecasting models. Use excel for the tabulation. (i) Three-month simple moving average (i) Three-month weighted moving average. Use 0.7,0.2, and 0.1 for the weights, with 0.7 for the most recent period, and 0.1 for the oldest period. (ii) Simple linear regression; (iv) Determine the MAD, and SE for all the models, and choose which model is most appropriate. Table Q4(a) Marino Company Sales of Swimming pool motors Month Quantity (units) January 11,959 February 14,664 March 16,434 April 10,070 May 15,652 June 17,465 July 11,844 August 14,963 September 17,744 October 12,080 November 14,063 December 16,445 (b) Oman Steel Company is currently having five jobs to be completed in details of which is given in Table Q4(b). Using the following priority rules determine the order in which the jobs given in Table Q4(b) should be processed using the following rules; (i) Critical ratio (ii) Least amount of Slack per operation (ii) Johnson's rule Table Q4(b) Jobs (in the order they Days until due date Remaining processing time (days) arrived Drilling 4 R S T 9 5 7 6 Cutting 1 3 3 5 3 2 4 3 V
