Sunday, September 28, 2014

Gay rights vs national prosperity

The other day I saw a post on reddit via /r/bestof that was a counter to the claim that "Every civilization that has accepted homosexuality has failed".  I've never heard this argument, but I'll accept that some people actually claim it's true.  The rebuttal was a list of several modern countries that banned homosexuality and several that had many gay rights; the latter countries were the ones that were more well off.

While his argument seemed reasonable, it would be easy to fall victim to selection bias by picking the examples that you are well aware of.  I wanted to see if there actually was a correlation between gay rights and national prosperity.

Quantifying national prosperity is a common task.  I chose GDP (PPP) per capita, GNI per capita, GNI (PPP) per capita, and HDI.  HDI combines GNI (PPP) per capita with a education index and a life expediency index.

Quantifying gay rights was harder.  I knew of a survey that asked if gays should be accepted, but it wasn't asked in many countries.  I thought about using years that homosexuality had been legal or the punishment if it was still illegal.  However, as I was looking that up I found this Wikipedia page that listed 7 types of LGBT rights for each country.  They are: legality, civil union or similar, marriage, adoption, gays in military, anti-discrimination laws, and laws related to gender identity.  Each category has a green check or red x in it for each country.  I gave 1 point for a check, 0 for a x, and 0.5 points for both or a ? (eg, the US gets 0.5 for marriage since it's legal in some places and illegal in others).  Note here, that regardless of how you feel about those 7 things, it is safe to say that a country with more green checks is more friendly towards gays, and that is what we are trying to quantify here.

The results were pretty similar for each of the 4 measures of prosperity.  All were just about a 0.70 correlation between gay rights and prosperity, which is quite high indeed.  I used the 125 most populous countries.  Just for fun, I also looked at the correlation between population and gay rights, and as expected I found none (-0.04).

GNI (PPP) GNI HDI GDP (PPP) Population
0.70 0.68 0.69 0.68 -0.04

Scatter plots are always fun so here are some of those:


Wednesday, September 24, 2014

Odds of dying in shark attack vs driving to ocean

I've long held that there is a greater chance of dying in a car accident on the way to the ocean than there is of dying from a shark attack in the ocean.  I felt justified in this belief because I know car accidents are a large cause of deaths and that shark attacks are quite rare.  That being said, I never had any numbers to back this up.

The odds of a shark attack vary greatly depending on where you go swimming.  I had the idea briefly of making a map of the US that showed how far you'd have to drive from to equal the odds of dying from a shark attack there.  The problem was in estimating the number of swimmers in each state.

In fact, the only number for annual number of swimmers in the US was this Huffington Post article that claims it is 75 million.  This number seems high, and is unsourced.  The majority of people live near the coast, so it is possible that a quarter of them visit the ocean every year.

Number of shark attacks is easier to estimate.  Wikipedia lists 11 fatal attacks in the US in the 2000s, and 12 in the 1990sThis site lists 1.8 fatal attacks on average per year, and 41.2 injuries per year.

The NHTSA gives us the number for deaths per 100 million miles traveled as 1.13 in 2012.  I assume this includes miles traveled as a passenger. 

Using the 75 million swimmers figure, and the 1.8 fatal attacks and 41.2 injuries figures gives us these results:

You would have to drive 49 miles to have a greater chance of dying in a car accident than being injured by a shark attack.  You would have to drive 2.1 miles to have a greater chance of dying in a car accident than being killed by a shark.

There are a lot of caveats on these numbers.  First, I couldn't find injuries per mile driven, so keep in mind that 49 mile figure is dying in a car accident vs any shark attack injury, and it is also the round trip figure.

As I used the high 75 million swimmer figure, the shark attack odds could be higher.  That is 25% of the US population swimming in the ocean every year.  I would be surprised if the actual figure were lower than 10%, so that only increases the odds by 2.5, which means the round trip distance for equal odds of dying in a car accident vs shark attack would still only be about 5 or 6 miles.

Also, the vast majority of attacks in the US happen in Florida and Hawaii.  Avoid swimming in those two states and you reduce your shark attack odds to at least 1/4. 

Tuesday, September 16, 2014

Grain of sand sized piece of neutron star matter

So the realistic scenario would be, you reach out in curiosity to touch the grain of sand. Your fingertip gets 1 cm away, and you feel like it's being gently pulled on. You bring it half a centimeter closer, hrm, more of a pull, then you get to 1-2 mm away, and it suddenly feels like someone yanked on your nail as your finger suddenly snaps to the grain of sand (much like two closely spaced magnets suddenly snap into one another).

At that very instant, it feels like someone has grabbed a square millimeter of your fingertip with pliers, so you yank your arm back and that tiny little area on your fingertip is torn off in the process. Your fingertip now has a little crater on it, about 1mm in diameter, and looks like you had a teeny little wart removed.