A discourse on the trials of the left-handed

Why is being a professor such a great job? There are a number of reasons, but one of the biggest is that your job is to learn new things all the time. If you are curious and open about the world, it's hard to beat this.

For almost all of the time I've taught at the Kennedy School, we have had a lunch every Wednesday at which a member of the faculty presents research he or she is working on. Because our faculty members do research on many fascinating topics — such as the impact of a pilgrimage to Mecca on the religious tolerance of Muslims or how performance in kindergarten is tied to success in later life — these weekly lunches are generally fun and mind-widening, especially because so many faculty members are working in areas so far from one's own.

This week, our presentation was by a young assistant professor named Josh Goodman, who works mostly on education policy issues. I have had a special fondness for Josh ever since he arrived two years ago because he has been generous in helping me with some methodological questions in my own research and because he grew up on the same street in Brooklyn where one of my daughters now lives.

His topic: How well do left-handed people do compared with right-handed ones in school and, at least in their early years in the workforce, in life? The presentation had a title with a nice mixture of academic irony and scholarly jargon: "On the Other Hand: Left-Handedness, Learning Disabilities and Human Capital Accumulation."

Josh found that some connections inside the brain and the parts of the brain used to process some kinds of information differ between left- and right-handed people, though there are no theories about why one kind of connection or processing location should necessarily be better than the other. This is, as academics often like to say, an empirical question. And Josh has good data from several large samples of young people about whom there is lots of data available, including school test scores and earnings into their 20s.

As a leftie myself, I was disheartened by what Josh reported to us. It turns out that, controlling for family background characteristics and even controlling for the outcomes of one's siblings, lefties do noticeably worse than righties on a number of dimensions. They have noticeably lower motor and social skills at age 2, they are more likely to have learning disabilities, and they do less well on English/math tests in school.

They are also significantly less likely to graduate from a four-year college. Again, controlling for background characteristics, 27 percent of righties complete a college degree, but only 22 percent of lefties do. And lefties have lower average income in their mid-20s than righties.

However, lefties are no more likely than righties to have committed crimes, had behavioral problems or be depressed. And it is not true, as some have hypothesized, that lefties are over-represented among both geniuses and dunces, with fewer in the middle.

I left the seminar thinking about how much I as a leftie had overcome to get where I am in life.