Black metal is nasty stuff. Most of it revolves around Satanic imagery, shreiking vocals and guitars, incredibly fast “blast beat” drums, and spooky low fi production. Most bands hail from Scandinavia, and in the mid 90’s the nastiness reached a particularly nasty level as bands competed with each other to see who was the most evil by burning churches and murdering each other. And yet, I really appreciate the dark moodiness and musicality.

You can imagine my surprise when I found an honest-to-goodness Norwegian black metal band that is perfect for kids and adults. Now, whenever we get in the car, my two year old requests their music and proceeds to laugh and sing along! How did this happen? A confluence of two amazing things.

As I’ve already reported, my girls love the Rainbow Magic books. While the heros are Kirsty, Rachel, and the fairies, the villains are Jack Frost and the goblins. Their home is an icy castle north of Fairy Land and they are frankly hilarious. The goblins call each other names, trip over each other, and are some of the least scary “monsters” you’ll ever meet. I remember in one book Rachel and Kirsty got their way by tickling the goblins.

The band Immortal has been recording black metal since before their first full-length release: Diabolical Fullmoon Mysticism in 1992. Their music is classic black metal, but many of their songs simply describe frigid mountains and the grumpy king who reigns over them. B’s favorite song is “Mountains of Might.” It starts with organ which B says is “carousel music” and contains vocals which she calls “a goblin talking:”

The storm is getting colder
In a place of the frozen sun
Alone on the mountainside
Breathing the clearest winds
The winds are everblowing
Blowing off the glaciers
Snow descend of the valley
Into the high impassable drifts
So rightly I am watching
These mountains that I know
Forever standing here
These mountains northern face
Mountains of might
Mountains of might
Mountains of might
Icicled peeks as far as the eye can see
I will reign this place alone
Cold winds blew into the valley wall
Snow was deeper there
The storm is getting colder
In a place of the frozen sun
Alone on the mountainside
Breathing the clearest winds
Mountains of might
Mountains of might
Mountains of might

The acoustic break in the middle is when “the goblins are dancing.” The whole album (Blizzard Beasts) is recorded with the vocals mixed extra loud so they don’t get lost. My favorite part is how Abbath (the lead singer) pronounces glaciers as “glaysseers”. The lyrics of “Antarctica” (from Sons of Northern Darkness) are similarly child-friendly and the music is similarly goblin-friendly.

The only downside to Immortal for kids is common to all heavy metal: the terribly inappropriate music videos. Immortal follows black metal tradition and performs in corpse paint while making lots of scary faces. They also seem to love weird spiked bondage gear. They look ridiculous and I try to avoid their videos too. It doesn’t have to be this way. Consider the video below to be my small contribution to making the world a better place:

If you are excited to try and get your kids into other metal subgenres, make sure and check out my earlier post on this subject.

Spring has finally arrived in Connecticut. The snow is gone, replaced by snowdrops and crocuses, and the birds have returned. We’ve had great fun watching robins, bluejays, and red-winged blackbirds pulling on worms and building nests, and hearing their songs fill the air.

On the way home from school the other day we got an extra-special treat. As we drove by the reservoir, two hawks¹ flew over the car fighting over something. The birds were big and their prey was big too. The hawks dipped and dove and then lost control of their prize, letting it fall right into the street in front of us.

When it bounced and rolled to a stop we saw it was a huge fish! The whole rest of our trip home we wondered if the fish would still be there the next day and since it was a pretty busy street, hoped we wouldn’t see a road-killed hawk (or two) lying near by.

The next morning we were never so happy to see a dead fish all alone by the side of the road. We had to pull over so everyone could get out to take a closer look. Whoever said bird watching was boring?

Consumption, analysis, and creation. A lot of my time can be assigned to one of these three categories, and while all three have their place, I find it very easy to slouch into consumption and shirk creation. I feel better about myself when I’m in balance, so I’m always looking for opportunities to make things. That’s one reason the girls and I have been making up so many new games lately.

Our trips to the library have always been more than simply dropping off and picking up bags of books. We like to take our time and hang out too. These are our three favorite games to play while we’re there:

1. The Rug Game: The main branch of the New Haven Free Public Library has a huge children’s room and in the middle is a big circular rug with the alphabet and associated pictures printed around the edge. Since R was little we’ve played a game where I tell her to find something and she has to run to an appropriate letter. We started with the basics:

• Run to the octopus!
• Where is the dog?
• Find the birthday cake!

We moved on to more tricky questions:

• What keeps you dry in the rain? (Umbrella)
• Who has 8 arms? (Octopus)
• Find a red fruit! (Apple)

When other kids join in, the questions have to have at least two correct answers so everyone can find their own letter:

• Who swims in the water? (Fish, octopus, turtle)
• Find a fun toy! (yoyo, kite)
• What has a shell? (Turtle, egg)

As the kids get older, the questions get downright tricky:

• What rhymes with cry? (Pie)
• Who has a princess for a daughter? (Queen)
• Who is black and white? (Zebra)

2. Rainbow Magic: R is currently obsessed with this series of beginning chapter books. They are formulaic in the same way Dora and Boots are formulaic beginning readers and The Hardy Boys are formulaic tween boy schlock. The books come in sets of seven (e.g. The Pet Fairies) and each book involves two girls (Rachel and Kirsty) helping a particular fairy retrieve some magic item before Jack Frost and/or his goblins can get it. The books are quite harmless, and the thing is kids like formula–figuring it out is like solving a puzzle. B is not so into the stories yet, but she’s been swept up in R’s enthusiasm, and at the library she loves to gather up a big pile of the books, pore over the covers, and flip for pictures of goblins. We recently made up a game where she files her books by the first letter of the fairy’s name on the alphabet rug. Fun and even a little educational!

