Abstract :
This paper is concerned with the progress of Trygve Haavelmo’s research and
with his activities in general during his stay in the United States from June 1939
until the publication of his thesis “The Probability Approach in Econometrics”
~Haavelmo, 1944, Econometrica 12, Suppl+ 1–118! in July 1944+ His original intention
had been to stay in the United States only until the end of 1940, but the
outbreak of World War II and the German occupation of Norway left him stranded+
His “Theory and Measurement” treatise ~Haavelmo, 1941, “On the Theory and
Measurement of Economic Relations,” hectograph!, the first version of “The
Probability Approach,” was completed by the middle of 1941+ From 1942
Haavelmo worked in New York for the Norwegian government in exile and was
called upon to present his ideas to econometricians+ Throughout his time in the
United States he argued that probability should be accepted as an integral part
of economic theory and as a basis for verification in economics+ This paper considers
how much of Haavelmo’s approach was the result of his prewar experiences
and how much the result of his time in the United States+ It elaborates on
his contact with Jerzy Neyman, Abraham Wald, and Jakob Marschak and the
circumstances leading to the publication of “The Probability Approach+” Haavelmo’s
activities have been tracked through letters, seminar notes, and a reconstruction
of his itinerary+ The paper is a sequel to Bjerkholt ~2005, Econometric
Theory 21, 491–533!+
