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Chronocentrism and Retrospective Present Bias

I have discussed chronocentrism–“the egotism that one’s own generation is poised on the very cusp of history”–a few times on this blog (see here, here, and especially here). A few days before Christmas, I received an email from Star Tribune business reporter Patrick Kennedy, who had heard the term from an investment banker, and who wanted to chat about the concept. Here is what came out of a nice Christmas Eve chat:

We called Marc Bellemare, an associate professor of applied economics at the University of Minnesota who has applied chronocentrism to his work on the economics of global food policy, to further define the term made popular by British journalist Tom Standage, a science and technology writer for the Guardian newspaper and a deputy editor at the Economist.

Bellemare was happy to find parallels to the world of investing in explaining the concept. …

For investing, Bellemare pointed out that we look no further than the housing crash and the dot-com bubble.

He suggests chronocentrism leads to another economic concept called retrospective discounting, where our present bias leads us to put a lot of stock in the present and carefully pick and choose what we want to believe about the past.

The idea of retrospective (rather than the usual, prospective) present-biased preferences is how I see chronocentrism. That is, if we can give a greater weight to the present when looking forward, it is almost certainly the case that we also give a greater weight to the present when looking backward.

‘Metrics Monday: Why You Should Show a Regression of Y on Z

Happy New Year to everyone once again. Here is a quick ‘Metrics Monday post to start the year on the right foot.

Dave Giles had a neat post, sandwiched between Christmas and New Year,  titled “Correlation Isn’t Necessarily Transitive.” If you are not familiar with the concept of transitivity,* what this means is that when Y is correlated with D, and D is correlated with Z, Y isn’t necessarily correlated with Z.

From my choice of labels for those variables, you have probably guess why this is matters for applied econometrics: It is perfectly possible that in a regression of Y on D where you are interested in the causal relationship flowing from D to Y, you have an otherwise valid instrument Z (i.e., a variable that is plausibly exogenous to outcome Y and which is also relevant in explaining D). Obviously, Z being relevant means that it is correlated with D. Assuming that D is also correlated with Y, the fact that correlation isn’t necessarily transitive means that the IV is not necessarily correlated with the outcome.

Happy Blog Anniversary! (And Some Year-End Stats)

December 31 marked the fifth anniversary of this blog, so on top of wishing Happy New Year to all, I am also wishing this site Happy Blog Anniversary!*

December 31 also marked the close of this blog’s most successful year ever: Between 2014 and 2015, the number of page views almost doubled, increasing by 94.6 percent for a total of 134,951 page views coming from 79,710 visitors in 2015. (This is in no small part thanks to Mark Thoma‘s generous linking to my posts from his own blog Economist’s View, which anyone with an interest in economics should read.)

My top 5 posts of 2015 were, in descending order of popularity: