Thursday, June 20, 2013

Thursday Quickie: the Fake Blake

I've written about false literary attributions before, but I found this one particularly amusing.  Apparently a librarian in England figured out that a poem (written in the 1980s) was being falsely attributed to William Blake (a poet from the 1800s).  Worse yet, this poem was actually being taught in multiple classrooms as an example of his work.

It's one thing when students don't check their sources, but teachers?  Come on guys.

Wednesday, June 19, 2013

Wednesday Brain Teaser 6-19-13

I think my one last week was too hard.  I'll provide the answer as soon as I can find it...I'm trying to remember which book I got it out of.

Anyway, here's an easier one:

A car travels at a speed of 50 mph over a certain distance, and then goes 30 mph over the same distance on the way back.  What's the average speed for the trip?

Monday, June 17, 2013

Self righteous hand washing

In honor of my little sister taking her nursing boards today, I thought I'd do a post about a pet peeve of mine: hand washing.  Well not hand washing exactly, but rather those who get worked up in to a foamy lather* when others don't do it.  Let me explain

I'm a fairly avid reader of advice columns, and there is a genre of letter that pops up every few months that goes something like this "Dear _____,  my coworker doesn't wash their hands and it makes me wretch and think they're a disgusting human being.  How do I confront them?"

Now these people are never hospital/patient care type employees, they tend to be just regular office workers.  What gets me so annoyed is that I have worked in patient care, and when I got my nurses aide license I even had to wash my hands in front of a state inspector.  Washing your hands is not easy and almost everyone does it wrong.  That's what annoys me about these letters.  Unless they're very meticulous, these people are likely not even being very effective themselves...and even if they are doing it effectively, nearly everyone else they work with is doing it wrong. Also, as someone who carries hand sanitizer around just to avoid having to insufficiently wash my hand in a public restroom, I get annoyed at people who think water = clean.

I thought about this today because I heard about a large scale study that vindicated my feelings:  95% of people do not wash their hands properly.  Properly means with soap, lathering for at least 20 seconds.  If you want to be good enough to get your nurses aide license, you also better use a paper towel to shut the faucet off, and angle your hands downward when you rinse to make sure you're not spreading germs up your wrists.  People are so bad at this that many hospitals now recommend that hand washing only be used to remove stuff that may have gotten on your hands, and that hand sanitizer is what should be use to disinfect.

I like studies like this because they are very useful for reminding people that our self-assessment does not always match reality.  My guess is that a very high percentage of people believe they are washing their hands correctly.  It's like how everyone believes they're an above average driver.

Anyway, best of luck to my favorite little sister, may you be several deviations from the norm (in the passing direction of course).

*See what I did there?

Sunday, June 16, 2013

NSA and Father's Day

Happy Father's Day to all those in the relevant group!

I saw my father yesterday, and we, like much of the country, spent some time talking about the NSA leaks and Snowden.   My father asked how I felt about it, and I answered in a way only a daughter who's been debating her father for decades could answer:  You already know how I feel about it Dad, we debated this years ago when Bush was President.  He was testing me. Nothing makes my Dad happier than knowing he raised kids who keep their opinions consistent regardless of who's in power.

At that point my Dad mentioned that he had seen a survey that showed that Democrats and Republicans have switched places when it comes to supporting programs like this.  Under Bush, Republicans supported NSA surveillance programs, now the don't.  Vice versa for the Democrats.  

I didn't have a chance until today to look up the survey my Dad was talking about, and I found a good breakdown at here.

There are actually 3 different polls cited:  one from 2002, one from 2006, and one from just recently.  The numbers do, in fact, flip (and 2006 is more dramatic than either of the other two years).  Eugene Volokh however, does an interesting take on the numbers, and points out a different spin:
If the 38% of Republicans who said no still say no today, and the 45% who say yes new said yes in 2002, that amounts to 83% (out of the average of 93.5% responding) whose answers were the same. Likewise, if the 41% of Democrats who said yes still say yes today, and the 43% who say no now said no in 2002, that amounts to 84% (out of the average of 94% responding) whose answers were the same. (I oversimplify here by assuming that the same people were surveyed today as before, despite the changing composition of the public overtime; but if you relax that assumption, then the consistency rate might be even higher.)
Those numbers actually sound pretty reasonable to me.  One also has to wonder how many of those 16/17% would actually admit they legitimately changed their minds.  11 years is a long time.  Even if you took the more dramatic 2006 numbers, about 75% of each party maintained their beliefs.

