Enrollment in a particular class for the last four semesters
has been 120, 126, 110,
and 130 ( listed from oldest to most recent ).
Suppose a one-semester moving
average was used to forecast enrollment ( this
is sometimes referred to as a naïve
forecast ). Thus, the forecast for the second
semester would be 120, for the third
semester it would be 126, and for the last
semester it would be 110. What would
the MSE be for this situation?