December 13, 2012
Also known as “math”.
Apparently some conservatives and other deluded souls believe that our appallingly low life expectancy is not a healthcare result, but is instead caused by excess (misclassified, not health-related) infant mortality and excess violence. This, like many conservative beliefs, is bullshit. Proof:
Suppose we have a “true” life expectancy, but two subpopulations that die early for non-medical reasons and drag it down. The “misclassified infant death” subpopulation dies at age 0, and accounts for about 0.003 of our deaths (that is, the excess US infant mortality rate is about 3 per 1000). The “murder death” subpopulation dies at an average age of 25 (a guess), and accounts for 15,000 deaths per year out of a total of 2,500,000 or 0.006 of our deaths. The reported US life expectancy is 78.37 years, and this is equal to the adjusted life expectancy * 0.991 + 25 * 0.006 + 0 * 0.003.
That is, adjusted = (78.37 – 25 * 0.006) / 0.991 = 78.93.
Without adjusting ANY OTHER COUNTRIES (Portugal’s infant mortality rate is better than ours, but not first-class) for worse-than-hoped infant mortality or murders, we move all the way from #49 to #44. That’s not much to brag about.
Update, the claim is it’s traffic accidents
Because I am feeling lazy and generous, I’ll assume average age 30, erase ALL of them, the death rate is 33,808/2,500,000 = 0.0135.
adjusted = (78.37 – 25 * 0.006 – 30 * 0.0135) / 0.9775 = 79.6.
That’s #37 in the list. USA! USA! USA!
That figure is overly generous and should not be relied on, because there are other countries between #49 and #37 with relatively high traffic death rates that would also be “corrected” upwards in the same way, among them Belgium and South Korea.
Further update — what if we try to factor in the exercise that we don’t get because we drive cars to excess?
That might matter. The years-of-life penalty is estimated to be 2-5 years, though it can be made up with other forms of exercise. +2 years takes us out of the embarrassing weeds, and up into the top ranks. However, again, one-must-apply-the-correction-equally; even in the Netherlands, even in Denmark, many people do drive automobiles to excess (how do you think they were able to do these studies in the first place?)
December 8, 2012
Fireplace ashes from urban trees are not a good idea for vegetable gardens. Trees, especially street trees, especially older trees (predating unleaded gasoline), picked up a lot of heavy metals, and burning the wood concentrates the metals in the ash.
And we may be mothballing a lot of nuclear plants in the coming years, and that might not be a good thing. Reaction to the Fukishima disaster has resulted in lots of new safety requirements (probably a good thing, but it is possible to waste money on excess safety, or misallocate it away from larger risks to further reduce tiny risks), and the low price of fracked natural gas means that nuclear plants have a harder time earning the money to pay for those improvements. That’s all fine, till the natural gas runs out.
September 3, 2012
You may have noticed the news that there’s less ice in the arctic this summer than at any time in recorded history.
What’s interesting is that back in 2007, a researcher at the Naval Postgraduate School came pretty close to predicting this — he suggested an ice-free summer as early as 2013. And then, conventional wisdom was ice-free somewhere between 2040 and 2100.
But look at what simple extrapolations of ice cap volume get us now, five years later:
And see how the extrapolations have changed over time:
That is, a simple fit back in 2007 would have predicted ice-free in 2019, and since then the predicted ice-free year has moved 2 years earlier.
What does this mean? One somewhat-modeled prediction is slower Rossby waves, which means that what ever weather we get (hot, cold, dry, wet), we’ll get it in longer-lasting doses. But the big official predictions (e.g., the IPCC reports) don’t incorporate any of this news; they’re still based on the assumption that there is some amount of Arctic ice cap for decades.
My personal prediction is that this next winter, or the next, when some large hunk of the US gets stuck under a long-lasting blob of cold Arctic air, that some head-in-the-sand moron will say “this proves that there is no global warming”.
Arctic Sea Ice blog (Good source of data, discussion, links)
And again, none of the “official” conservative models include this effect, because they assume the arctic ice cap persists for another 40 years, and not fewer than 4. This is a big warming change.
June 18, 2012
This is more or less a log, maybe I’ll bother Apple about it. The from-backup-disk install (Lion to Lion) was surprisingly good, but there were a few glitches:
- The command line tools for XCode were installed on the old system, but not the new.
- Java was installed/enabled on the old system, but not the new.
