Category: Science
The household economics of 3-D printers
I have been a skeptic about the import of this new technology, but I am happy to pass along estimates to the contrary. This is from a new paper by Wittbrodt, et.al.:
The recent development of open-source 3-D printers makes scaling of distributed additive-based manufacturing of high-value objects technically feasible. These self-replicating rapid prototypers (RepRaps) can manufacture approximately half of their own parts from sequential fused deposition of polymer feed stocks. RepRaps have been proposed and demonstrated to be useful for conventional prototyping and engineering, customizing scientific equipment, and appropriate technology-related manufacturing for sustainable development. However, in order for this technology to proliferate like 2-D electronic printers have, it must be economically viable for a typical household. This study reports on the life-cycle economic analysis (LCEA) of RepRap technology for an average U.S. household. A new low-cost RepRap is described and the costs of materials and time to construct it are quantified. The economic costs of a selection of twenty open-source printable designs (representing less than 0.04% of those available), are typical of products that a household might purchase, are quantified for print time, energy, and filament consumption and compared to low and high Internet market prices for similar products without shipping costs. The results show that even making the extremely conservative assumption that the household would only use the printer to make the selected twenty products a year the avoided purchase cost savings would range from about $300 to $2000/year. Assuming the 25 hours of necessary printing for the selected products is evenly distributed throughout the year these savings provide a simple payback time for the RepRap in 4 months to 2 years and provide an ROI between>200% and >40%. As both upgrades and the components that are most likely to wear out in the RepRap can be printed and thus the lifetime of the distributing manufacturing can be substantially increased the unavoidable conclusion from this study is that the RepRap is an economically attractive investment for the average U.S. household already. It appears clear that as RepRaps improve in reliability, continue to decline in cost and both the number and assumed utility of open-source designs continues growing exponentially, open-source 3-D printers will become a mass-market mechatronic device.
I don’t see the twenty products a year as coming true, given the current limitations of the printers, plus there are significant start-up costs for learning how to run and fix the printers. I still despair at the paper printer we own, which breaks periodically in a non-transparent manner. What does it cost to have a plumber remove a simple hair stoppage in a drain these days? And how much does one have to pay for the IP rights for what one prints?
Still, I am happy to reproduce one economic case for the import of the technology.
For the pointer I thank Sami Varma.
What are the major market indices for climate change?
Dan Kahan asks me that question. The Credit Suisse index does not seem very liquid and it is not clear to me if it is still actively traded. In any case this earlier look at the index implies it is about mitigation efforts, not the extent of warming or climate change per se. UBS launched an index in 2007, but I don’t see recent activity in the index mentioned in Google. There are various anecdotal accounts of insurance companies being less willing to cover waterfront property in hurricane-prone areas.
I hit some walls on this one and so I turn it over to you, MR readers. What are the best market indices — of whatever nature — for tracking the extent of the problem? I thank you in advance for your assistance.
Off-label prescribing vs. RCT
Incidentally, another thing that’s fascinating to me is that, there’s a very funny saying when it comes to the ethical review of science, or an anecdote, which is that if a doctor wakes up in the morning and decides that, for the next 100 patients with cancer that he or she sees that have this condition, he’s going to treat them all with this new drug because he thinks that drug works, he can do that. He doesn’t need to get anyone’s permission. He can use any drug “off-label” he wants when, in his judgment, it is helpful to the patient. He’ll talk to the patient. He needs to get the patient’s consent. He can’t administer the drug without the patient knowing. But, he can say to the patient, “I recommend that you do this,” and he can make this recommendation to every one of the next 100 patients he sees.
If, on the other hand, the doctor is more humble, and more judicious, and says “you know, I’m not sure that this drug works, I’m going to only give it to half of the next 100 patients I see,” then he needs to get IRB approval, because that’s research. So even though he’s giving it to fewer patients, now there’s more review.
That is from Nicholas A. Christakis, via Jim Olds. The discussion is mostly about Big Data.
What is the implied model behind assortative mating?
In a fascinating new paper by Brant, et.al. on IQ, I read the following bit:
…we found that higher-IQ parents actually showed less assortative mating: the difference between parental IQ scores was positively correlated with mean parental IQ score.
My questions are numerous but I will start with two.
First, is this the correct metric for “less” assortative mating?
Second, do “straightforward” models predict such a result as a matter of course? For instance, higher-IQ individuals may have greater scope to choose mates on the basis of complementary skills. That may imply higher IQ gaps. Furthermore higher-IQ individuals may marry later in life, put more effort into choosing, and encounter a wider variety of potential partners. That may also imply wider gaps in IQ across partners, even if assortative mating (as defined in an all things considered way) remains strong.
Very often there is more variability at the tops of distributions rather than at the bottoms or in the middles. Yet “pull away” forces may continue to operate.
To present a simple analogy, income gaps between marrying couples are probably higher at the upper end of the distribution than at the lower end. Yet assortative mating with respect to income still may reenforce income inequality.
