Joint Probability of Being Mauled by a Bear and Struck by Lightning

This is an oldie but a goodie. A while ago, Ms. Sarah Bailey posted this article on my Facebook wall about a guy who got struck by lightning and mauled by a bear. They go on to say that the closest estimate of the probability of both of these things happening is zero. Agreed... for any random person.

Every person, of course, does not have the same probability of being hit by lightning and being mauled by a bear. Take Donald Trump, for example. While Zeus probably hates him for being the most pompous shit ever, thus making him about 1,000 times more likely to be hit by lightning than the normal person, I'd hazard a guess that he is rarely if ever within 100 miles of an un-caged bear.

On the other hand, look at Rick Oliver. According to the article, "he tends to piddle about his farm, checking on his chickens, working on his tractors and, as he was in the wee hours of June 3, fixing up his Chevy Malibu." It was while piddling that, upon hearing a mysterious noise off in the distance, he went alone to investigate. I'd say that sort of behavior makes you pretty darn likely to be mauled by a bear. It might also make you pretty darn likely to get struck by lightning if that same tendency to investigate noises outside also applies to thunder. 

Two points here: (1) these events are not independent. They are probably conditionally independent given a number of factors, such as rural-dwelling, gender==male, a love of Kenny Chesney, etc.  (2) If you meet several of those conditions (i.e. if you're the sort of person who goes looking for bears/lightning), as rare as occurrences of bear maulings and lightning strikes are in the overall population, I'd say you're fairly likely to be attacked by both.

If your first language is Klingon, you probably also speak English.

I've always heard that the best way to learn a new language is by total immersion, so I didn't bother learning too much Portuguese before I moved to Rio de Janeiro about 10 days ago. Aside from having a dissertation to write before I left  (which I figured deserved the bulk of my effort... and sadly stole some  all of my bloggy time from me) I figured that just showing up in Brazil with one Portuguese course under my belt ought to be enough to get me up to speed pretty quickly. I imagined myself arriving in an exotic paradise, armed with a three year old's level of knowledge of the native language (and wit and charm galore), and smoothly transitioning into a carioca without being bailed out by anyone speaking English. Ever. I would of course also have an adorably irresistible accent.

This is only one of many fantasies I had about my life in Brazil that has not come to fruition... one of the other notable ones involves the inverse relationship between my desire to see any given Brazilian guy in his tiny little man-bikini-bottom and the probability that he will actually wear said swimming apparatus. Whenever I try to actually forge ahead with the Portuguese on a task like asking directions, which I can totally handle without help, thank you, the person I'm asking smiles amusedly at me and answers in English. However, when it comes to navigating Brazil's soul-crushingly burdensome bureaucracy or trying to set up an account with the Internet company, no one can help me. (Seriously, can someone help me get Internet in my apartment?)

Anyway, when my mom was here, she was stunned by how few people speak English. She commented that it is not like Holland, where it seems like just about everyone speaks English.  Having spent more than the 24 hour act-like-a-mature-adult-limit with my mom, I of course regressed to 14 year old me. "Duh, mom, of course they don't. _sigh_ Tons of people speak Portuguese, and hardly anyone speaks Dutch. If the Dutch didn't learn English, the only people they would be able to communicate with would be... the Dutch... and what good is that?" She didn't buy it, so I was forced to make some plots.

My point, I guess, revolved around the fact that it is not very practical to only be able to communicate with a very small community. So, if the community of people with whom you can communicate is large already, you'd be less likely to learn another language. (Go with this for a second, and assume that the chosen language would be English.) If you share your first language with relatively few people, you'd be more likely to learn English.

So, I snagged some data from Wikipedia (<3 you, W!), and I compare the the proportion of people in each country who speak English to the total estimated number of people world-wide who speak each country's official language. For reasons of laziness and ignorance about which languages are most used in every country, if more than one language was listed, I took the first. I also removed the countries that had English listed as an official language. The result of forcing several by-country lists  into one table and keeping only those countries that had all of the necessary data available was a table of 23 countries.

So, to be fair, having seen this I actually want to back-peddle a little bit. While there does seem to be a trend*, it looks like a spatial model or just taking continents (or even the wealth of each country) into account might explain some of this-- notice that Europe is mostly above the line and, darn you, Latin America,  is mostly below the line.

Point being, if you want to go on vacation in a place where you won't have many communication barriers, go to Iceland.** :)


*Yes, statisticians friends,  I do realize that fitting a line to data that only goes between 0 and 1 is not the best thing anyone has ever done... I have a super budget version of a logistic  regression fit to this also if this offends your statistical sensibilities too much.

** Not one of the countries in the plot. I'm just guessing.

Seasonal Insults

Some people from this project came to Duke this week, touting the greatness of their new method for approximate Bayesian inference and their sweet new R package. Though they didn't actually tell us how it works (apparently it is based upon some sort of advanced computational wizardry), I was excited to try out this new toy. If you browse the website, a lot of the examples are either time series (time serial?) or spatial. Since I deal with spatial data all the effing time, I decided to find some time series data and give INLA a whirl.

So, I present to you the schmuck dataset!

This is the relative search volume of the word "schmuck" weekly from some time in 2004 until yesterday. You could get it yourself off of Google Trends (thanks, Google! ), or you could just get a version here, from which I've already removed all of the extraneous junk.

Look at this beauty!! Something is definitely happening consistently during the 2nd week of December that makes people reaaaally want to search for the word schmuck.

Back to the statistics... using INLA, I tried fitting a latent AR(1) term to this even though that is clearly not the right model. No dice. I tried adding a seasonal component. Still no. It keeps shooting me an error message without much of an explanation. Something about a singular matrix. What matrix, I don't know. So, that's it in a nutshell. Although I was super pumped to take INLA for a test drive, this sort of knocked the wind out of my sails. This is not to say it doesn't work, just that I can't get it to work on my new favorite data set.

So, I leave you with one more seasonal insult, losers. Below you will find the relative search volume for the term "loser."

What is it about the cold months that makes people really interested in schmucks and losers? 10 units of pride to anyone who can give me a plausible explanation!