xel02's comments

What happens when the US's eleven supercarriers are not in the Strait of Hormuz or floating around the Pacific. The threat is enough to guarantee countries think twice about annexing their neighbors provinces.

I.e Bob might be looking for a job and is willing to accept calls between 12pm and 1pm, but not at 3am.

Or Jane may already have enough leads and does not want to accept any calls (too busy) but normally is available between 3pm and 4pm.

I'm going to find all the students that go to schools that grade on a curve and I'm going to take the opposite side of all those short-sell bets, package it into a derivative and sell that! I'll open a bunch of firms and call it "Ivy Street".

With all these prediction markets being opened up, with film companies hedging their movie scripts, I haven't looked but there's probably a market for betting on record sales. Who bets on these things? I can understand people with an edge (insiders etc), but how can there possibly be retail investors for these markets? Are stocks, bonds, mutual funds, options, futures, ETF's not enough to speculate with?

I'm in a similar situation and I'm looking into doing a graduate degree in Operations Research (OR) or Industrial Engineering, which is usually offered either in Business schools or Engineering schools. You essentially do research on solving real-world problems with quantitative methods.

Many of the OR graduates (even those with PhD's) end up not in academia but in business. If you have more questions feel free to email me.

Wikipedia says he's one of the most highly cited people in the world.

I 'know' him better through his ideas of grammars (Chomsky Normal Forms) and their applications to bioinformatics.

The article itself is interesting, a bit wordy. Chomsky is a well known academic in the sense that his work on linguistics is seen in many places from Psychology to Computer science.

The fact that he's also anti-government is new. I liked one line from the article (towards the end of page 1): What I talk about are the liberal intellectuals, ... They tell us how far we can go. They say, ‘Look how courageous I am.’ But do not go one millimeter beyond that. At least for the educated sectors, they are the most dangerous in supporting power.

If nothing else the article is a bit thought provoking and I think most people could use a bit more thinking in their daily lives.

The book itself is approachable with a basic knowledge of mathematics, probability, and statistics. It provides a good introduction to things like Sabermetrics (for baseball), and applications to the NBA and the NFL.

Yes: it undermines income streams. In the second year, purchases fall, and in the third year there are none at all. If the second-hand market could be eliminated, books would last longer than 3 years and could be cheaper. There is a way: to produce electronic books [e-books] and kill them after a year.

That answer bothers me, a lot. Especially when in the beginning he says a textbook should be a lifelong companion.

Frankly a good textbook shouldn't HAVE a substantial secondhand market. As a student I do a lot of research into which textbooks to buy, occasionally I forego the 'required' textbook and get something that is more recognized by the industry or other academics.

I've found that if I ever buy a textbook I intend to keep it.

A good way is to look at maybe the lecture notes of an undergrad functional programming course. They usually present it quite simply.

Unfortunately the course at UBC does not post the lectures online openly but rather through a restricted CMS.

The majority of microbial species in the world cannot be cultured due to a lack of understanding in the nutritional requirements. This means microbiologists have a very difficult time studying them, one way of getting past this is studying the genetic makeup of a population.

However the best way to understand microbes is to grow them, a lot of bacteria are easy to grow (beef broth) others impossible.

Then there are ethical considerations in 'giving' people bacteria that are not well characterized.

It is a pretty well supported theory that exposure to bacteria is important for the development of the immune system, it is also pretty well accepted that the normal flora of humans is important in preventing infections.

How antibiotics, probiotics etc. affect humans are however much harder to characterize and understand.

I say this because I just read in a book (A Drunkards Walk) how seniors in a home who could arrange their rooms the way they liked and could choose a plant to take care of were measurably happier and lived longer.

Restricting machine names, removing snacks, clocking in and out these all contribute to a negative environment.

Which employee (all other things being equal) is more likely to burn out: a) Diligent and responsible employee is essentially free to do what they need to do to get their job done. b) Diligent and responsible employee who gets shuffled into a 'highschool' scenario: hall-passes, attendance reports, dress code.

Obviously some places feel they require these restrictions. Maybe in a large corporation you'll end up hiring employees who you can't trust to show up on time, etc. But isn't that also HR's fault?

Software isn't covered by the extended warranty at both places so that means regardless if you have Windows or Linux issues the tech's will not fix it under the extended warranty.

The warranty only covers hardware issues not caused by the user (i.e. spills or drops).

I've had linux laptops come in and we usually didn't bat an eye (the average tech seems to know of it and the occasional one actually uses it). We generally don't care because we run software off of a bootable disc to do diagnostics assuming the issue is a hardware one and not software.

