The Legacy of Andrew Isserman at the US National Science Foundation

Andrew Isserman received support from the US National Science Foundation (NSF), and he contributed to the agency's work by evaluating proposals. His most significant contribution to NSF was his proposition that cumulative knowledge associated with successive projects undertaken in a specific line of inquiry, which could be expressed as a logistic function taking the form of a sigmoid curve. This articulation has been used for more than two decades to assess when projects no longer yield the same levels of new knowledge as previous work in a line of inquiry. More recently, the Isserman Curve has become a part of the NSF Geography and Spatial Science Program's strategic efforts to identify and support potentially transformative research and research that may have especially significant longer-term value.