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Posts Tagged ‘Nate Silver’

Most people don’t know anything

Posted in Rant, tagged , , , , , , on May 15, 2014| 6 Comments »

[Note: this is the article that I wish Nate Silver would write.  He’d be so much better at the number crunching.  Of course, he’s also paid a lot more.]

I’m tired of hearing pundits spew their opinions about this, that, or the other.  Let’s face it, most people don’t know anything.

Of course, that includes me, but hey: this is my blog.

I’m using hyperbole; it’s true.  And yet in a country where 9% of people think that space aliens may have caused the disappearance of Malaysia Air flight 370; in a country where 55.56% of Supreme Court justices are completely ignorant about the First Amendment; in a country where sizable numbers of people believe in a 10,000 year-old Earth, and where numerous people doubt facts like global warming, evolution by natural selection, and the supremacy of Matt Damon…in such a country, how can you really take anyone seriously?

OK; I take Neil deGrasse Tyson seriously.  But he’s earned it.

People (of every political ideology) spew forth talking points without any facts to back them up.  Hell, they spew forth talking points without any justification at all.  I have liberal friends who are against GMO foods…even though there is no reason to think they could ever be harmful, and in fact have already saved millions of lives.  (Trivia question: how did Norman Borlaug save a billion people from starvation and subsequently win the Nobel Peace prize?  Answer: genetically modified wheat.)

On the other side, all kinds of nifty-sounding talking points spew from the conservative font, again without even a shred of justification other than “well, that sounds right”.  For example, people claim that less government is good.  Shrinking government is a goal of Tea Baggers.  “Democrats want more government, Republicans want less government…everyone knows that.”  It’s become a cliche, and people don’t even question it any more.

But this is the information age.  We don’t have to rely on our gut feelings, or even our supposed “knowledge”, to evaluate claims like “less government is good”.  We have data.  Why don’t people look at the data and then make up their minds?

I’ll tell you why: because looking at data is hard work.  Let’s face it; most people just can’t do it.  Most people want to be told what to believe.  But I just got tenure, so I have some time.  Let’s try to get to the bottom of this.

It didn’t take me long to find this website, which has nifty (exportable) data on all kinds of economic indicators.  Hey, look, the USA is ranked 12th in economic freedom out of more than 165 countries.  Yay!  We’re doing OK.

What about the size of government?  This is harder to quantify, since it means different things to different people (for example, many Republicans want to “reduce” the size of the US government without touching our defense budget, which is a little like trying to lower world sea levels by draining the Mediterranean Sea).  However, the indicator “Gov’t Expenditure % of GDP” seems pretty good to me.

How does the USA do here?  Do we have a “bloated, huge, nanny state?”  Our spending is 41.6% of GDP.  This makes us rank 47th in this indicator, so about the 72-percentile.  We have a “bigger” government than about 72% of the countries on the list.

Who’s ahead of us?  The supposed “socialist” states are (Norway, Sweden, Findland, Denmark) of course.  Everyone “knows” they are entirely nanny states.  Also: France, the UK, Germany.  The usual suspects.  Liberal, bloated, big government monstrosities.

But also: Cuba!?  Libya!?  Bosnia!?  Iraq!?  Malta!?

Maybe Cuba fits well into the narrative.  Cuba is a Communist country, so of course the commies have huge governments.  (I personally think Cuba is an outlier, since its GDP is pitifully small).  But what about other Communist states?

Hmm.  The narrative is starting to break down.  China’s government spending is about 23.9% of its GDP, almost half the size of the US.  The commies in red China are spending half of what we spend.  Vietnam spends about 30.9% of its GDP.

The talking point that the USA has become a “bloated nanny state” doesn’t hold water.  We’re in the top one-third of spenders, it’s true; but our defense budget is Brobdingnagian to say the least; if you plotted “non-defense government spending as % of GDP” our rank would be much lower.  (Note: I lack the skills to do this…feel free to do so yourself.)

But all this is distraction.  Ultimately, I don’t even know if big government is inherently bad or good, and more importantly, you don’t either.  Admit it.  You’re just guessing.

