Saturday, November 21, 2015

Friday, October 11, 2013

Measures of central tendency, illustrated


Minimum wage, illustrated



Creative destruction, illustrated

More here.

Grad school, illustrated

Tongue-in-cheek first lesson in econometrics (plus addendum):

http://www.uibk.ac.at/econometrics/lit/siegfried_jpe_70.pdf
http://www.latrobe.edu.au/__data/assets/pdf_file/0004/251869/2013.02.pdf

Variance, illustrated

Source: "There has been an increase in the mean body-mass index since the 19th century but even more strikingly there has been an increase in the variance, what we might call an increase in weight inequality."

Negative externalities, illustrated

Earth orbit debris: an economic model
Space debris, an externality generated by expended launch vehicles and damaged satellites, reduces the expected value of space activities by increasing the probability of damaging existing satellites or other space vehicles. Unlike terrestrial pollution, debris created in the production process interacts with firms' final products, and is, moreover, self-propagating. Collisions between debris or extant satellites creates additional debris. We construct an economic model to explore private incentives to launch satellites and to mitigate space debris. The model predicts that, relative to the social optimum, firms launch too many satellites and under-invest in debris mitigation technologies. We discuss remediation strategies and policies, and calculate a socially optimal Pigovian tax.

Globalization, illustrated


Tuesday, August 27, 2013

Confidence intervals, illustrated


If you resample very many times, and compute confidence intervals for each sample, then a 95% CI means that 95% of those intervals will capture the true pop. value of the random variable.

Also, the larger your sample, the lower your margin of error:




Wednesday, July 24, 2013

Spurious regression, illustrated

Source:


There is a quadratic relationship between the percentage of males in a country who smoke and per capita health care spending. The relationship is statistically significant, as is shown in the table on the right.

The moral of the story? Don't conclude anything from regressions on country-level data.


The problem with analyses like this one is shown in the picture below. There is a very strong positive relationship between a country's income and the amount of money that is spent on health care: as income increases, health care spending increases. There is also a relationship - though a more complex one - between income and smoking. The poorest of the poor cannot afford cigarettes. As income increases, smoking rates increase. But in the most affluent countries, rates of smoking are lower again.

Saturday, May 11, 2013

Substitution effect, illustrated

Sin tax dampens San Miguel liquor sales

MANILA, Philippines – Ginebra San Miguel Inc, the beverage arm of diversified conglomerate San Miguel Corp, experienced a 30% drop in volume sales after the government implemented a higher excise tax on alcohol products.

Sunday, March 31, 2013

Some housekeeping

Henceforth I'm changing the blog's name from "Self-Illustrated Econ Nerd" to "Economics, illustrated". I figured the blog might better serve its purpose by simply curating excellent examples of economics in action through articles, graphics, and videos.

An old archive of my Economics, Illustrated blogs can be found at http://opinionator2010.blogspot.com.

Ciao!