The example was a little clunky, but I don't find it misleading. A biplot of two normalized variables is elliptical, if the variables are correlated. This particular hand-drawn example does indeed look a bit weird, but that doesn't detract from the main point. It clearly shows the relationship between the original data and the ordination; it's a rigid rotation.
This is easily grasped with a 2d example, despite the fact that PCA makes no sense with only two variables.
Each variable is standardized to mean = 0, standard deviation =1. If you reject this as arbitrary, you are rejecting correlation analysis as a whole - this is exactly the same standardization done to two variables in bivariate correlation, extended to a multivariate data set.
PCA is a form of (or at least related to) correlation. With standardization the resulting transformation hihlights variables in the original data that are most highly correlated. Without standardization you're visualizing covariation. Unlike correlation, covariation is influenced by the magnitude of the variables.
By standardizing, you control for differences in the magnitude of the variables, and focus on their inherent variation instead.
> we can't determine if a computed result is actually a sought result or its reflection/negative
That's not how I'd explain it. The 'sought result' and its reflection are not two different things. They are the same thing, differing only in a trivial detail of orientation. The 'negative' of the result conveys exactly the same information as the result.
I can't understand how Americans, who have the least efficient, most expensive health care system in the world, are so quick to write off public healthcare. The idea that government healthcare is more wasteful than a private system is not supported by facts, but the theory is too hard to let go of.
Which is not to say there is a perfect solution. But just about any of the alternatives would be better than the US system.
This is truly a wonderful story. But it makes you wonder how many others in a similar situation weren't so fortunate.
I lived in the US for two years, and I never understood the aversion to government healthcare. The Canadian system is far from perfect, and I know there are failures. But it's still a lot better than soliciting for online charity on a case by case basis.
I'm impressed and humbled that it worked in this case. Just a little disturbed that it was necessary at all.
I expect quinoa will be selected for environmental tolerance first. Given how difficult it is to grow in th US, top priority would be getting consistent high yield in North American conditions. Breeding has to meet the farmer's needs before you start considering the consumer.
True, to a point. Debunking one of these in a class is a good exercise. Preparing a lesson takes time, though, especially when you have to respond to something out of the blue. You could easily get caught spending all your limited spare time discussing why these theories aren't science, instead of the ones that are. Evolution is a big topic, and I'd rather spend my limited time dealing with the substantive bits.
This bothers me as a former professor, because these fringe ideas undermine teaching and waste time. Imagine trying to present a lesson on evolution, and one of your students brings this up. You spend a few minutes discussing it. Of course, you've never heard of it before, because it's beyond implausible. So you spend your evening looking into it, and the holes in the theory. Next class you spend more time discussing it. If you're good, the student understands and you move on. If not the student leaves thinking this is a valid alternative viewpoint. And no, an idea does not become valid simply because it's not impossible. It's not unreasonable to demand more than a faint hope probability before judging an idea worth serious discussion.
This happens once, and you can make it a teachable moment. But when the scenario starts to repeat itself it undermines the effort you're putting into teaching real science.
1 people think hybrids are sterile, but they're not
2 people think hybrids don't occur in nature, but they do
3 people think only plants hybridize, but animals do to
From this basis, he concludes that a chimp-pig hybrid is plausible, and proceeds to lay out his theory.
The problem is the three facts he starts with are trivial compared to the obstacles raised by PZ Meyer. To take just one, there is the difference in chromosome number. In most cases, if a human ends up with the wrong number of chromosomes, it's a lethal condition. Or you end up with Down's syndrome. With one extra chromosome. The hybrid this guy posits has a dad with 38 chromosomes and a mom with 48.
I could argue that that's not a big deal. In the plant groups I study stranger things happen. But that's in plants. Primates, as I understand it, are much more sensitive to chromosomal abnormalities.
There are many logical, evidential reasons to discount this hypothesis. Again, check out the pz meyer post linked elsewhere. Claiming I don't understand evolution because "given enough tries anything is possible" is facile. Of course anything is possible. But what is probable here?
This. The author makes the absurd claim that because many hybrids are fertile, any hybrid could be fertile. Using hybridization between two closely related birds to support the notion that pigs and apes could breed is ridiculous.
The thing I find most depressing about these crackpots is that some otherwise productive scientist has to spend an evening debunking their nonsense. And it still doesn't stop.
I taught evolution for undergrads, and occasionally had to deal with these issues from students. It takes time to look into them, and no matter how thoroughly debunked the theory, some kids find them too irresistible to let go of. It undermines real education in the end.
This is silly. Debian also provides rolling releases, testing and unstable. The release cycle is slow only if you ignore the constant development of Debian Sid.
This was hard for me to read. I spent four years waiting to adopt a child.Did almost a year of training and home visits, then waited. And waited. Why does it take so long? Because we selfishly insisted that we'd only take one ortwo children. The social workers were not subtle in letting us know that we were selfish to not want a sibling group of 4 or 5(?!) kids all at once. They made it absolutely clear that we could not expect to have a newborn, and a child under 8 was unlikely.
So to hear that, on a hunch, a judge can give a newborn to a couple that had expressed no previous interest in having kids, wtf. It's a nice story, and I'm glad that it worked out so well for everyone. But for me it really underlines how fucked up the system really is.
> There's no such thing these days as a real musician, Dave was part of a dying breed of people who got into music because they love what they do, not because they want to be famous or rich like modern day musicians.
I think that says more about you than the state of modern musicians. There will always be 'real musicians', motivated by their love of the art. Whether or not we can find them depends on how willing we are to dig past the shallow acts that top the charts.
I don't know what this has to do with bayes vs frequentist. I am not arguing that the data do not have a probabilty distribution. I am arguing that it is better to show all the data when possible, rather than an eye-catching but lossy summary.
This is easily grasped with a 2d example, despite the fact that PCA makes no sense with only two variables.