only generating 2,000 replicates can take about 10.46 days. However, using EEE the computational time in calculating power will be almost negligible. Though some situations exist in which the procedure is not useful, such situations are predictable and in those situations, EEE should typically not be used. For example, when the power of the available study is less than 10% and sample size for the planned study is 4 times larger than the available study power. In such extreme situations then, investigators should proceed with caution, if at all, with the use of the EEE approximation. However, one can still use EEE in these extreme situations, but EEE power will be very conservative. Yet in the vast majority of situations, EEE approximates power extremely accurately and can be used with confidence, provided the initial simulated power values taken as inputs are believed to be trustworthy and are derived from a sufficiently large number of simulation runs. EEE enjoys not only a sound theoretical asymptotic basis, but has now empirically been shown to work quite well across a great variety of genomic research situations.