Whoops, one more glitch — it did not automatically transfer over my iTunes authorizations, or ask me if I would like that to happen. And for some reason, the store is not answering the request to authorize the new computer. DRM, I hate it. This is why I don’t buy DRM’d music anymore — not sure if iTunes store is or isn’t nowadays, because when I switched to eMusic, it was, and Apple hasn’t fixed the problem yet for the music I bought from them so long ago. (Dear RIAA: I curse you guys everytime this happens. Way to screw over your paying customers; the pirates deliver a superior product.)
Happiest surprise: realizing that with spaces and swipes (no idea how long these have been supported, but only with Lion did I start to pay attention), I could run my “Complete” New Yorker in its own screen-hogging “space”, and just swipe back and forth to it at my convenience. Next thing to try is to see if this same trick works for screen-hogging games like Civ 5; I fear it will not.
June 4, 2012
or why the Boston Globe really ought to do a cursory amount of fact-checking.
This article recounts the issue of deciding whether to get (expensive) rabies shots after a bat got into a house, and quotes a nurse as claiming that the risk of a rabies exposure in that situation was one in 400 million.
This reply asserts that this is an example of how risk intolerance raises medical costs, and also makes that claim that the drive to the hospital for the shots was riskier than the bat exposure.
It would be a gosh-darn shame if two articles took a bogus statistic for granted to make conclusions (really, to support pre-existing opinions) about our health care system and medical costs, wouldn’t it? If only we had a network of computers and data banks where we could look these things up and check them. Read the rest of this entry »
May 18, 2012
Consider this a bug report. Workaround is to disable iCal with extreme prejudice, and get BusyCal.
May 13, 2012
These are adapted from “Black Bean Chili”, The Greens Cookbook.
I cooked both of these for a party, several people liked them enough to ask about the recipes, so I am documenting exactly what I cooked for reference. This is doubled from the cookbook recipe, so you might want to either cut it in half or refer back to the cookbook, unless you really like beans or intend to freeze some for later. The cookbook includes other options for garnish; this is just what I cooked. (This is a great cookbook, and Greens is a great restaurant.)
The *first recipe* is just a particular set of choices from the cookbook recipe, doubled.
The [second recipe] is heat-reduced, because just before the party I realized that some people in the crowd would prefer less heat, guessed at some changes, and they tasted okay. There are only three ingredient differences between the two; the choices are indicated both with color and decorations. This is the *spicy choice*, this is the [cool choice]. The main rule is to cut out the hot chili peppers, and substitute paprika (less hot) for ancho powder (somewhat hot). The result is a LOT of paprika in the cool recipe (about 3/4 of a cup).
If you can’t find the powdered spices (ancho and chipotle chili, in particular), try Penzeys, either mail order or in Arlington Heights on Mass. Ave.
One thing to note is that this recipe is aimed at producing soft beans; this means that adding the tomatos and salt should be delayed as long as possible to ensure that the beans are soft (acid slows softening). Fresh beans are better; a bag that has been sitting on a shelf at home for who-knows-how-long is not a good bet. I bought mine from the bulk container at Whole Foods; I imagine La Chapincita in Waltham is a good choice.
I tried a pinch of baking soda and that seemed to help (a pinch here is perhaps 1/16 teaspoon, added to 2 pounds of beans) but I read that this can destroy vitamins (thiamine, in particular). There’s additional discussion here: apparently there is a tradeoff between preserving vitamins and making minerals and proteins accessible, and who knows what effect hours of boiling has.
Effect of Different Soaking Solutions on Nutritive Utilization of Minerals (Calcium, Phosphorus, and Magnesium) from Cooked Beans (Phaseolus vulgaris L.) in Growing Rats
Most of the other relevant documents were behind paywalls. Read the rest of this entry »
March 13, 2012
First, credit where credit is due. I read Mike the Mad Biologist. His post pointed me here, which mentioned an atrociously written Washington Post article (bad arithmetic, erased without comment, then corrected, with no reflection of the vastly different results in the text). This got me to think about buying efficient light bulbs as an investment, and so I did some interest calculations, as if the bulb were paying a mortgage.
I’ve long been interested in LED lighting, and have installed some myself in places where it was a clear win (underneath cabinets and on bicycles). I’ve been wary of “LED light bulbs” for some time, because to be fair, diplomatic, and objective, up till now, most of them have been overpriced crap. But last weekend or so, I was at the Home Despot, saw some LED light bulbs, read the labels, decided that it was worth my while to try one of them. I got a 14 watt bulb claiming to be the equivalent of a 75W bulb, installed it, and so far, so good — it’s bright, good color temperature, and instant-on, as expected. Lifetime is TBD; claims to have a 5 year warranty (but did I save the receipt? Whoops, need to remember to do that when I buy more), also claims to have a 25000 hour life, which is reasonable for LEDs. Also claims to be dimmable, but the reviews consistently say “no, not really, not like you’d expect”.
