September – December 2023 Time Series Modeling
Business & Finance
Due Day 3Time series are particularly useful to track variables such as revenues, costs, and profits over time. Time series models help evaluate performance and make predictions. Consider the following and respond in a minimum of 175 words:Time series decomposition seeks to separate the time series (Y) into 4 components: trend (T), cycle (C), seasonal (S), and irregular (I). What is the difference between these components?The model can be additive or multiplicative.When we do use an additive model? When do we use a multiplicative model?The following list gives the gross federal debt(in millions of dollars) for the U.S. every 5 years from 1945 to 2000:Year Gross Federal Debt ($millions)1945 260,1231950 256,8531955 274,3661960 290,5251965 322,3181970 380,9211975 541,9251980 909,0501985 1,817,5211990 3,206,5641995 4,921,0052000 5,686,338Construct a scatter plot with this data. Do you observe a trend? If so, what type of trend do you observe?Use Excel to fit a linear trend and an exponential trend to the data. Display the models and their respective r^2.Interpret both models. Which model seems to be more appropriate? Why?