Forecasting Worldwide Monthly Unit Sales of Tractors: In developing supply chain operational plan for 2022, including supply, manufacturing, distribution, and sales operational planning, requires PLE to have accurate forecast of worldwide monthly unit sales of tractors. The worldwide sales data for the period January 2017 - December 2021 are compiled in the Dataworksheet. PLE Senior executives expects you to: (i) justify, select, and develop the most appropriate time series model(s); (ii) use the developed time series model to prepare worldwide monthly unit sales forecasts for tractor for the year 2022. In meeting the PLE senior executives expectations follow the Seven-Step approach presented in the Lecture 03 video presentation and PP slides to answer the following questions. In answering the questions, use the ASPE Software Platform to complete the required modeling and analyses efforts: 1 - Develop a time-series plot for tractor worldwide unit sales. 2 - Determine the time series patterns you observe in the time-series. 3 - Considering the patterns you observe in the time series, determine the most appropriate forecasting model choice(s) for tractor unit sales. You can have more than one appropriate forecasting model choice. [Hint: Consult Table .9.1 in the textbook, on page 294]. Justify your model choices. 4 - Let's assume that your justified forecasting model choices are Holt-Winters Additive Model and Holt-Winters Multiplicative Model. Using ASPE, develop both models. 5 - Considering the ASPE outputs for each forecasting model choice, analyze the accuracy of your model based on the error measurements. 6 - For each forecasting model choice, create a 95% Confidence Interval (CI) graph which includes forecasted sales, CI lower and upper values. 7 - Develop your conclusions for each 95% confidence interval (CI) graph. 8 - Compare the predictive quality of both forecasting model choices you developed and justify which forecasting model should be recommend to the PLE executives. 9 - Organize all your analysis results in a summary format for quick reference in completing the online Modeling andDataAnalysisQuiz3-1.

Worldwide Monthly Tractor Unit Sales: January 2017 - December 2021 Month Tractor Jan-17 1592 Feb-17 1711 Mar-17 1810 Apr-17 1867 May-17 1779 Jun-17 1740 Jul-17 1826 Aug-17 1695 Sep-17 1681 Oct-17 1663 Nov-17 1825 Dec-17 1720 Jan-18 1761 Feb-18 2035 Mar-18 2142 Apr-18 2340 May-18 2280 Jun-18 2271 Jul-18 2154 Aug-18 2146 Sep-18 2085 Oct-18 1970 Nov-18 1936 Dec-18 1850 Jan-19 2000 Feb-19 2324 Mar-19 2510 Apr-19 2672 May-19 2780 Jun-19 2813 Jul-19 2716 Aug-19 2581 Sep-19 2476 Oct-19 2317 Nov-19 2324 Dec-19 2080 Jan-20 2202 Feb-20 2540 Mar-20 2867 Apr-20 3348 May-20 3550 Jun-20 3432 Jul-20 3400 Aug-20 3261 Sep-20 3209 Oct-20 3132 Nov-20 3027 Dec-20 2777 Jan-21 2821 Feb-21 3209 Mar-21 3553 Apr-21 3820 May-21 4133 Jun-21 4476 Jul-21 4436 Aug-21 4256 Sep-21 4067 Oct-21 3890 Nov-21 3816 Dec-21 3717