But we don’t have to guess.  We can try to understand the data a little bit more.

It didn’t take long for me to stumble on the cute Where-to-be-born index, a kind of “happiness index” which takes multiple factors into account like quality of life, health, economics, and so on, in order to rank countries based on where you’d prefer to be born.  (Admit it: you’d rather be born in Australia than Bangladesh.)  So hey, I know how to use Excel: let’s plot Size of Government vs. Where-to-be-born and see if there’s a correlation!

Correlations

Firstly: there’s not much of a correlation (the R^2 value is only around 0.17).  This is not surprising; the size of government has little to do with anything.  (It certainly shouldn’t be the entire frakking basis for a political movement.)  But what correlation there is, is positive, meaning that as governments get bigger, people tend to get happier.  All the Viking countries are in the upper right.  And those Scandanavians are doing well, dammit!

Some countries stand out.  Russia and China are lower and to the left of the USA, meaning they have smaller governments (is that surprising?) but are also more miserable.  Cuba, though, is a huge government spender…why is that?  Also, what’s the deal with Singapore?  They’re happy and (apparently) almost an anarchist state.  Tea Baggers take note: emulate Singapore.

The main idea I want you to get out of the graph is this:  there’s a lot of noise there.  You can’t really draw any conclusions.  If you want to say that “Big Government Bad!” in the same way that Tarzan says “Fire Bad!” you’d better have some data to back up your claim.  And finding such data is, well, hard work.  Good luck.

And now I’d better get back to studying something I know about: physics.

 

 

 

 

 

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The mathematics of going viral

Posted in Uncategorized, tagged , , , , on October 29, 2013| 15 Comments »

Up until Oct. 7, 2013, my modest blog averaged about 18 hits per day.  Then this happened:

VIRAL

A post of mine, the 9 kinds of physics seminar, had gone viral.  I was shocked, to the say the least.

I spent some time investigating what happened.  The original post went out on a Thursday, Oct. 3.  Nothing much happened, other than a few likes from the usual suspects (thank you, John Zande!)  I did share the post with Facebook friends, which include not a few physicists.  (Note: I don’t normally share my blog posts to Facebook.)  Then on Monday, Oct. 7, the roof caved in.

It started in India.  Monday morning, I had over 800 hits from India.  My initial thought was that I was bugged somehow.  But soon, hits started pouring in from around the world, especially the USA.

And then it kept going.

On Tuesday, Oct. 8, the Physics Today Facebook page shared the post, where (as of today) 451 more people have shared it, and 188,000 people have liked it.  (Interesting question: my blog has only had 130,000 views.  Are there really that many people who like Facebook posts without even clicking on the link?)

The viral spike peaked on Wed., Oct. 9.  I had discovered by then that my post had been re-blogged and re-tweeted numerous times, by other physicists around the world.  If you Google “The 9 kinds of physics seminar” you can see some of the tweets for yourself.

Why did the post go viral?  Who knows.  I’m not a sociologist.  I think it was a good post, but that’s not the whole story.  More importantly, the post was funny, and it resonated with a certain segment of the population.  If I knew how to make another post go viral, I’d do so, and soon be a millionaire.

What’s fascinating to me, though, as a math nerd, is to examine how the virality played out mathematically.  Here’s how it looked for October:

Chart 1

I don’t know anything, really, about viral cyberspace, but this graph totally matches my intuition.  Note that for the last few days, the hits have been around 400/day, still much greater than the pre-viral era.

After the spike, is the decay exponential?  I’m not a statistician (maybe Nate Silver could help me out?) but I do know how to use Excel.  Hence:

Chart 2

The decay constant is 0.495, corresponding to a half-life of 1.4 days.  So after the peak, the number of hits/day was reduced by 1/2 every 1.4 days.

This trend didn’t continue, however.  Let’s extend the graph to include most of October:

Chart 3

Over this longer time span, the decay constant of 0.281 corresponds to a half-life of 2.5 days.  The half-life is increasing with time.  You can see this by noticing that the first week’s data points fall below the exponential fit line.  It’s as if you have a radioactive material with a half-life that increases; the radioactive decay rate goes down with time, but the rate at which the number of decays decreases is slowing down.  (Calculus teachers: cue discussion about first vs. second derivatives.)