Now obviously it was not very likely that the same exact people were polled, so we don't actually have evidence that any individual changed their mind.  The one thing to keep in mind when you see polls like this talking about Democrat vs Republican attitudes is that the type of person who identifies themselves with either party is changing.  Here are the breakdowns of Dem vs Rep vs Independent for the 3 years listed:

              Dem      Rep      Ind
2002      31         30         30
2006      33         28         30
2012      32         24         38

  Even if these survey had polled the exact same group of people and they all had answered identically, the numbers would have changed based on changing political affiliation (or lack thereof).  Things to ponder.

Wednesday, June 12, 2013

Wednesday Brain Teaser 6-12-13

If you're finding my weekly brain teaser too low stakes, try this one, win a million bucks!

There are 11 ways of expressing the number 100 as a number and fraction using the nine digits once each.

91+ (5823/647) = 100

The challenge is to find some of the other 10 ways.

Hint: In 9 of them, that first number is above 80.  In one of them, it's less than 10.

Tuesday, June 11, 2013

Transitivity, bicycle helmets and teleoanalysis

I've mentioned before on this blog that I get annoyed when people link A to B and B to C and then proceed to assume that the relationship between A and C is just the average/sum/etc of the first two.  In pure mathematics, the technical term for this is transitivity and it tends to be pretty valid.

I learned recently that there is actually a term for this when applied to epidemiology research: teleoanalysis.  Developed in the realm of public health, it's defined as
the synthesis of different categories of evidence to obtain a quantitative general summary of (a) the relation between a cause of a disease and the risk of the disease and (b) the extent to which the disease can be prevented. 
It has also been criticized, in large part because it was invented to help support pre-existing assumptions.  Both papers I linked to reference the "does cutting back on saturated fat actually prevent heart disease" controversy as an example.

I was thinking of this recently when reader Dubbahdee sent me this article about bicycle helmet laws.  The issue follows the same formula as above:

A. Bicycle helmets protect cyclists
B. Mandatory helmet laws increase the number of cyclists who wear helmets


C. Bicycle helmet laws save lives

What's interesting is it appears this is not the case.  The paper's authors suggest that increased helmet laws decrease bike ridership, and apparently having lots of bicyclists in an area makes it safer for cyclists in general.  Also, helmet laws seem to potentially inoculate lawmakers against making any bigger changes...the sort that actually help cyclist safety (infrastructure building, etc).

I thought this was interesting because it's absolutely proven that you as an individual should wear a helmet, but the conclusions drawn from that weren't valid.  Someone out there guaranteed that these helmet laws would save x number of lives, and they were wrong.

Monday, June 10, 2013

Post migraine post

I had a nasty migraine last night that kept me up for most of the night, and I'm not sure I have a real post in me.

In lieu of that, I have a linguistic issue I'd like to get off my chest: Misnomer does not mean "error" or "misconception" refers to an error in naming.

I'm sure my very smart and wonderful readers know this, but 3 times in the past two weeks I've heard people make this error.  If you're going to try to use big/unusual words, please use them accurately.  Oh, and that also goes for phrases in Latin.  Saying part of your argument in Latin doesn't make you right.

Sunday, June 9, 2013

Sunday Fun Links 6-8-12

Good morning!  It's hard to find fun links this week.  Why?  Because George @#&$@* Martin wrecked my life.  Game of Thrones may land me in therapy.  I knew about the red wedding, but really George Martin, really?  Your life goal is to make your readers scared to turn the page?  Well you've got me.  Fine.  You win.

Alright, here we go, the New Yorker has an interactive map of the rise of the microbrews.  Little known fact:  there was an award winning microbrew in Texas named after me.  True story.

This here is possibly the most joyous/beautiful practical joke/prank I've ever seen.  It made me smile.

These are some pretty cool illustrations about how chemistry works.

Looking for some more summer reading?  How about a book that will tell you "what would Jesus drink?"

Thursday, June 6, 2013

Thursday Quickies: DNA and the legal system

In other DNA related news, Scalia's dissenting opinion regarding DNA sampling in Maryland v King was my favorite thing I read this week.

