Techniques of Attitude Change Hovland Research'Two-Sided Messages In one of his studies,Hovland wanted to measure army mens'opinions of how long the war in the Pacific would last.Before getting their opinions,two groups of men listened to a speaker whose main emphasis was that the war would last for at least two years.One group heard a one-sided message noting the problems of distance,the resources of Japan,the size of the Japanese army and the morale of Japan's citizens.The men receiving the two-sided message heard the same list mentioned to the first group, followed by a list of U.S.advantages over Japan (Hovland,Lumsdaine and Sheffield 469).The one- sided message was more effective for men who already believed the war would last at least two years, Techniques of Attitude Change • Hovland Research’ Two-Sided Messages • In one of his studies, Hovland wanted to measure army mens' opinions of how long the war in the Pacific would last. Before getting their opinions, two groups of men listened to a speaker whose main emphasis was that the war would last for at least two years. One group heard a one-sided message noting the problems of distance, the resources of Japan, the size of the Japanese army and the morale of Japan's citizens. The men receiving the two-sided message heard the same list mentioned to the first group, followed by a list of U.S. advantages over Japan (Hovland, Lumsdaine and Sheffield 469). The one￾sided message was more effective for men who already believed the war would last at least two years, whereas the two-sided message was effective for men that expected a shorter war (Hovland, Lumsdaine and Sheffield 475)