3. Picture Book Scavenger Hunt: This is a game I’ve been trying to get the girls excited about for years, and during our last library outing it finally took hold. I made a list of animals, characters and objects, and the girls had to find a picture of each in a book. We settled in between two big shelves and started digging. It was surprisingly difficult–I would have told you that a third of all picture books contain princesses, fairies, pirates, and dogs. It turns out dogs are easy to find, but everything else took a little hunting.

I’ve written a lot recently about games we’ve made up and had a good time playing. I hope some of you are inspired to try a few out. I hope even more that you are inspired to create your own games. That’s the most fun of all.

I was talking to one of R’s former pre-school teachers the other day, and she mentioned a board game she used to play with her daughter and husband called Pretty Pretty Princess. It involved moving pieces around the board (ala Candy Land) and collecting real jewelry that you get to wear. You win when you put on the tiara and shout out “I’m a Pretty Pretty Princess!” My first thought was that both of my girls would love this game and I should look for it on Amazon as soon as possible.¹ My second thought was that we already owned most of the parts and it would be even more fun to make the game ourselves.

We started by rolling out a big piece of paper and taping it to the dining room table. I drew a winding track and divided it into spaces. The girls went to town with their markers and drew bracelets, necklaces, rings, and earrings all over the board while I tracked down some dice (not hard) and our tiaras. We selected our game pieces from our bag of Schleich animals and My Little Ponies, grabbed our kids’ jewelry box, and started playing.

Rolling the dice and moving her piece the right number of spaces were challenges for B (not quite three years old), but picking jewelry out of the box made it all worthwhile. R enjoyed the game even though the pace was a little bit slow. We’ll play this version a few more times, but I’m already looking forward to making it more complicated by adding forks in the road, special squares, and some weird rules.

Footnotes:

This post has moved to Teach Better.

This post has moved to Teach Better.

It’s been a rough winter filled with snow days and sickness and not enough sleep. Tonight the wind is howling and the temperature is supposed to drop to the single digits. To get us in the mood for spring, the girls and I hunkered down in front of YouTube to hear Twilight Sparkle and the rest of the My Little Ponies sing “Winter Wrap-up”.

In the video, the ponies are also tired of winter and are preparing for spring. Actually, scratch that, they aren’t getting ready for spring–they have decided it’s time for spring and they are physically bringing it into being. The Pegasus ponies are annihilating the storm clouds and removing the snow from roofs and trees. Apple Jack and the other earth ponies are plowing the snow off the fields and lakes, and planting seeds. Fluttershy is waking up all the hibernating animals with a little bell. That’s when it hit me: These ponies are not mere cartoon characters at all–They’re gods!

The rulers of Equestria (Princess Celestia and Princess Luna) are obviously the old gods of the Sun and Moon. I’m surprised they aren’t named Princess Ra and Princess Khonsu. It also turns out each of the Mane Six ponies has a clear analog in Greek mythology:

• Twilight Sparkle is Athena, Goddess of Wisdom.
• Pinkie Pie is Dionysus, God of ritual madness and ecstasy–aka partying.
• Rainbow Dash is Hermes–the winged messenger of the gods who is quick and cunning and patron of athletics and sports.
• Apple Jack is Demeter, Goddess of the Harvest.
• Rarity is Aphrodite, Goddess of Beauty and Love.
• Fluttershy is Artemis, Protector of the Animals.

I think spring had better come soon before I go completely insane.

Hurry up ponies!

I’ve recently learned three bits of trivia that only a statistics nerd could love. They won’t help you think deeply about data. They won’t help you analyze data. In fact, they’ll probably push useful knowledge out of your head and make you dumber. Read further at your own risk.

1. Where does the word “logit” come from?

One of the earliest probablistic models of a binary process is the probit. It was developed by Chester Bliss in 1934, and in this paper he coined the term as a shortening of the phrase “probability unit”. The idea is that a one unit increase in an independent variable changes the probability of the outcome occurring by a constant number of probability units. Probits can be translated into actual probabilities using a particular non-linear transformation: the cumulative distribution function of the standard normal. That is, we have:

$$\Pr(y_i) = \Phi(\beta_0 + \beta_1 x_i)$$

In 1944, Joseph Berkson developed a similar model that also mapped the real line to the (0,1) interval, this time using the logistic function:

$$\Pr(y_i) = \frac{\exp(\beta_0 + \beta_1 x_i)}{1 + \exp(\beta_0 + \beta_1 x_i)}$$

By analogy, this model was given the name logit.

