Hope your long holiday weekend is full of good times. We've had a lovely few days hanging out soaking up the last bit of time before the Bug arrives (eeek!). We're trying to follow advice given to us by just about everyone we encounter, well, the people with kids anyway, that now is the time to go out to eat and be as social as possible. We have definitely been following that advice this weekend.
Speaking of the Bug's impending arrival, I have something fun to share with you today. For the first time in the six year history of this blog, my sweet husband, Dustin, whom I've mentioned in this space many, many times is going to share a little something -- yes, it will be his very first Curious Bird post evah. I know, crazy, eh? But first I must give you a little background as to how this post came about.
If you have been reading for a while, you have probably picked up on the fact that I am a lucky bird who happens to be married to a very swell man, a man with lots of talents (building a campfire, killing a crossword puzzle, changing a bike tube, taking excellent photos, and making a mean mojito are just a few that come to mind). Dustin also happens to be a scientist, a research psychologist/cognitive neuroscientist, actually. One of the things I love about him is the fact that he's way into geeking out with data and graphs and, well, RESEARCH! I find this all very exciting and, yes, sexy. So the other day when he mentioned he was exploring some new research software and using data related to our unborn child to teach himself how to use it, I loved the idea and thought it might be fun if he shared what he found with you, my Curious Bird peeps. So, here you go. Hang on to your hats, people. He's wordy and he made pretty graphs and everything!!
As Leya has alluded to many times over the past few years, I tend toward the geeky side of things. I spend most of my days engaged in some combination of the following activities: (a) reading obscure journal articles; (b) running experiments to investigate obscure questions; (c) using obscure statistical techniques to analyze resulting data; (d) writing papers that I hope will one day qualify as obscure journal articles. And, most of the time, I experience this as fun. So yeah, I guess the geek designation is fair.
Fine, you say, but what does this have to do with the birth of Junebug? And why are you writing now after all these years of silence?
Good questions. As you know, there have been a lot of predictions offered regarding what exactly the coming Bug will be. My mother is quite confident that the Bug is a girl, and she’s currently riding a perfect streak for predicting grandchild gender. (Nice job with Hazel, Mom.) And you guys appear to agree: out of 100 votes, 60 of you predicted girl. So should I just settle in and get ready for my baby daughter to arrive? Unfortunately, that would ignore a whole class of other predictions. For instance, the balance of unsolicited opinion from strangers on the Philly streets/subways has overwhelmingly tipped toward Boy. Perhaps most importantly, my trusted friend Atticus performed the closest thing to an experiment yet, and according to him, the pendulum unambiguously spun toward Boy.
And those are just the gender predictions. Everyone also seems to have an opinion on how big the Bug will be (Leya’s grandmother is really concerned about this) and when it will come (the interwebs say 15 days late for first babies by white women…). And then there was the Mysterio thing, which just said Flamenco Dancer-- I don’t know what to make of that. As you might imagine, all of this data-free intuitive hoolabaloo makes my scientific head spin. But how else to make predictions when we have no Leya-specific history of childbearing to provide even the scantiest of clues? Clearly, the only solution is to create a probabilistic statistical model based on means and standard deviations of the relevant variables (i.e., gender, DOB, weight), as known for the general population. Clearly.
Here’s the basic idea: It’s more-or-less impossible to accurately predict the what & when of any individual child birth, but it is possible to depict the most probable outcomes if we know what usually happens. Which we do. For gender, it’s pretty much a coin flip. For date of birth, babies on average arrive on their due date, but there is quite a bit of variability (about 50% of babies are born within +/- 1 week and 90% within +/- 2 weeks). For birth weight, we can consult a handy table for average weight based on gestational age. So I used a bit of fancy math to simulate what will happen when Leya has our baby. Because any one simulated childbirth is really no better than random, I did this 500 times. Before you completely freak out, let me clarify: this little imaginative exercise is not about what would happen if Leya gave birth to 500 different Junebugs, but rather 500 different imaginative attempts to predict what will happen when Leya gives birth to our one Junebug. Not sure if that makes sense, but I’m doing my best.
So hang with me here. Let’s start with Date-of-Birth and Gender:
Each dot on the graph represents a baby -- a possible Bug, if you will. The blue dots are Boy Bugs, and the pink ones are Girl Bugs. If you count the dots, they won’t add up to 500, but that’s only because in this particular hypothetical world, quite a few of the Bugs have already been born. The higher a stack of dots, the more likely the Bug will be born on that day. Notice the bell shaped curve -- most of the simulated babies are born on or close to the due date (10 Days Left), and fewer and fewer babies are born as you move to the left (earlier) or right (later) of the due date. And as you can see, the blues and the pinks are pretty evenly distributed, so there really is no way of knowing whether the Bug will be a boy or a girl. Sorry Mom. Sorry Atticus. I’m stickin’ with the coin flip.
Let’s move on to the birth weight…
So this graph is really just another version of the one above, except the color of the dots indicates the simulated babies’ weight-at-birth instead of gender. I calculated the weight based on average weights of babies born at the corresponding gestational age, with a little randomness thrown in for good measure. Obviously, the longer the Bug waits before coming into the world, the bigger the Bug is likely to be, as depicted by the increasing number of turquoise, blue, and violet babies as you move from left to right on the graph. One note is in order: this graph in no way takes into account the influence of genetics, which could very well come into play for this particular Bug. Leya and I are both on the tall side of things, and we both weighed 9+ lbs. at birth, so it would be reasonable to add an extra pound or so to each of the estimated babies’ weights in the graph. I just didn’t want to get too far ahead of the data.
So that’s that. I’ve always hated writing conclusions, and since this is a blog and not an academic paper, I’m going to go ahead and take the opportunity to refuse to conclude. The Bug will be pink or blue, and also either red, yellow, green, turquoise, blue, or violet. Probably not red. Possibly double-blue? Who knows? Let the waiting game begin…