# Seppo Linnainmaa **Domain:** Numerical Analysis / Automatic Differentiation **Doc Type:** Person Node **Maturity:** Foundational ## Definition **Seppo Linnainmaa** is a Finnish computer scientist whose 1970 master's thesis gave an early general formulation and implementation of [[wiki/Reverse-Mode Automatic Differentiation|reverse-mode automatic differentiation]]. ## Historical Context The thesis included FORTRAN code for propagating derivative information backward through composed operations. An English treatment appeared in _BIT_ in 1976. ## Sources / Provenance - Seppo Linnainmaa, _The Representation of the Cumulative Rounding Error of an Algorithm as a Taylor Expansion of the Local Rounding Errors_, 1970. - Seppo Linnainmaa, “Taylor Expansion of the Accumulated Rounding Error,” 1976. ## See Also [[wiki/Paul Werbos|Paul Werbos]], [[wiki/Backpropagation|Backpropagation]], [[wiki/Credit Assignment|Credit Assignment]]