There's some interesting math behind the practice of using DNA matching as sole proof in criminal cases.  The stats are normally presented to the jury as though it was a one in five million chance the person is innocent...but if the size of DNA databases starts to grow, that could lead to several hits.  Additionally, the stats do not factor in the chance that the sample was contaminated, or the chance that your DNA ended up somewhere randomly rather than intentionally.

End message: it shouldn't be treated as perfect.

Thursday Quickies: Can I be in a Geico commercial now?

A few months ago now, I decided to get my DNA sequenced through 23 and me.  I got my health results back yesterday, and while I'm still waiting on the full ancestry results, I did get one interesting piece of information:  I share an uncommonly high amount of DNA with Neanderthal's.

Apparently your average person of European decent get 2.7% of their DNA from cavemen, and I actually have 3.2%.  That puts me in the 99th percentile.  I'm happy to finally have an explanation for why I'm so short and brutish.  

More on their science here.

Wednesday, June 5, 2013

Wednesday Brain Teaser 6-5-13

There is one four-digit whole number n, such that the last four digits of n^2 are in fact the original number n. What is n?

Tuesday, June 4, 2013

Dating and marriage in the age of the internet

In light of rule #6 from my post on Sunday, I thought I'd take a crack at this article I got sent by my wonderful (and single!) brother.  The headline reads "marriage from online meetings is more stable, satisfying".  In case you're curious, the study was sponsored by...wait for internet dating site.  

This doesn't actually make the finding illegitimate however, though it does indicate we should use some scrutiny.  

First, as I'm sure many of my older readers have already wondered, this study only focused on people who have been married at most since 2005.  Given some lead time for publication and all, that means that they were studying the incidence of divorce in marriages in the first 7 years or so.  Now this isn't totally crazy...about half of all divorces occur in the first ten years of marriage (This is what I learned in school, but now I can't find a good source for this, but this article seems to back me up), so this study does likely tell us something.  It's interesting though that the abstract uses the word "slightly" to describe the lower divorce rate/marital satisfaction.  It turns out that's pretty true, as the divorce rate for those meeting online is about 6%, and for those not meeting online it's 7.7%.  This difference was smaller when they controlled for other factors, but was still statistically significant (they don't list it).

Now I don't think this is totally crazy.  It's a small difference, but I would imagine that much of that could be attributed to people who went online looking for love/relationships vs people in the offline world who just fell in to relationships with people they encountered.  Actively desiring marriage would, I presume have a protective effect on said marriage once it occurs.

Overall though, it is interesting to ponder where this might go.  Are the divorce rates going to be higher once we get more than 7 years out? Are there other changes coming due to online meetings that we haven't noticed yet?  Additionally, there's evidence that the divorce rate is not continuing to climb because many who  would have gotten divorced are simply not getting married.  As those folks continue to opt out, how will things change?  I will be anxiously awaiting the eHarmony followup.

Sunday, June 2, 2013

Tales of the footnotes

I've written before about my 5 reasons you should check citations, and it occurred to me recently that I need to add a 6th.  Here's my updated list, changes in bold:

  1. Check that the source cited actually exists
  2. Check that the source cited backs up the part of the sentence that really needs backing up.
  3. Check that the source cited actually backs up the thing it's being used to back up, and doesn't just reference it obliquely.
  4. Check that the source cited states the point as strongly as the article authors state it.
  5. Check that the reference isn't so old as to be outdated, replaced, or from a paper that has been unreplicatable.
  6. Check that the reference was from an actual journal and/or otherwise reflects real scientific inquiry

I add this one on because the word "study" and "survey" get tossed around rather loosely at times.  Two examples that made me think of this:

First, from England:

Mr Gove said: “Survey after survey has revealed disturbing historical ignorance, with one teenager in five believing Winston Churchill was a fictional character while 58 per cent think Sherlock Holmes was real."
Those surveys, the Department has now revealed in response to an FOI request, included research conducted by Premier Inn, the budget hotel chain, UKTV Gold and “an article by London Mums Magazine”. None are known for their work in this field.

Mr Gove is apparently the British equivalent of the Secretary of Education.

Second was from a website with a rather interesting name (Manboobz).  The owner was apparently reading a book in which he saw the claim that schoolgirls hit schoolboys 20 times more often than schoolboys hit schoolgirls.  Upon investigating that citation, he discovered that it was not actually a formal study, but a class project a friend of his had assigned her students at his request.

These may both be small things, and the points they make may or may not be valid...but when in doubt it's always worth checking the source of the source.  The answers could be surprising.