Connecticut-born Leonard Porter Ayres (1879–1946) was educated in the public schools of Newton, Massachusetts, and would go on to earn advanced degrees from Boston University (A.M., 1909; Ph.D., 1910). After completing his undergraduate studies in 1902, Ayres taught English in Puerto Rico, becoming superintendent of the island’s school system four years later. In 1908, he was appointed director of the Department of Education and Statistics at the Russell Sage Foundation in New York, where he applied statistical methods to a number of educational studies. Among these was a 1915–17 survey of Cleveland’s city schools commissioned by the Cleveland Foundation. Ayres’s critical report resulted in a number of changes within the school system.

At the outbreak of U.S. involvement in World War I, Lt. Col. Ayres volunteered to lend the Russell Sage Foundation’s statistical expertise to the Council of National Defense. After the war he moved to Cleveland, where he served for 26 years as vice president and chief economist of the Cleveland Trust bank. In 1940, Ayres was recalled to active duty as a brigadier general; he retired in 1942 and was awarded the Distinguished Service Medal. After suffering a fatal heart attack in Cleveland in 1946, he was buried in the National Cemetery at Arlington.