January 2018

S M T W T F S
  123456
78910111213
14151617181920
21222324252627
28293031   

Page Summary

Style Credit

Expand Cut Tags

No cut tags

August 11th, 2010

pozorvlak: (Default)
Wednesday, August 11th, 2010 04:25 pm
I was chatting to [livejournal.com profile] steerpikelet the other day, trying to come up with puns based on family saga novel-series and great feminist works (long story). Seeking inspiration, I looked up The F-Word's list of recommended reading, and was astonished to find Helen Fielding's Bridget Jones series there.

Bridget, for anyone who hasn't read the books or seen the films, is an astonishingly ditzy thirtysomething single woman living in London in the late Nineties. Her telegraphic diary entries all begin with a rundown of her weight and intake of calories, cigarettes, alcohol and Lottery scratchcards, with comments on same: "8st 13, alcohol units 5 (Jude's fault), cigarettes 2 (sort of thing that could happen to anyone — does not mean have started smoking again), calories 1765, Instants 2" being a typical entry. Or there's my favourite, from the second book: "Calories 22, unforgiving minutes filled with distance run 0".

Tracking these things is, of course, essential to controlling them. Unless you do it the way Bridget does - looking at only the raw data, and going into a panic at every pound gained. As everyone who's ever counted a calorie knows, your weight fluctuates from day to day and hour to hour based on all kinds of spurious and irrelevant facts like how full your stomach is and how much liquid you've been drinking in the last few hours. Which is why The Hacker's Diet (about which I have written before) recommends looking instead at a moving average of your daily weights, to extract the true picture from the noisy data. What, I wondered, would Bridget's trendline look like?

I couldn't find my copy of Bridget Jones' Diary anywhere, but fortunately it was trivial to find and download an ebook copy: think of it as format-shifting :-). A bit of mucking about with regexes and spreadsheets, and I had the following graph, for her weight and trendline throughout the first book:

It's a bit wide, unfortunately )

I have no idea what that sudden downward spike a third of the way along is: the entry gives her weight as 8st, but it passes without analysis or even comment in the text. OCR error, perhaps. Anyone with a treeware copy care to check out the entry for April 11? Anyway, note how the trendline is barely affected by such a sudden and swiftly-corrected change.

Overall, we see... not a lot. She pretty much maintains her weight in a five-pound band. A band, incidentally, which even the most fat-phobic doctor would be unlikely to criticise: assuming she's as tall as the average British woman at 5' 4", her BMI never goes over 23.5.

[I'm well aware of the problems with using BMI as a clinical tool; bear in mind that we're (a) only using it to get a rough idea, (b) talking about a fictional character here :-)]

The spreadsheet's here, if anyone wants to have a play with it.