The Origins of Graphical Causal Models

Here is an interesting bit of intellectual history. In his 2000 book “Causality”, Judea Pearl describes how he got to the initial idea that sparked the development of causal inference based on directed acyclic graphs.pearl_causality_ch3

As you can see, the idea of thinking about interventions in quasi-deterministic systems is strongly rooted in econometrics (so no need for the not-invented-here-syndrome). In a sense, this story is also typical for the modern literature on machine learning, where smart computer scientists discover (some say “reinvent”, but that’s too disparaging for my taste) approaches from statistics and econometrics and take them to the next level. Because of his prior, Turing-award-worthy work on Bayesian networks, Pearl was able adapt the idea of structural causal models and equip it with a powerful symbolic language that allows us to solve problems far beyond what has been possible with traditional econometric techniques. Clearly, we have much to learn from each other and can only benefit from the convergence of interest from both disciplines.

If you want to know more about the history of graphical causal models and some of the amusing anecdotes around their origin (involving for example guinea pigs, but I shouldn’t spoiler), I can highly recommend you Pearl’s newest book “The Book of Why”, written together with Dana Mackenzie. It’s both an easily accessible introduction to the topic as well as an entertaining account of the last 25 years of Pearl’s research. On top of that you get some more funny rants about Karl Pearson—“causality’s worst adversary”. Definitely worth a read! :)

How We Started to Study Technological Change

In 1957, Zvi Griliches published a seminal article in innovation economics (Hybrid Corn: An Exploration in the Economics of Technological Change“), which is based on his PhD thesis. It is safe to say that this piece stands at the beginning of innovation developing into an independent subfield of economics. Besides that, Griliches was also a pioneer in modern style econometric work. In this paper you can clearly see why. It’s a marvellous combination of policy relevant work–he collected a novel data set on US corn production of the time–and advancement in economic theory. Continue reading How We Started to Study Technological Change

How to get knowledge out of the ivory tower?

Technology transfer is a big topic for scholars and policy makers.We would like to know how we can harvest the knowledge and ideas that are produced at universities and research institutes and to make them available to society. The invention of new technologies is only a first step. They need to be commercialized as innovative products and services to further foster a society’s wealth. Especially Europe could do better here. Continue reading How to get knowledge out of the ivory tower?