Find and identify the four seasonal factors for quarters 1, 2, 3, and 4.

International Machinery, Inc., produces a tractor and wishes to use quarterly tractor sales data observed in the last four years to predict quarterly tractor sales next year. The following MegaStat output gives the tractor sales data and the estimates of the seasonal factors and trend line for the data:

Transcribed Image Text:

Centered Sales, y Deseasonalized Ratio to Seasonal Moving Average Sales, y Indexes Year Quarter CMA 293 1.191 245.9 392 257.7 2 1 2 1.521 221 275.0 3 275.125 0.803 0.804 0.484 4 4 147 302.000 0.487 303.9 1.191 2 388 325.250 1.193 325.7 6. 2 512 338.125 1.514 1.521 336.6 2 3 287 354.125 0.810 0.804 357.1 381.500 380.4 8. 4 184 0.482 0.484 3 1 479 405.000 1.183 1.191 402.0 640 10 3 2 417.375 1.533 1.521 420.7 0.804 11 3 3 347 435.000 0.798 431.8 223 12 3 4 462.125 0.483 0.484 461.0 1.191 13 4 581 484.375 1.199 487.7 755 14 4 497.625 1.517 1.521 496.3 15 4 3 410 0.804 510.2 16 4 4 266 0.484 549.9 800 y = 19.95x + 220.54 700 R? = 0.9965 600 500 400 300 200 100 4 12 16 Quarter Sales, y Deseasonalized Linear (Deseasonalized) Sales, y