Use both a linear and quadratic model to explore trends in the de-seasonalized data from Problem 15.40. Which model seems to produce a better fit of the data?

Industrial Machinery and
Time Period ........ Equipment Shipments
1st quarter (year 1) ...... 54.019
2nd quarter ....... 56.495
3rd quarter ....... 50.169
4th quarter ........ 52.891
1st quarter (year 2) .... 51.915
2nd quarter ........ 55.101
3rd quarter ....... 53.419
4th quarter ....... 57.236
1st quarter (year 3) .... 57.063
2nd quarter ....... 62.488
3rd quarter ........ 60.373
4th quarter ....... 63.334
1st quarter (year 4) .... 62.723
2nd quarter ........ 68.380
3rd quarter ....... 63.256
4th quarter ........ 66.446
1st quarter (year 5) ..... 65.445
2nd quarter ....... 68.380
3rd quarter ....... 63.256
4th quarter ....... 66.446
1st quarter (year 5) .... 65.445
2nd quarter ....... 68.011
3rd quarter ....... 63.245
4th quarter ........ 66.872
1st quarter (year 6) .... 59.714
2nd quarter ....... 63.590
3rd quarter ....... 58.088
4th quarter ........ 61.443