So, if I view this bulb as an investment, what is the rate of return? Let’s benchmark it against an incandescent bulb, since that is what the Post did. I initially decided to assume that I was saving 60 watts per bulb (15 instead of 75), running it 6 hours a day, and paying $.12/kwh for electricity (actually, I pay $.15, I just checked last month’s bill). Electricity savings come to about $1.30 per month.
Assume, also, that an incandescent bulb costs a dollar, and has a lifetime of 1500, so include the cost of the bulb in each month’s savings. At 6 hours per day, the bulb savings are 12 cents per month. Total savings are $1.42/month.
Assume the bulb will last 10 years (21600 hours at 6/day). I paid $30 for the bulb, plus sales tax, rounded up, is $32.
So, supposing I made an investment of $32, and it paid me back $1.42 per month for 120 months, at which point, no more payments, just as if I were loaning money to someone else for an itty-bitty mortgage. Spreadsheets have a “RATE” function that will determine the interest rate given a present value, future value, payment amount, and number of payments; in this case, -32, 0, 1.42, and 120. And out pops 4.4 percent. Not very exciting, though it helps that it is free of taxes, since it is money saved, not money earned. And if you only ran a bulb 3 hours a day, and only saved 45 watts, and only paid $.10 per killowatt hour, only 1.2%. That’s not much of an investment, is it?
But those interest rates are PER MONTH, not per year. So really, 1.2% — that’s 14.4% return, per year, tax free. If you return to the original assumptions, the $32 investment in an LED light bulb pays out at 52.8% per year.
What’s the risk in this investment? I see three possible risks that could cause it to fail to pay out.
First, you can only save money that you have; if you go bankrupt, then it’s not interesting that you aren’t paying money to the electric company, because you’re already not paying money to the electric company. However, all investments are vulnerable to bankruptcy risk.
Second, electricity in the next few years could become incredibly cheap (pigs could fly, too).
Third, the bulb could fail. Obviously, it pays to save your receipt; that gives you insurance of some sort for up to 5 years. If the bulb fails in five years instead of lasting ten, then the payout is not as impressive. If electricity is too cheap, or if you don’t run the bulb enough hours per day, it won’t pay out (3 hours per day, $.10/kwh, 45 watt savings, 5 years, will not pay off). But, if a bulb is on even 4 hours a day at $.10/kWH, the interest rate is 7.4%, or 3 hours at $.12/kWH, is 5%. Where I live with $.15/kWH electricity, 3 hours a day, 45 watts less, failing at 5 years, pays off at 14.8%. At 6 hours a day, 45.8%. I really like the idea of an investment that pays me 14.8% annual interest, tax-free, when it “fails”.
Did you notice that the Washington Post thought it was more important to tell you about the terrible government-subsidized light bulbs, when they could have been giving you this useful information instead? Says something about their priorities, doesn’t it? Hard to believe that anyone would think time spent reading that would be well-spent.
February 18, 2012
February 4, 2012
From a Slashdot discussion of how fast ice caps could or could not melt, this time with all the arithmetic corrected and embedded references.
Radius of earth, r = 6.4 × 106 m
Size of illuminated disk = PI × r2 = 1.3 × 1014 m2
Sunlight at top of atmosphere = 1366 W/m2
Continuous solar watts, p = 1366 W/m2 × 1.3 × 1014 m2 = 1.8 × 1017 W
Solar energy per year = p × seconds/year = 1.8 × 1017 × 3.15 × 107 = 5.6 × 1024 J
Volume of Greenland and Antarctic ice caps = 33 × 106 km3 = 33 × 1015 m3 = 33 × 1018 l
Weight of ice caps = 0.92 kg/l × 33 × 1018 l = 3 × 1019 kg
Heat to melt the ice caps = 333.55 × 103 J/kg × 3 × 1019 kg = 1 × 1025J
Years of total solar power received by earth required to melt the ice caps =
1 × 1025J / 5.6 × 1024 J = 1.8 year
And you might think, that’s a lot, right? But consider the size of the ocean: 1.3 × 109 km3, versus 3.3 × 107 km3. It takes 80 calories to melt a gram of ice, and it takes 1 calorie to heat a gram of liquid water by 1 degree C. That is, to melt all the ice (but not warm it to ocean temperature), the oceans would cool on average by (3.3 × 80)/130 = 2 degrees C.
And this is why global warming is slow, and why changes in ocean currents can produce much larger effects in the short-term. There’s an enormous amount of heat stored in the oceans.