Physics do not apply in the Star Wars universe.

I'm not just referencing Solo's "Kessel Run in less than 12 parsecs" claim, which can be explained away as a boast about navigational and piloting ability rather than ship speed. (Though there may be relativistic reasons for why speed would affect the ability to accomplish the Kessel Run in a shorter distance.)

In the latest BrickMaster (LEGO's magazine), there's a fake ad from Koensayr for the Y-Wing that claims "Goes from 0 to 2,700G in less than a parsec!" I was going to try and figure out what that meant, and then realized that 2,700G is acceleration and parsec is distance! When car manufacturers boast that a car goes from 0 to 60 in 4 seconds, what they are bragging about is acceleration, that within 4 seconds, the power is such that the car can be accelerated to 60 mph from rest. What the hell does 2,700G mean? (Besides the fact that G is meaningless in Star Wars unless it references a specific planet.) If we take G to be 10 m/s^2, then 2,700G = 27,000 m/s^2. At that acceleration, it would take about 7 seconds to accelerate to lightspeed. I'm fairly certain that's not possible in the X-Wing flightsim games. Hyperspeed, yes, STL acceleration, no way.

stats on tv

I just saw a Toyota ad on tv that claimed that 80% of Toyota vehicles sold in the last 20 years are on the road today. What this statement would like you to believe is that if you buy a Toyota now, chances are good that it will be drivable for 20 years.

What the statement actually tells you is that of the cars sold over the period 1989-2009, 80% of those cars are on the road today. However, the distribution of "hard" failures is unknown, at least just from these statistics. It could be the case that all Toyota vehicles fail at exactly the 16-year mark: if Toyota sells the same number of cars each year, then the cars that would be running today were sold between 1993 and 2009, or 16 years worth (80%) of cars.

Alternatively, it is highly likely that the number of Toyota cars being sold today is much higher than it was in 1989, so of those 80% that are running today, most might have been sold in the last 10 years or so, which might put the average lifespan closer to the early teens.

Histograms in Excel for Mac 2008

While I do have a whole 'nother post coming up about the failings of Excel 2008, one major issue that was resolved is the analysis toolpak causing Excel 2004 to crash. "Luckily", this problem is fixed by removing VBA from Excel 2008, which means there is NO analysis toolpak. Not that it was ever great to begin with, but I guess histograms are nice. Anyway, I figured people might actually want to do histograms of their own. To that end, I created an excel file that does histograms.

Some of the stuff is a bit of kludge, but I'm sure it's fairly self-explanatory: put your data in column A, and the number of points in the appropriate cell. If you need more bins, change the number of bins and adjust the chart accordingly.

Link Here

Obviously, this is intended for Excel 2008 (and 2007), but it should be backwards compatible with earlier versions, as long as you have the necessary updates to read the new file format.

You keep using that word [logic]: I do not think it means what you think it means.

From Francis Collins, who argues the following as scientific evidence for God:

An additional set of observations I found quite breathtaking and do to this day is the fact that the physical constants that determine the nature of interactions between matter and the way in which energy behaves have precisely the values they would need to have for any kind of complexity or life to occur.

I interpret the argument to be thus:
(1) the physical constants necessary to support life are extremely rare
(2) because the life exists, then God must exist.

I am skeptical that (1) is true, since we don't know ANYTHING about extraterrestrial life to say what could or could not be supported by different physical constants. It is outside our realm of knowledge to say that lifeform X could not exist under conditions Y because we don't know about all the different types of X or even all the different types of Y.

But for argument's sake, let's suppose you accept (1). Then you hit the BIG logical fallacy:

Because life exists (and the conditions to support life are astronomically rare), God must exist.

Which is completely ass-backwards, because the logical sequence of events is:

God exists => the physical constants of the universe are tuned perfectly => life exists.

Since we are alive, this statement CANNOT be disproven. It can only be disproven if we find (a) perfect tuning of physical constants of the universe and (b) the LACK of life. By definition, it would seem difficult to both determine the physical constants of the universe while not being alive and also proving that no life existed elsewhere in the universe.

This is an extremely basic logical fallacy that I learned about in 8th grade in the math unit on logic, but I'm sure I had an intuitive sense of why this was incorrect earlier than that. Claiming that this is "scientific evidence" for God is just plain BS, cuz last I checked *real* scientists (and scientists-to-be) use logic.

If only the US had this problem.

Apparently, the Netherlands are importing criminals from Belgium because there aren't enough in the Netherlands. (and Belgium is paying them a cool 30 million euros to do so.)

Hmmm, let's see, the Netherlands have 16 million people (according to Wikipedia) and 12,000 criminals in prison. That equates to about 75 detainees per 100,000 in the population.

By comparison, it is 751/100,000 in the US, or about 1% of all adults. Is crime rate actually 10 times higher in the US, or are we 10 times more likely to put people in jail for the crimes they commit (compared to the Netherlands)? My guess is that it is more of the latter than the former, given that the Netherlands has much laxer laws on drugs, which is one of the main causes for the high prison population in the US.

Unfortunately, I'm not convinced that the US will ever change on this, because there's very much a self-righteous view on punishing people for their crimes (rather than rehabilitating them to be useful to society). That, plus the prison union is pretty sizable and has an obvious interest in keeping themselves employed by supporting laws that put more people behind bars for longer.