Maybe this graph will help:

Chart 4

The long-term decay rate seems to be 0.1937, corresponding to a half-life of 3.6 days.  At this rate, you would expect the blog hits to approach pre-viral levels by mid-November.  I doubt that will happen, since the whole experience generated quite a few new blog followers; but in any case, the graph should level off quite soon.  What the new plateau level will be, I don’t know.

Where’s Nate Silver when you need him?

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If you enjoyed this post, you may also enjoy my book Why Is There Anything? which is available for the Kindle on Amazon.com.

sargasso

I am also currently collaborating on a multi-volume novel of speculative hard science fiction and futuristic deep-space horror called Sargasso Nova.  Publication of the first installment will be January 2015; further details will be released on Facebook, Twitter, or via email: SargassoNova (at) gmail.com.

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Why the Zimmerman verdict doesn’t matter at all

Posted in Rant, tagged , , , , , , on July 19, 2013| 3 Comments »

I am going to argue that the Zimmerman verdict (for the shooting of Trayvon Martin) was the correct one.  You will either agree with me or you will not.  And then I will argue that either way, it doesn’t matter in the slightest to most people’s lives.

Let me just say, before you dismiss this post entirely because of some preconceived notion about my politics, then I am very liberal on social issues.  (As I’ve mentioned in the past, I literally don’t have an opinion on many complicated economic issues.)  I’m strongly supportive of privacy rights, voting rights, women’s rights, LGBT rights, and animal rights.  I think the idea of building a giant wall to keep out every illegal alien is absurd.  I am for the legalization of marijuana and for the decriminalization of other drug use in general.  I think man-made global warming is a self-evident fact.  I think big monolithic corporations, in the long term, have a negative effect on the happiness of the masses because they operate as entities without conscience, self-awareness, or humanity.

But when the Zimmerman verdict came back on July 13 as not guilty, I wasn’t surprised.  I wasn’t even outraged.  I just sort of shrugged and moved on.

Granted: there is still racism in this country.  I will even argue that there are often two disparate systems of justice in the U.S.: one for whites, and one for non-whites.  But still…what does that have to do with the Zimmerman verdict?

Scenario 1.  Let’s suppose the George Zimmerman is a total card-carrying KKK racist.  He may be, he may not be…I don’t have any evidence one way or another.  And most of you don’t, either.  But let’s just suppose he is.  Let’s say he follows Trayvon Martin looking for trouble; hoping for a confrontation; hoping to scare the boy.  A scuffle ensues and Martin is shot.

Is that murder?

I’m not a lawyer, but it doesn’t sound like murder.  Manslaughter seems a better fit.

Scenario 2.  Let’s be more realistic.  Let’s assume Zimmerman is a racist, but not the frothing-at-the-mouth kind.  He just feels uncomfortable having a black guy in his neighborhood.  However, if you asked him, he’d claim to not be a racist, claim to have black friends, and try to seem like a reasonable guy.

He follows Martin, hoping to scare him off, but not actively hoping for a fight; he genuinely wants to keep the peace.  If Martin gets scared, well that’s OK: he’s got no business being in this part of town.  A scuffle ensues and Martin is shot.

Is that murder, or even manslaughter?

Again, I don’t think so.  In this case, if Zimmerman is guilty of something, it’s…I don’t know…reckless endangerment?  Putting himself and another in a situation where only bad things could happen?

I didn’t follow the trial all that closely, but I will say that some people who followed the trial even less than I did were outraged at the verdict.  I can understand this, on some level; if a travesty occurs (the shooting of Trayvon Martin was certainly a travesty) then people want justice; they may even want revenge.  If Zimmerman wasn’t to blame, then who is?  Saying “the system” or “society” or “endemic racial profiling” are the root causes of Martin’s death isn’t satisfying, because you can’t put those nouns behind bars and throw away the key and feel good about yourself.  If no one gets blamed, then how does Trayvon Martin get justice?

