# Can Standardized unexpected earnings be considered a Z-score

According to this wikipedia: http://en.wikipedia.org/wiki/Earnings_surprise, the SUE score is a "standardized" difference between reported earnings and expected earnings. Therefore, can the SUE score be interpreted as a Z-score assuming that the underlying earnings surprise data is normally distributed?

No, because the $\sigma$ is estimated, and therefore SUE may be a t-score, but certainly not a z-score.