Before revision: We investigate how and to what extent the Japanese government intervened in the rice futures market in Osaka during the interwar period, from the late 1910s to 1939, using a time-varying AR model .
After revision: We investigate how and to what extent the Japanese government intervened in the rice futures market in Osaka during the interwar period, from the late 1910s to 1939, using a time-varying VAR model to compare market efficiency and the government's actions over time .