Here are four ways Trayvon Martin could have gotten justice, or may still get justice:

  1. Florida’s inane stand-your-ground law gets repealed.  That would be justice.
  2. Community watch volunteers stop carrying guns and instead call trained police professionals if they see suspicious behavior.  That would be justice.
  3. Politicians stop listening to NRA lobbyists, and start listening to common sense: that would be justice.
  4. Zimmerman admits what he did was horribly bad judgment; pleads guilty to reckless endangerment; then performs 300 hours of community service as a sort of penance.  (In the long run this outcome would have been better for Zimmerman than the not guilty verdict, because I suspect Zimmerman may be a pariah for the rest of his life.  A little bit of remorse would have gone a long way.)

Anyway, all things considered, I think the jury did what 99% of juries would have done in this case, which was let Zimmerman go free.  The prosecution did not succeed in proving their case.  In retrospect, I think that going for a murder charge was ill-advised and entirely political; they should have aimed a little lower.  Going for manslaughter from the start had a much better chance of success.  Putting Zimmerman away for life on a murder rap isn’t justice; it’s revenge.

OK then.  Feel free to agree, or rabidly disagree.

It doesn’t matter.

The Zimmerman case was just one case.  One case, out of thousands of criminal cases in the U.S. every year.  That is, the Zimmerman trial was just one data point.

I’ve talked about this before.  You can’t really draw any conclusions about anything from one data point.  And yet, people do it all the time.  It’s a fallacy that probably has a name, but the name eludes me.  But to most people, it’s not a fallacy.  It has the weight of proof.

“I don’t believe in global warming.”  [Katrina devastates New Orleans]  “Wait, now I do!”

“I don’t think M. Night Shyamalan is a good director.”  [Watches The Sixth Sense] “Wait, now I do!”

“I don’t think racial profiling is a real thing.”  [Martin gets shot and his Skittles spill to the ground]  “Wait, now I do!”

I hope all three of these arguments is equally absurd to you.  If not, I think you lack the scientific mindset.  Now, don’t get me wrong: I think global warming is real, and I think racial profiling is real.  It’s just that you can’t make the case for those things with only one data point.  (Indeed, the case of M. Night Shyamalan shows that one data point can lead you horribly astray: after the wonderful The Sixth Sense Shyamalan has directed six turkeys in a row.)

I do think that racism still pervades the country.  I do think that whites get a different kind of justice than non-whites in our judicial system.  I do think that our country is obsessed…in an unhealthy way…with small metal devices whose sole purpose is to kill other human beings.  But I don’t believe any of these things solely because of a single data point.  You have to look at the big picture, look at the data in aggregate.  A preponderance of evidence is required to separate fact from fiction, truth from rumor, knowledge from urban legend.  As much as politicians love to bring up pithy examples, tell symbolic anecdotes, those examples and anecdotes are really rather meaningless.  Give me the data or go home.

And that is why the Zimmerman verdict is really rather meaningless.  Not to the family of Trayvon Martin, of course; I feel for them and am very sorry for their loss.  But as to what the trial says, in a larger context, about our society in general?  It says nothing.  A single data point says nothing.  It cannot say anything; that’s a simple mathematical fact.  It takes at least two points to make a line.

If you want to know how prevalent racism is, or how two “separate-but-equal” judicial systems pervade the U.S., or even whether putting guns in the hands of rent-a-cops endangers citizens, look at the data.  Data, plural.  Give Nate Silver a call.  Don’t argue by colorful anecdote.  And if you don’t have the hard data, at least have the courage to admit to yourself that what you believe is based on nothing.

That’s what I believe.  And yes, it’s really just based on nothing.  But I’m OK with that, because somewhere, hunched over a desk, Nate Silver is crunching all the numbers, and he’s still not a witch.

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Asteroid/meteor as a 1 in 100,000,000 coincidence? Not really…

Posted in Physics, Rant, tagged , , , , on February 23, 2013| Leave a Comment »

asteroid

CNN recently posted a story about how the Feb. 15 asteroid/meteor event was very, very unlikely: a 1 in 100,000,000 coincidence.  I disagreed.  I was all ready to blog about how CNN, yet again, got a non-scientist to write about science…and my indignation was already half out of the bottle.

