Suppose your Time Series regression model has forecasted the next 6 months of sales . You feel your sales amounts will appear too sporadic and you feel a 3 - month moving average ( aka , Rolling Mean in Time Series ) would better depict your sales performance moving forward . Utilizing Gaussian distribution logic , you will need to present your " Mean of Sample Means " , as well as your " Standard Error " . You will be attempting to procure a business bank loan and you feel the banks will need to see less sporadic sales numbers for you to qualify . Please calculate the mean squared error ( MSE ) , as well as the standard deviation of these sample means ( standard error ) , utilizing the MSE , for your sales data . Note : I did say if you only calculated the bottom three sample mean values , that would be sufficient for calculating your mean of sample means , provided you calculated the correct " raw data " mean , and used that value to calculate your answers .

Month	Sales (in million)
1	6
2	2
3	4
4	11
5	9