Spotlight, December 4, 2014: Timor-Leste (East Timor)
Image credit: weadapt.org
Timor-Leste is a country that takes up roughly half of a medium island in Indonesia. It has one of the highest fertility rates in the world (ranked 15th), with women having an average of five children during their lives. Almost half of its population is under 15 years of age. It has 16 indiginous languages and most inhabitants originally come from that island system, but there is also a small Chinese minority. Timor-Leste was internationally recognized as a country in 2002, but from 1999 to 2008 it suffered from uprisings by small numbers of Indonesia-supported anti-independence rebels who destroyed almost 100% of the country’s infrastructure. Even now, some of Timor-Leste’s country borders have yet to be officially defined, including its Maritime Exclusion Zone with Indonesia and some regions of its exclave, the Oecusse District. It’s four major industries are printing, soap-making, handcrafting, and weaving, but it has the 42nd highest industrial growth rate in the world, which isn’t bad for a country that has had to rebuild itself almost from scratch.
Source: “Timor-Leste.” The World Factbook. Central Intelligence Agency, 20 June 2014. Web. 03 Dec. 2014.
Spotlight, November 26, 2014: Kurtosis
Image credit: whatilearned.wikia.com
Kurtosis is a description of how sharply peaked a statistical distribution is and how far from the horizontal axis (how heavy) the tails are. The normal distribution has a kurtosis of 3 and moderately heavy tails and is called mesokurtic. Distributions that are pointier with heavier tails (farther above the horizontal axis) than the normal distribution are called leptokurtic, and those flatter than normal and with lighter tails are called platykurtic. Because of this relationship between the peakedness and the weight of the tails, leptokurtic distributions also have sides with greater curvature than the sides of mesokurtic and platykurtic distributions.
Sources: Weisstein, Eric W. “Kurtosis.” From MathWorld–A Wolfram Web Resource. http://mathworld.wolfram.com/Kurtosis.html (if you like math). Decarlo, Lawrence T. “On the Meaning and Use of Kurtosis.” Psychological Methods 2.3 (1997): 292-307. (if you like math drama)
Spotlight, November 17, 2014: Swan swim speed
Mute swan on the Limmat River near Zurich Hauptbahnhof.
Every day I commute into the city of Zurich, and I walk past swans and ducks cavorting or sleeping on the Limmat River by the train station. I noticed one evening that the swans can swim surprisingly fast. It turns out that swans are the fastest swimmers and fliers of any waterfowl, as well as one of the longest lived of all birds. I discovered that they can fly at speeds of up to 50 mph, but I was unable to find any information about their swimming speed. In fact, my Google search turned up several entries from Dwarf Fortress Wiki and one hit through answer.com (how fast do swans swim?). The answer provided for that question was “swans swimm so fast at lest 100 mile pore awer,” so it didn’t seem to me like the most credible source.
I decided to calculate my own answer. I measured my shoe (25 cm) and used my steps to pace off the length of a room (26 steps). Then I timed myself walking through the room at the pace I best remembered for the swan on the Limmat (13 seconds). That comes out to a standard traveling-perpendicular-to-the-current speed of 0.5 m/s or ~1.12 mph. Not bad. That’s faster than I can bike uphill.
Spotlight, November 7, 2014: Ẽṭo
Food customs in North India are influenced by the idea of ẽṭo (pronounced, as closely as I can determine: engtao). Ẽṭo can refer either to food which has come into contact with the eater’s saliva and therefore become permeated with his or her essence or to the state of being so permeated due to contact with the mouth or another object which is ẽṭo. Your hands can easily become ẽṭo if you hold a cup while drinking or a fork while eating, so you must wash your hands immediately afterward in order to prevent the spread of this ẽṭo condition.
By touching an object or food that another person has made ẽṭo, you take in some of their essence, so people are very careful around those from whom they wish to stay distant. On the other hand, people who wish to be close to someone else (e.g. a wife to a husband, a servent to an employer, or close friends or siblings among themselves) will often freely share food. Such fastidiousness likely prevents the spread of disease, and the custom provides a form of social structure.
Source: Lamb, Sarah. White Saris and Sweet Mangoes: Aging, Gender, and Body in North India. Berkeley: U of California, 2000. 30-34. Print.