Then I saw who wrote the article: Meg Urry, a highly respected Yale astrophysicist.

So, I sat on my hands for a second and re-evaluated the article.  It does not contain any errors as far as I can tell.  But I still contend that the article is misleading: saying that the asteroid/meteor event was a 1 in 100,000,000 coincidence is the wrong way to look at it.

I agree that if you multiply 1 in 3,650 days times 1 in 36,500 days you get something close to 1 in 100,000,000.  But all you’ve proven is that for any given random day, there is only a 1 in 100,000,000 chance of such a coincidence occurring.

However, we now live in a post-Nate Silver, post Bayesian controversy world, right?  We’ve known about asteroid DA14 for exactly a year (as of today).  So the right question to ask, before it flew by last week, was: what is the chance that a human-injuring meteor will fly by on the same day?  Well, given that an asteroid will already pass that day, the chance of a once-in-a-decade meteor flying by that same day is just 1 in 3,650 (that is, once in a decade).

I have the utmost respect for Dr. Urry.  I suspect that the hyperbole-filled title of her CNN post was written by a CNN webmaster, not her.  I still agree that the coincidence was unlikely, but given that DA14 was already expected to fly by, the Chelyabinsk meteor hitting on the same day does not sink into the realm of unbelievability.

[Trivia note: Chelyabinsk is the birthplace of Evgeny Sveshnikov, the chess grandmaster for whom the Sveshnikov variation of the Sicilian defense is named.  And I do know that, as much as I like the Sveshnikov defense, I tend to go down in flames like a meteor whenever I play it.]

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Mysterious Austrians

Posted in Uncategorized, tagged , , , , , , on December 7, 2012| 6 Comments »

Anton_Bruckner

Anton Bruckner was Austrian…

So I’m new to this whole blogging thing.  When I started, back around Halloween in 2012, I had no expectations about how many hits I’d get per day, or from what parts of the world.  I don’t even think I was aware of how much of this information a blogger actually has access to.

At WorldPress.com, a blogger can look at a “stats” page and see from what country the IP addresses of hits have come from.  And now, just six weeks in, I have some interesting data to play with.

As I write this, at 2:20 pm on Thursday, Dec. 6, 2012, I have had 1366 hits to my blog.  This does not include hits from my own computer(s) as long as I’m logged in as the owner of the blog; otherwise, the number would be around 600 hits more (I edit my blogs obsessively, even days after I’ve posted them).  As I would have expected, most of the hits are from the United States (87%) but I nice 13% are from other countries.  It’s the specific countries that have hit upon my blog that have piqued my interest.

map

Now, at #3, I have 29 hits from Australia.  This is not surprising; I have a good friend in Australia who follows the blog.  Almost all of these hits are presumably attributable to him (thanks Rick!)

But at #2, with 86 hits, is Austria.  This is strange.  I don’t know anyone from Austria, nor honestly anyone who’s ever been to Austria.  I lived in Spain for four years, and traveled around Europe, but never made it to Austria, unfortunately.

Even stranger is the hit data from today specifically.  I have 36 hits from Austria today.  I can’t even think of a plausible explanation as to why a post about teaching quantum mechanics would suddenly be popular in Austria.

Except, I can think of explanations.  Maybe one of my blog followers is from Austria?  As of 2:34 pm today, there are 14 people who follow this blog; of those, 8 are known to me personally (and don’t live in Austria).  Of the other 6, at least one is obviously in the United States from his profile.  That leaves 5 possible Austrians.  This is the most plausible, if prosaic, explanation.

There may be another explanation.  It’s very possible to follow a blog without “following” it.  I’ve had Nate Silver’s 538 blog bookmarked for 4 years now, without ever having “signed up” to follow it.  I just go to the site and occasionally read what he’s written.  Similarly, maybe someone in Austria stumbled upon ManyWorldsTheory.com, liked it, bookmarked it, and comes back here every so often.  OK, that’s fine; but why 36 hits just today?  For that to be the work of one person, they’d have to visit the blog, then exit out, then visit it again, a total of 36 separate times.  Seems unlikely.