2. Why does Stata store dates as the number of days since January 1, 1960?

Nick Cox knows a lot about Stata, and even he does not know exactly why this date was chosen as the origin for internal dates. His best guess is that it was copied from “some data base or spreadsheet program”. My guess is that Stata copied SAS which uses the same date as the date-time origin.

This led me to wonder why SAS chose the date, and Derek Morgan (in The Essential Guide to SAS Dates and Times) says “One story has it that the founders of SAS wanted to use the approximate birth date of the IBM 370 system, and they chose January 1, 1960 as an easy-to-remember approximation.” According to Wikipedia S-Plus also uses the same reference date.

3. How are we supposed to pronounce McNemar’s test?

Suppose you have a set of matched pairs of observations and want to know if the distribution of some categorical outcome is the same for each side of the pair. You should use McNemar’s test to see if the observed differences are statistically significant. I went years pronouncing Quinn McNemar’s name as “mik-nee’-mahr” and getting likely getting laughed at behind my back by biostatisticians. It turns out the proper pronunciation is “mak’ne-mahr”. Ashwini Kalantri pronounces it well as he explains how it works.

Note: The pretty math equations are rendered with Mathjax and integrating this with Javascript was trivial thanks to Lucy Park.

In the past few weeks this blog has achieved two big milestones: December 21 marked the second anniversary of my first post, and on December 30, I published my 100th article. To mark the occasion, I thought it would be fun to reflect on the past two years quantitatively.

In 2012, I published 54 articles with 29,699 words, and in 2013, I posted 44 articles with 27,938 words–a decline, but not a major one. The average length of an article went up (550 words vs. 635 words) as did the standard deviation of the word count per article (296 words vs. 394 words). The increasing variance on this dimension can be seen visually in these two overlaid histograms:

So is this blog high variance in article length? That’s hard to say without scraping a bunch of other blogs and analyzing the data. Matt Gemmell says the distribution of his article lengths is bimodal:

When I’m not writing to a count, I have two natural lengths of piece:

• 700 to 1,000 words for a compact exposition on a topic. This is also an ideal bite-sized chunk of text for the reader, and fits well on a single page. It’s no coincidence that the majority of commissioned magazine pieces fall into this band.
• 2,000 to 3,500 words for a more detailed exploration or discussion.

The zone between the two is a death march.

I seem to have one natural length, but its range is a bit broader than Matt’s shorter pieces, as only half my articles fall within 369 and 724 words. If you include Matt’s longer pieces, he clearly wears the higher variance crown.

The yearly numbers mask an interesting monthly pattern. While I wrote a little less in 2013, I was more consistent in my output during the year. In both years I started strong, gradually slowed down, and then picked up the pace again in the fall:

Most article content seems to have settled into a small set of categories (tech, kids, education, and music. You could even make an argument that you’re reading a mixture of four distinct extremely low-traffic blogs with the occasional off-the-wall post thrown in. The below picture shows article counts by tag for each year for each tag that had more than one article. Many articles are tagged more than one way and every article I’ve published had at least one of the tags shown below. I wrote a bit more about education and Conan in 2013 and a bit less about music, but I’m not sure those trends will continue in 2014.

On the demand side, High Variance had 8,504 unique visitors in 2013 (up from 2,017) and 13,809 page views (up from 4,000). Chris Blattmann pointed his firehose my way in mid-April, but even if I ignore that week (961 unique visitors and 1,578 page views), readership is still way up for the year.

To celebrate, I’ve made a few minor tweeks to the site. First, I’ve added an IFTTT rule that tweets every time I post something new. You can follow me at HighVarianceNet. Second, I’ve made it easier to share content on the site by adding links for tweeting articles and sharing them on Facebook. Third, I’ve signed up as an Amazon associate. That means if you follow a link from this site to Amazon and then buy the product, you’ll pay the same price but I’ll get a few cents. Maybe by the end of next year I’ll be able to celebrate with a free cup of coffee.

When I was growing up, none of the several clocks in the house told the correct time. My mother would set them all between 5 and 30 minutes fast in an effort to fool herself into leaving the house when she was supposed to. I thought this was completely insane. Why not just wake up early enough to do what you needed to do, and then do that? Why play these games with yourself when pure rationality would suffice?

The answer (of course) is that my mother is far from completely rational, and this system worked for her in a way that my proposed system just didn’t. And while I like to think that I’m not as crazy as my mother, I’m not an automaton either. It’s taken me a long time to give in to that and start exploiting some of my foibles for good.

A few weeks ago, I read an article by my productivity sensei (David Sparks) where he recommended an iPhone app called Habit List for folks trying to kickstart good habits. There’s some scientific research that says if you can somehow get yourself to do something regularly for a few weeks, it becomes a lot easier to continue doing it. There’s also some evidence that games can be addictive. In a nutshell, Habit List makes doing mundane things into a game. By the time you’re bored with the game, the habit has been formed.

Since I installed Habit List, I’ve managed to floss every day except one (thanks stomach flu!). My exercise program has been less successful, but that’s more the fault of the cold weather and that same stomach flu than a failure of the app. You can bet that I’ll be plugging in some more easy-to-ignore-but-good-for-me chores soon.