GEV Shape Parameter

How it works

Evidence quality

Highlighted claims

• The shape parameter remained strictly negative for almost all countries and years in the study. — Socio-economic constraints to maximum human lifespan
• If the shape parameter becomes non-negative, the fitted GEV distribution no longer has a finite upper bound. — Socio-economic constraints to maximum human lifespan
• The shape parameter separates Fréchet, Gumbel, and reversed Weibull limiting distributions. — Socio-economic constraints to maximum human lifespan
• A flat negative shape-parameter trend would indicate movement toward a stable finite upper bound or wall of death. — Socio-economic constraints to maximum human lifespan
• Most countries showed an increasing shape parameter, implying movement toward loss of a finite upper bound. — Socio-economic constraints to maximum human lifespan