Enter a series of values to compute the sample skewness g1 from the third standardised central moment, judging left/right skew and symmetry of a distribution.
| Item | Formula / Note | Source / Standard |
|---|---|---|
| Population skewness | gamma1 = mu3 / sigma^3, where mu3 is the third central moment | ISO 3534-1:2006, Statistics - Vocabulary and symbols |
| Sample skewness (Fisher-Pearson) | g1 = m3 / m2^(3/2), with m2 and m3 the sample central moments | NIST/SEMATECH e-Handbook of Statistical Methods §1.3.5.11 |
| Adjusted sample skewness | G1 = g1 · sqrt(n(n-1)) / (n - 2) | NIST/SEMATECH e-Handbook of Statistical Methods §1.3.5.11 |
| Interpretation | G1 > 0 indicates right skew (long right tail); G1 < 0 indicates left skew | NIST/SEMATECH e-Handbook of Statistical Methods §1.3.5.11 |