I think one plausible reason that the netbook was rejected in this case is most netbooks do not have dvd drives and they may have had difficulty running the diagnostics.

Of course the source story paints a very hostile picture from one side. Without knowing the other side we can't know what the real issue was. It could have been that the technician legitimately believed software damaged the netbook. Or the customer could have been rude in which case the techs and manager became hostile. Who knows?

In either case he should either bring it to another store or send a letter/email to someone at head office who will almost always take care of the customer.

Of course the whole linux and damaging hardware issue is still open. I remember a while ago that there was a 'minor' bug in Ubuntu that caused the continuous strain to the hard drive that could theoretically cause damage.

We didn't use a textbook for this class but the notes are online at: https://slate.math.ubc.ca/slate/Slate/2009-2010/Winter_Term1...

I personally have both of Strang's Linear algebra books (Linear Algebra and its Applications, Introduction to Linear Algebra), there is also David C Lay's Introduction to Algebra.

My earlier course used Schaum's outline to Beginning Linear Algebra. I found that it doesn't give any reason for studying it, but if you like pure mathematics it is cheap and focuses on that aspect of linear algebra.

Linear algebra is fundamentally about solving equations and properties of systems of equations. In the course I'm taking we first showed that linear algebra has huge applications by doing a quick and shallow overview of Google PageRank. http://en.wikipedia.org/wiki/PageRank

Then we started from the beginning of linear algebra basically with a system of equations and finding their solutions. We used this idea to solve the problem of interpolation. Given a set of points how do we draw nice smooth points that connect them all, the solution that we looked at was a cubic spline. Before computers people would do this by hand using PHYSICAL 'calculators' in the form of a piece of wood/plastic that bends smoothly. http://pages.cs.wisc.edu/~deboor/draftspline.html

We then went on to cover the 'four fundamental subspaces' of a matrix. It is hard to describe but you can think of a matrix as encoding all of the information in a system of equations. The fundamental subspaces represent information about the different solutions that may or may not exist and where to find them in a 'space'. We used these ideas to look at resistor networks. One thing we modeled was the atmosphere as a very large graph all connected by resistors, we then simulated lightning as it 'traveled' through the matrix. From this we 'learned' that the atmosphere is most likely composed of elements with varying degrees of resistance since lightning is jagged shaped and not even. (Hand waving explanation there).

Then we came to the idea of orthogonality. If you remember a bit of about vectors two orthogonal vectors are vectors with a 90 degree angle between them. Using the ideas of orthogonality you can do least squares. A huge idea in statistics for linear regression, fitting a bunch of points to a straight line.

We also looked at the most awesome applied mathematical discovery the Fourier series/transform. The idea is that we can take a signal and transform it into a signal composed only of juxtaposed sin and cos waves. This is important in image analysis (i.e. medical imaging) as well as many other branches.

We then looked at eigenvalues and eigenvectors. When an matrix is applied (multiplied) to one of its corresponding eigenvector the eigenvector is only stretched or flipped. This is used in image manipulation, like properly stretching a picture without deforming it. It is the underpinning of Principle Component Analysis, a statistical technique to take data that has high-dimension (i.e. a lot of different measurements) to find the main directions where the measurements change.

I am personally doing research with a group using eigenvectors and eigenvalues to build algorithms that can be used to classify observations from a flow cytometer to differentiate between cells with or without cancer or hiv.

In my personal opinion linear algebra is just as important if not more so than calculus. Almost every aspect of modern analytical research needs the use of linear algebra as we are dealing with large amounts of information that must be manipulated with computers. This is when linear algebra is at its best (in my opinion).

Hope that answers some of your questions. Please do not take everything I've said as perfect or accurate, like I said I haven't done my final in the course yet, nor am I a mathematician. But I do hope that it shows that linear algebra has wide applications from basic cell research to how you get your daily dose of information.

Parents always think that they should keep their children super clean etc. but the natural development of the immune system requires some exposure to pathogens.

For example the hygiene hypothesis: http://en.wikipedia.org/wiki/Hygiene_hypothesis

Superbugs like MRSA are predominantly found at hospitals causing nosicomial infections as well as in populations with bad hygiene like the homeless. This device is probably best used in those areas.

In terms of frequent use by the general population I think we need to be a bit careful. That said I would probably get one just to say I've got a super plasma germ killer.

I can't seem to find too much details on how it might work other than the fact that it looks at a specific region of DNA that is common between a lot of eukaryotic species.

For example in probability the St. Petersburg paradox. http://en.wikipedia.org/wiki/St._Petersburg_paradox