prior probability

Hat tip: The Amazing Tyler Cowen.

Although most North Americans are celebrating Thanksgiving today, we must never forget that on this day 55 years ago (22 Nov. 1963) President John F. Kennedy was assassinated in Dallas, Texas. What if the presidential motorcade had continued down Main Street (further away from the book depository building where the assassin Lee Harvey Oswald was lying in wait) instead of going down Elm Street?

Credit: Donald Roberdeau

During a brief visit to my alma mater UCSB earlier this week (go Gauchos!), my wife Sydjia photographed this bike-path tunnel, which connects the main campus with the seaside college town of Isla Vista. In place of ordinary fluorescent tubes, the tunnel is now lit up by a geometrical pattern of lights.

Imagine interstellar trade occurring at the speed of light (or close to light-speed) across galaxies, such as the various constellations pictured below. The economist Paul Krugman imagines just such a science-fiction scenario in a beautiful paper titled “[A] theory of interstellar trade,” which was published in the journal Economic Inquiry in 2010. (An ungated version of his formal paper is available here.) In the paper, Professor Krugman develops a theory of interstellar trade in goods between planets in the same inertial frame and ends up making a remarkable claim: interstellar competition will equalize interest rates across constellations.

There is just one small problem with Krugman’s theoretical analysis: he neglects the crucial role that interstellar contracts and interstellar law must play before any trade could occur across the universe in the first place. Alas, this type of omission is common among economists, even first-rate ones like Krugman. Many economists like to take the existence of a well-ordered legal system and the enforcement of contracts for granted. But trade cannot occur in a (legal) vacuum. Trade and markets require some set of rules and the enforcement of those rules, and it is precisely these essential things that are lacking at the interstellar level!

It’s that time of year again!, the season when art critics, bloggers, and other assorted public intellectuals and pundits reveal their subjective listings of the best books, best music recordings, best movies, etc. of the year. In place of (or in addition to) such “best of” lists, however, we would prefer to see these same people tell us what they think the worst books, worst movies, or worst whatever of the year were.

What is “street art”? When people talk about street art they are usually referring to large-scale murals painted on walls, but earlier this week, we literally stumbled upon the micro-artwork pictured below, which was painted on a sidewalk on N.W. 26th Street in the whimsical Wynwood Art District in Miami, Florida. (Artist unknown.)

Photo credit: F. E. Guerra-Pujol