Fisheries, Finance, and Physics

[edited for clarity]

See what I did there with the phonetic alliteration? :)

Q. What is the difference between the LHC (Large Hadron Collider) and Banks?

A. Black holes created by the LHC are more transparent about where stuff goes...



One theory about the potential dangers associated with the LHC puts the risk of it destroying the Earth at 50-50 (watch the clip!). Of course, this must be qualified by examining the probability that this theory of assessing the risk of the LHC is correct (0%). Other estimates of the risk posed by the LHC suggest that the probability of destroying the Earth is at 10^-9. As Ord, HIllerbrand, & Sandberg rightly point out, this should be qualified by the possibility that the model is incorrect or that calculation errors have been made.

In most cases, it is impossible to gauge the failure probability for something like a single bolt on the space shuttle. In these cases, mathematical models are often used. Clearly, estimates of the probability of "rare" events need to take into account the possibilities that the models used to generate such probabilities are accurate.

Andy Haldane describes a similar problem with how the financial industry assessed risk: some of the initial events that sparked the issue were "unlikely"* Well, either we are extremely "lucky" or the model is incorrect. Unless you can demonstrate to me that the probability of the latter is less likely than seeing that kind of impossible event, I'm going to bet that someone somewhere screwed up. In fact, it's plain to see from Chart 1 of the notes for Haldane's speech how this could happen. In the chart, data collected over the last 10 years (1998-2007) suggested that the probability of negative GDP growth was, effectively, zero. Looking over the whole sample of time (1857-2007) in which this data has been collected, however, suggests that negative GDP growth occurs maybe 15% of the time. That doesn't seem like a big difference, but when you bet billions of dollars on what you think is a sure thing (non-negative GDP growth), but actually occurs maybe 1 in 7 times, that's an f-ing big risk.

What does this have to do with Fisheries, you ask. Well, according to the Magnuson-Stevens Act (yep, THAT Ted Stevens), "Conservation and management measures shall be based upon the best scientific information available.". I suppose this means that fishing should not be a level where there is a significant risk of collapse. (whatever significant means...) Of course, the estimation of collapse risk is done using a model, which is fallible, possibly with high probability. If your best available science is not very good, is that sufficient to go plowing (or trawling, I guess) ahead? Your "best" model may suggest that you can fish 100,000 tons per year with < 1% chance of collapse, but if your model is only ~80% accurate (which is really good for fisheries models!), the upper bound on the probability of actual collapse is closer to 21% (0.8 * 1% + 0.2 * x, where x is unknown, but up to 1, potentially).

Logic and stats are nice when they're applied correctly, but more often than not, their use is exaggerated. And part of the blame does rest on the shoulder of scientists, who necessarily play up their results to get funding/acclaim/jobs. Still, that *is* why we have scientists advising the government, right? So that government officials will be able to take the best information available to make decisions? (and then we cross our fingers that our elected officials (or their appointees) know enough to weigh information properly...)

* shifts on the order of 25 standard deviations, which Andy calculates to occur roughly once every 10^135 years or
1000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000 years.

1) Ord, T., Hillerbrand, R., & A. Sandberg. Probing the improbable: methodological challenges for risks with low probabilities and high stakes. [preprint] (2009).

2) Haldane, A.G. Why banks failed the stress test. [speech] (http://www.bankofengland.co.uk/publications/speeches/2009/speech374.pdf) (2009).

Math in the new Terminator Show

I think I might be one of the only ones who freeze-framed the first episode of "Terminator: The Sarah Connor Chronicles" to verify the digits of pi when the flied by on a pan-through of the chemistry classroom. Ignoring for a second, why there are astronomy-related diagrams up on the wall and math constants rather than, say, the periodic table, I can tell you that the digits are probably correct. I say probably because I only know enough to verify up to the 82097 part. I used to know about 8 digits past that, but have since forgotten them. And it seems like a pretty common pi poster anyway.

Also, Summer Glau is hot:

Did I mention that she's the new "good" terminator? I almost crapped my pants when she delivered that classic line: "Come with me if you want to live."

Thank God for Fox's On-Demand Internet Streaming in not-bad high-def.

Math in Reideen

Here is a screenshot from the 4 minute mark in Reideen, a remake of the original Reideen anime from the 70's. Besides the fact that student multiplied by a binomial including a radical ONLY to resort to the quadratic formula, can you spot the error?

Also, I do not condone doing that much mental math when multiplying polynomials involving radicals. That's how you make errors. (The final answer is correct, but one of the equations is incorrect.)


I'm also somewhat disturbed by this "hint" from a friend. I hope it's a joke from the fansubbers...

Math Club...

may now be meeting twice a week. Yikes!

Yes, I'm in charge of the Preuss middle school math club. I figured since Preuss is all about academic achievement, it needed a math team, but things are so competitive at the high school level, that it really only makes sense to start with the middle-schoolers. Currently, we meet on Mondays, but now the kids want to meet on Wednesdays as well!

I guess they were finally convinced today that they need some extra work after I gave them a warmup from the MathCounts handbook and they didn't do so well. Before, I used to cover some topics I thought were interesting, but they thought I was always pitching something too difficult. (probably true) Nevertheless, the problems I was giving them were not particularly harder than what they would see at an actual MathCounts competition.

Anyway, I am currently in contact with a different teacher to see if we can use another room for Wednesdays as the current teacher who is helping us is only around after school on Mondays. Hopefully we will be able to meet two times a week. Furthermore, if I can get the average warmup score into the 6+ range (instead of the current 1.5), I am confident that the kids can be reasonably competitive at the chapter level.