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Comment: Re:Neandertals and light skin (Score 2) 133

by Michael Woodhams (#47374319) Attached to: Tibetans Inherited High-Altitude Gene From Ancient Human

Immune system genes are often under balancing selection - i.e. the rarest alleles are favoured (until, due to this favouring, they cease to be rarest, then other alleles are favoured.) An infusion of new different alleles from Neandertals could be favoured simply because they are different, not because they are evolved to European conditions.

Testing between these hypotheses seems difficult. The 'balancing selection' hypothesis predicts that the genes will readily spread back into Africa, whereas the 'evolved for European conditions' predicts they will not. The problem is that you need some neutral mutations that arose in Europe at the same time as a 'control' for comparison purposes. I'm not sure how to identify such mutations, but I expect it could be done.

Comment: Neandertals and light skin (Score 3, Interesting) 133

by Michael Woodhams (#47374055) Attached to: Tibetans Inherited High-Altitude Gene From Ancient Human

There is another obvious point in history where such a gene transfer could have occurred. European conditions favour light skin, and Neandertals had been hanging out there for some tens of thousands of years before modern humans turned up and so had evolved light skin. These newcomers, having recent ancestry in Africa, were probably dark skinned. Interbreeding could easily have introduced the beneficial-to-European-conditions light skin mutations into the modern population.

My memory of the literature (which I have followed just a little bit, not closely) is that this did not happen - genetic analysis shows that modern Europeans and Neandertals acquired light skin through different mutations. However, Wikipedia says this is still under debate.

Comment: Re:Careful (Score 2) 116

by Michael Woodhams (#47365287) Attached to: Renewable Energy Saves Fortune 100 Companies $1.1B Annually

This is a silly objection. That isn't how payback times are used.

Payback time is a quick indication of return on investment. You then compare that return on investment with the other options available to you, such as leaving the money in the bank.

If you included interest rates in payback time, you'd need to be constantly adjusting it as rates changed, and it would differ for different entities depending on their access to finance. Instead you keep it simple, and each entity has its own idea (based on circumstances and current interest rates) of what the effective payback time is of leaving the money in the bank (or not borrowing it, or investing it in other opportunities.) (For example, a start-up is likely to require a very short payback time - they're strapped for cash and are trying to get their Big New Idea to market where they hope it will make a fortune. Up-front money is then very expensive compared to down-the-road money. For them, it may make sense to lease a supercomputer even if buying it would have a two year payback time.)

What is missing from this analysis is depreciation of assets. After 6.4 years, money in the bank will have depreciated much less than the solar cells. Payback time is a rough guide - it tells you whether it is worth your while doing a more detailed analysis including finance cost, depreciation, tax implications etc.

Comment: Re:Show me the money! (Score 4, Insightful) 441

They aren't. They're using an established term "energy payback". The authors wrote an analysis which will be useful to many people but used the word "payback" in a way which does not match your preconceived notion of how it should be used. For this, you label them "charlatans".

So all the people interested in energy payback times should not be able to publish or read about it because you've claimed ownership of the word "payback" and won't license them to use it? They should use a less clear term to express their meaning because otherwise some random idiot who reads technical papers might make the leap "payback = money", despite the term "energy payback" being self explanatory?

Had you argued that because this is "energy payback" rather than financial payback, it isn't worthy of being reported on Slashdot, I could respect your argument. Instead you label people charlatans because what they discuss is not what you're interested it.

Comment: Re:Who is that? (Score 4, Insightful) 268

by Michael Woodhams (#47312961) Attached to: Wikipedia Editors Hit With $10 Million Defamation Suit

Oh good, I'll just print up a bunch of fliers saying you torture kittens and set fire to orphanages and post them around your home town. Because nobody has heard of you and I'm not a publicly listed company, it will be 'opinion' rather than 'libel'.

I have no idea whether this guy's claims are justified, but neither do you. My liking Wikipedia does not therefore mean that the facts or the law are on the side of Wikipedia.

Comment: Prediction (Score 4, Insightful) 547

When El Nino leads to a new record high temperature by a large margin (for argument's sake, in 2015), the denialists will quietly adopt this as their new standard for 'normal' and in 2025 they'll be saying "warming is a hoax because temperatures haven't risen on average since 2015."

Comment: Re:Not the right way anyway (Score 1) 583

by Michael Woodhams (#47105723) Attached to: Google Unveils Self-Driving Car With No Steering Wheel

How about a detachable luggage compartment (boot/trunk)? You don't own the car, but you have your own luggage compartment in which you keep your miscellaneous crud. Call a car, attach your compartment, drive to the mall, detach compartment, shop and fill compartment, call another car, go home, detach, unpack at your leisure while the car goes on its next mission.

Comment: Re:No steering wheel? No deal. (Score 3, Interesting) 583

by Michael Woodhams (#47105627) Attached to: Google Unveils Self-Driving Car With No Steering Wheel

If you drive on the same streets that I do, you trust me with your safety. As my driving skills are below median, this should be a lot more worrying to you then the prospect of being in a computer-driven car. (Fortunately for you, surveys show that below-median drivers are rare.)

Comment: Re:Interesting facts (Score 2) 129

You seem to be under the impression that Eratosthenes measured the size of the Earth more accurately than the 18th century scientists on whose work the metre was based. If so, you are wrong.

We don't know for sure how accurate Eratosthenes measurement was, because we don't know for sure how big the 'stadia' he measured in were, but probably he was out by 16%. His method had systematic errors in it which would prevent a highly accurate measurement.

By contrast, scientists had been able to measure the non-sphericity of the Earth prior to the definition of the metre, which is a 0.5% effect.

From Wikipedia: "The circumference of the Earth through the poles is therefore slightly more than forty million metres (40,007,863 m)"
which indicates a 0.02% error in the original definition of the metre.

"An open mind has but one disadvantage: it collects dirt." -- a saying at RPI