Friday, February 13, 2009

Dora Costa & Matthew Kahn's "Heroes and Cowards"

Dora L. Costa is the author of The Evolution of Retirement: An American Economic History, 1880-1990. She teaches at the University of California, Los Angeles. Matthew E. Kahn is the author of Green Cities: Urban Growth and the Environment. He also teaches at UCLA. Costa and Kahn are research associates at the National Bureau of Economic Research.

They applied the “Page 99 Test” to their new book, Heroes and Cowards: The Social Face of War, and reported the following:
Open to page 99 of Heroes and Cowards and you will see a bar chart displaying our estimates of the probability of desertion for four U.S Civil War Union Army soldiers --Adams E. French and James M. Rich both of the 36th Massachusetts Volunteer Infantry, Company D) and George Farrell, and Daniel Mulholland both of Company B of the 47 New York Volunteer Infantry. Using our unique 41,000 soldier data set, we document that on average 9 men out of every 100 deserted. Mulholland’s predicted probability of desertion was close to 30% which was six times higher than French’s. One of our book’s core questions is to ask: why did men differ with respect to their desertion propensities? We argue that fear of legal punishment cannot explain this. Unlike men fighting in Hitler and Stalin’s armies, a tiny percentage of Union Army deserters were caught and executed.

In our book, we argue that unit social capital, the desire to not let your comrades down, provided the glue for keeping the army together. Men who served in war companies with men who shared similar characteristics — a common religion, race, ethnic group, socioeconomic status, or even plantation in the case of former slaves — behaved markedly differently from their counterparts in more diverse companies. For starters, they had much lower desertion rates than the norm of one desertion per 10 Union soldiers. Union soldiers who served alongside men from the same occupations deserted at one-third the rate of counterparts in more diverse companies, as did former slaves who served with former slaves from the same plantation.

Stepping back, desertion during war time is just one of the choices and outcomes we examine in this book. In a similar spirit as Robert Putnam’s Bowling Alone, our book contributes to research on the causes and consequences of social networks. War time is a high-stakes life or death time. We study important war time choices and outcomes such as desertion and surviving deadly POW camps during war. We document that desertion and survival depended on a soldier’s war time social network. After the war, social networks affected later life experiences. Deserters were less likely to move back to their hometowns, especially if their hometowns were pro-War communities. We also study how comrades broadened soldiers’ horizons. After the war, men were more likely to migrate to communities that their fellow company mates were from. Our findings show that while there are many short-run benefits to being with men just like you, in the long-run men learned from those who were different.

A recent Wall Street Journal book review called our book “Military Sociology.” While we are economists, we are flattered that this reviewer recognized the interdisciplinary contribution that our book makes.
Read an excerpt from Heroes and Cowards, and learn more about the book at the Princeton University Press website.

--Marshal Zeringue