Jerzy Spława-Neyman (April 16, 1894 – August 5, 1981; Polish: [ˈjɛʐɨ ˈspwava ˈnɛjman]) was a Polish mathematician and statistician who first introduced the modern concept of a confidence interval into statistical hypothesis testing[2] and, with Egon Pearson, revised Ronald Fisher's null hypothesis testing.

He was born into a Polish family in Bendery, in the Bessarabia Governorate of the Russian Empire, the fourth of four children of Czesław Spława-Neyman and Kazimiera Lutosławska.

He earned his Doctor of Philosophy degree at University of Warsaw in 1924 for a dissertation titled "On the Applications of the Theory of Probability to Agricultural Experiments".

He spent a couple of years in London and Paris on a fellowship to study statistics with Karl Pearson and Émile Borel.

He published many books dealing with experiments and statistics, and devised the way which the FDA tests medicines today.