The main concern of this investigation involves the concept of “the probability of reversal.” That is, the determination of the conditional probability ofnot rejectingthe null-hypothesis,H0, if all the data (nfixed) are available, given thatH0isrejectedby the test of significance based on incomplete data (Type 1). Or, on the other hand, the conditional probability ofrejecting H0if all the data are available, given thatH0isnot rejectedby the test of significance based on incomplete data (Type 2). Therefore, “the probability of reversal” indicates the degree of stability in the statistical inference procedure when the originally designed experiment is disrupted by loss of observations.