Given in the table is the past 8 years demand for the cell phones. Use the records of 2010-2014 to build your model and then estimate the data of 2015 -2017 based on the model you have developed. Calculate the MAD for your forecast of 2015-2017.

1. (25%) What will be the MAD by using moving average with three periods? 2. (25%) What will be the MAD by using moving average with three periods and seasonality? 3. (25%) What will be the MAD by using exponential smoothing (set initial forecast = 30)? 4. (25%) What will be the MAD by using exponential smoothing with seasonality (set initial forecast = 30)? 5. Develop you model by all means to predict the data for years 2015-2017 and show your results of MAD (for years 2015 -2017). The team with the least MAD and the second least will receive 10 and 5 bonus points, respectively.

Year Quarter Sales (in millions) 2010 1 30.1 2010 2 35.2 2010 3 49.8 2010 4 38.4 2011 1 32.1 2011 2 39.7 2011 3 56.8 2011 4 41.2 2012 1 35.3 2012 2 43.7 2012 3 60.5 2012 4 43.4 2013 1 37.9 2013 2 53.1 2013 3 67.5 2013 4 49.7 2014 1 41.6 2014 2 61.4 2014 3 77.3 2014 4 55.7 2015 1 43.8 2015 2 71.5 2015 3 84.0 2015 4 63.2 2016 1 52.2 2016 2 78.7 2016 3 97.4 2016 4 73.6 2017 1 57.4 2017 2 87.5 2017 3 107.1 2017 4 82.9