Dq27

Time 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?(1) What are the primary usages for time series modeling? What tools do we have to display the concept visually?(2) What are the limitations of time series modeling? How do we mitigate the limitations?(3) What are some of the ways your organization uses time series modeling? Provide real-time examples.(4) How do your view Statistics and Data Analytics differently than you did at the beginning of this course?