x.hat : the least sqaure estimate of the missing observation.
SSE.x.hat : Sum of Squares of Error of x.hat.
x.double.hat : the least square estimate of the missing observation under the null hypothesis , H0.
SSE.x.double.hat : Sum of Squares of Error of x.double.hat.
F.stat : Observed value of the Test Statistic.
F.crit.value : Critical value of the Test Statistic.