One (speculative) explanation is that there is an Austrian physics professor who reads this blog, liked today’s post, and then had everyone in her/his class read the post today.  But maybe you can think of a better explanation.  Maybe you live in Salzburg and are laughing at my feeble attempts at detective work.  Enlighten me, or not, as you will.  It’s fun either way.

Here’s some more blog statistics trivia, just for fun:

Average number of (unique) hits per day: 36

Record number of hits in a day: 396 (on Nov. 6, 2012, the day before the presidential election; I shared this day’s blog post on Facebook which drove up traffic)

Search engine term that sent the most number of people to my blog: missouri proposition b 2012 (39 times)

Post with most hits: Economics don’t matter (267)

Science post with most hits: Einstein’s “Imagination is more important than knowledge” (36)

Least favorite post (not including today’s and yesterday’s): Let’s ignore Grover Norquist (16)

Country #4 in terms of hits: Spain, with 7.

Country #5 in terms of hits: Canada, with 5.

Part of the fun of having a blog is reaching out to diverse people all over the world, and maybe affecting them in ways that would have been impossible even 20 years ago.  And let’s face it, playing with the demographic data is fascinating.  Keep this in mind if you’ve ever thought about blogging yourself.  Maybe you’ll get some mysterious Austrians following you, too.

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Nate Silver was right, and he’s still not a witch

Posted in Rant, tagged , on November 7, 2012| 4 Comments »

This blog was supposed to be about science, not politics, so today (the day after the 2012 US presidential election) I will limit my comments to two brief points.  Then hopefully I will be able to forget about politics until 2014.

(1)    The election results shouldn’t be a surprise to anyone who’s a fan of hard data, scientific analysis, and cool-headed statistics.  On Monday, Nate Silver predicted an easy electoral college victory for Obama, and his predictions were spot-on.  Some ballots are still uncounted, and I don’t think Florida has been called yet, but as far as I can see he got all 50 states correct.  No, Nate Silver is probably not a witch; he just analyzed all the polls, and refrained from cherry-picking “one data point” to match some preconceived notion.  (In my opinion, media outlets just said the race was “close” because that’s what generates buzz and revenue.)  Nate Silver’s approach is moneyball all over again, but in the political arena.  (Knowing Nate Silver’s history with baseball prediction makes this statement all the more pertinent.)

I have friends who doubted Obama could win because of economic indicators that traditionally make re-election improbable.  There are two problems with this.  One is that the Republicans have shifted so far to the right of mainstream America on social issues that a tipping point has been reached: for many, it’s no longer the economy, stupid.  (See yesterday’s blog post.)  But another problem is that Americans, for better or worse, don’t tend to see the economy in absolute terms but in terms of change.  Objectively, the economy might have been bad; but it had been improving slowly but steadily since 2009.  As Nate Silver (the not-witch) put it back in August, “The economy is bad enough as it is, but voters in past elections have judged incumbents by the amount of progress in the economy, rather than how productive it is in an absolute sense.”  In physics terms, you feel the acceleration, not the velocity.

(2)    Ultimately, the bigger news might be the sea change on issues such as same-sex marriage and the legalization of marijuana, due in large part to younger voters.  If one looks at history—if one looks at social issues—one can only conclude that liberals always win in the end.  Monarchies are abolished, human rights are proclaimed, governments sever ties to religion, slavery is abolished, workers are unionized, women get the vote, disenfranchised groups gain civil rights, and humanity moves forward.  The writing’s on the wall.  All I can say is, get used to it.  Younger voters will all become tomorrow’s older voters.  No doubt tomorrow’s older voters will be dead-set against suffrage for cybernetic organisms, but that’s another issue entirely.

I’m stopping now.  Most of this blog is opinion, and in no way expresses the thoughts or opinions of theoretical physicists in general.  No wait: maybe it does.  Remember, a 2009 survey found that only 6% of scientists are Republicans.  I wonder why.

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