Sentence of the Day
By the fall of 2009, toward the end of Barack Obama’s first year as president, the Air Force was training more drone-joystick pilots than airplane-cockpit pilots.
From Fred Kaplan’s The World as Free-Fire Zone.
How big is your chance of dying in an ordinary day?
A Micromort can also be compared to a form of imaginary Russian roulette in which 20 coins are thrown in the air: if they all come down heads, the subject is executed. That is about the same odds as the 1-in-a-million chance that we describe as the average everyday dose of acute fatal risk.
That is from Michael Blastland and David Spiegelhalter, The Norm Chronicles: Stories and Numbers About Danger, which is an interesting book about the proper framing and communication of risk.
Is there a Flynn effect for dementia?
It seems so:
A new study has found that dementia rates among people 65 and older in England and Wales have plummeted by 25 percent over the past two decades, to 6.2 percent from 8.3 percent, the strongest evidence yet of a trend some experts had hoped would materialize.
Another recent study, conducted in Denmark, found that people in their 90s who were given a standard test of mental ability in 2010 scored substantially better than people who reached their 90s a decade earlier. Nearly one-quarter of those assessed in 2010 scored at the highest level, a rate twice that of those tested in 1998. The percentage severely impaired fell to 17 percent from 22 percent.
From Gina Kolata, there is more here.
The culture that is Japan markets in everything Newcomb’s paradox edition
In Japan, where palm reading remains one of the most popular means of fortune-telling, some people have figured out a way to change their fate. It’s a simple idea: change your palm, change the reading, and change your future. All you need is a competent plastic surgeon with an electric scalpel who has a basic knowledge of palmistry. Or you can draw the lines on your hand with a marker and let him work the magic you want.
The story is here, hat tip goes to Robert Martinez. There are some other interesting points in the article, but I shall not reproduce them here.
China estimate of the day
A government policy to promote coal use in Northern China has cut the life expectancy of some 500 million people by more than five years, on average.
That comes from a big new study in the Proceedings of the National Academies of Sciences, which used a quasi-natural experiment to quantify the health effects of air pollution from coal use.
From Brad Plumer, here is more.
Equip your robot with a Harris Tweed jacket
Robots are to be placed into the homes of people with dementia as part of a pilot on the Western Isles, but it is just one of many uses machines are being put to in Scotland amid a wider debate on robotics.
NHS Western Isles is the first health board in Scotland to try out Giraff.
The 1.5m (4ft 11in) tall, wheeled robots have a TV screen instead of a head.
A relative or carer can call up the Giraff with a computer from any location. Their face will appear on the screen allowing them to chat to the other person.
The operator can also drive the robot around the house to check that medication is being taken and that food is being eaten.
There is more here.
Two excellent new books on the history of technology
1. David Arnold, Everyday Technology: Machines and the Making of India’s Modernity. The typewriter and the bicycle revolutionized India early in the twentieth century
2. Ernest Freeberg, The Age of Edison: Electric Light and the Invention of Modern America. Two of the takeaways from this book are a) the United States had a more statist approach to electricity infrastructure than did most of Europe, and to its advantage, and b) we didn’t let lots of people accidentally being electrocuted stop progress, again probably to our advantage.
Our forthcoming labor market problem, in a nutshell
It seems the Israeli Electric Corp. will offer “kosher electricity” by 2014. That means (in addition to other factors) automation of the major power stations on Saturdays, with some non-Jewish workers to oversee the automation. The practice eventually may spread to weekdays too.
Do note:
And of course this will all be subject to the religious supervision of the Scientific-Technological Halacha Institute.
For the pointer I thank Mark Thorson.
Claims about me
Tyler Cowan [sic] wishes he could be teleported to Kansas or Korea or the moon to live in a Gucci-free egalitopia.
That is from George Gilder’s new Knowledge and Power: The Information Theory of Capitalism and How it is Revolutionizing Our World. reviewed by Arnold Kling here.
Now that is a claim I would be willing to bet on.
How to curb climate change?
Paying Canadians to keep their oil sands in the ground to curb climate change might not sound like an obvious vote winner to a cash-strapped European government.
But it makes more economic sense than people realise, according to Bård Harstad, a Norwegian academic who has just won a prestigious environmental economics prize for a provocative paper suggesting just such a move.
Mr Harstad, 40, has been awarded the Erik Kempe prize, worth SKr100,000, by the European Association of Environmental and Resource Economists for a study called “Buy Coal! A Case for Supply-Side Environmental Policy”.
The FT article is here, and you may recall an earlier MR suggestion that sealing or blowing up especially dirty fuel sources, in a Hotelling intertemporal resource extraction model, is more likely to be effective than many kinds of tax.
Why are there not more science majors?
There is a new paper (pdf) by Ralph Stinebrickner and Todd R. Stinebrickner on this topic, and here is their bottom line conclusion:
We find that students enter school quite optimistic/interested about obtaining a science degree, but that relatively few students end up graduating with a science degree. The substantial overoptimism about completing a degree in science can be attributed largely to students beginning school with misperceptions about their ability to perform well academically in science.