Friday, July 26, 2013
Brian Tamanaha’s Straw Men (Part 3): We use better (and more) data than studies Tamanaha praised in his book
BT Claim 3: 16 years of data is not enough
“S&M’s bold assertion that their 16-year study establishes valid ‘historical norms’ on law degree earnings would be scoffed at by social scientists who take the notion of ‘historical norms’ seriously. That is more than enough time to confirm norms governing the mating behavior of fruit flies, but 16 years is laughably inadequate for predicting something as complex and subject to change as the lifetime earnings of future law grads.”
Response Part 1: A fine idea for historical research
We will be delighted to read the results of similar work on earnings premia carried back into the distant past. We certainly are not claiming to have uncovered hundreds of years of data on law school earnings premia. But, ultimately, we are not sure how valuable such a retrospective would be for today's graduate.
Response Part 2: Professor Tamanaha and other critics of law school relied on—and praised—studies that use far less than 16 years of data
The literature has numerous studies using smaller data sets than ours (citations available), including several studies using only 3 years of data that were cited by Professor Tamanaha in Chapter 11 (starting on page 137-38) of his recent book, Failing Law Schools. Professor Tamanaha cited these studies without comment or criticism regarding the number of years of data used (although he did criticize them on other grounds), so we find it odd that he views our study as somehow deficient on this ground.
Professor Tamanaha and other law school critics have cited and praised studies that were much less rigorous and used much less data, including Herwig Schlunk’s “Mama’s Don’t Let Your Babies Grow Up to Be Lawyers.” Schlunk used a couple of years of data from Payscale.com, law.com, AbovetheLaw.com, and other websites.
The Economic Value of a Law Degree uses 16 years of data regarding earnings across age groups from the United States Census Bureau.
On page 217, note 18 of his book, Tamanaha called Schunk’s study “An excellent example of how [to determine whether a law degree is a good investment] in economic terms.” Tamanaha also praised an article by Jim Chen that used only starting salaries.
While we're happy to admit that no study is perfect, if these studies have enough years of data for Professor Tamanaha to cite in his book, then we struggle to understand his objection to 16 years of data across age groups.
And we're now going to take this opportunity to cite a personal favorite line from Professor Tamanaha's post:
“Let me also confirm that [Simkovic & McIntyre’s] study is far more sophisticated than my admittedly crude efforts.”
We'll take what we can get.
For a brief critique of Professor Schlunk’s work, see the discount rate appendix of The Economic Value of a Law Degree. A more thorough critique of Professors Schlunk’s work—and Professor Tamanaha’s reliance on it—is contained in our book review of Failing Law Schools, which will be posted on SSRN soon.