Category: Numbers & Statistics

Innumeracy

Numbers & Statistics

Oh FFS.  This simple question has apparently caused all sorts of mayhem among the innumerate:

The answer is of course “FALSE” — and to think otherwise is to be ignorant of two of the simplest definitions in mathematics, i.e.

  • “A right angle is defined as two straight lines meeting at a 90-degree angle”, and
  • “There are no straight lines in the circumference of a circle.”

And in the above picture, there’s only one straight line.

That anyone can even be fooled by the question means that math education has been completely screwed up.  I agree that it’s quite a tough question for a seven-year-old child (as posed in the article), but nobody with more than a seventh-grade education should be stumped by it, let alone a professor of mathematics.

By the way, ignore the red herring that a straight line consists of two right angles:  that’s only a partial definition of straight line.  (“The shortest linear distance between two points” contains only implied angles, not actual ones.)

And by the way:  the correct spelling is “two right angles”, no hyphen necessary.

I need another gin.

Update:  Oh FFS-squared.

For the above diagram to contain two right angles, one would have to add a third radius, thus:

Now the question “There are two right angles” has the answer “True”  (A0C, B0C).  If you were to answer “False”, giving “because there are four right angles” as your reasoning, you would (rightly) be given an “Incorrect” because there are only four right angles in the imaginary world (i.e. Thales’ Theorem et al.).  However, we are not in an imaginary world because we are not talking concepts, we are talking about an actual diagram.  And to cap it all, we are talking about a question posed to a seven-year-old child, for whom Thales has no existence.

As I explained to a Reader in an email on this very topic, it always pays to remember that mathematics has little basis in reality, e.g. where a line can have direction but no thickness and a point has a position but no size.  And I’m not even going to touch on division by zero… [eyecross]

Quote Of The Day

Numbers & Statistics, QOTD

From Taki’s Magazine:

If there are two categories in which black people outperform nearly everyone else on the planet, those would be sporting events and crime.

Our modern era is no different from other ones, despite our pretensions at civilization.  You can get pilloried, accused and even arrested just for speaking the truth.

Galileo would understand exactly what I’m saying.

Jackals Of The Press #1,254

Media Assholes, Numbers & Statistics

I know, I know:  if you want fair and balanced reporting, don’t read Britain’s Daily Mail.  Yet I persist, despite nonsense like this, because I am weak.

This particular article starts off well, showing people getting their last kicks in before the latest totalitarian bollocks from H.M. Government, in the usual Daily Mail  fashion:

 

All well and good, and nothing puts me in a good mood like Train Smash Women (like I said, I am so weak).

However, the DM then eschews standard journalistic principle — I know, I know — and turns a general-interest piece into a study of the Chinkvirus re-emergence in Britishland.  For reasons best known to themselves, they publish some scawwwwy-looking graphs with the usual crap predictions from Doom & Gloom Inc.:

…although they do have the grace to give some actual numbers:

…which of course shows that even though hospitalizations are increasing, the death rate (which is the important number) isn’t doing anything alarming.

But non-alarms don’t boost readership, so the JOTP publish two graphs which show how scawwwy things could get, only they use Spain and France — no doubt because those two countries’ experience bolsters the alarmism:

Of course, what gives this bullshit away is the way the graphs are scaled.  Note that the right-hand graph (of daily fatalities) has a very fine scale, which despite the steep climb, simply means that the Spanish fatality rate has gone from much less than 1 to just over 2 deaths per million population  (0.2 per hundred thousand = 2 per million), while the Frogs have gone from pretty much zero to 5 per ten million.

I don’t have access to those countries’ accident stats, but I imagine that 2 per million and 5 per 10 million respectively are rather less than the death rates from, oh, falling down stairs or drowning in a bucket of wine.

So the DM took a perfectly okay article about people getting their last unfettered drinks in, and added all that pseudo-scientific bullshit.  Of course, those are really subjects for two different articles (one of the prime journo principles being:  don’t try to tell two stories in a single article).

Were it not for daily pics of the skinny Amanda Holden and the not-so-skinny Kelly Brook, I’d give them up altogether.

 

But did I already mention how weak I am?

Headache

Good Stuff, Numbers & Statistics

Just when I thought I’d figured it all out, comes shit like this:

‘They are the sort of equations that arise when you try to study something that evolves in time but also depends on space.
‘For example, like the wind in a wind tunnel you want to model the flow of air then that of course depends on time because it changes over time but it also depends on space – the velocity of the air is different at different points in the wind tunnel.
‘So if you have a system like this which furthermore evolves under the influence of randomness.
‘So if you have randomness that enters the game then that’s described by stochastic partial differential equation.’

I used to work with people like this when designing predictive algorithms, and I would place bets with myself as to how long (measured in seconds) it would take before I lost track of the conversation completely and the speech became unintelligible.  Usually, it was about twenty seconds.

It gets worse.  The reason I used “20 seconds” in the above sentence is because I actually kept count, over the year’s worth of discussions and meetings, of the times.  Then I created a distribution chart — bell-shaped, of course, with the most common incidence around 20.

Yeah, I was a fucking geek, too.  Just a much more limited one.

By the way, if you read the article — and you should — there’s a glaring (but non-mathematical) error.  Call it the Obama Fallacy, and see if you can spot it.

Calling Bollocks

Drive Time, Lies and Untruths, Numbers & Statistics

Here’s an example of “studies” that just set my hair on fire:

The LEAST reliable used cars revealed
Warrantywise has published data from its Reliability Index for older cars
A minimum of 100 examples of each car is needed to provide a reliability score

…but here’s where the turd hits the punchbowl:

It measures reliability based on the volume and cost of repairs to vehicles

Including cost of repairs means that.. wait for it… cars like Bentley and Audi are going to fall to the bottom of the list, regardless.

Here’s the scenario:

  • one of their “reliable” cars (e.g. the Dacia Sendero, a complete POS) may have ten problems after its warranty expires, but because the average cost of repair is $100 (Dacias being made of plastic and scrap metal), its score comes to 1000
  • an Audi A7 breaks down only twice, but its average cost of repair is $1,500 (because when quality stuff does break, it’s expensive to fix), giving it a score of 3000 — so the Audi is three times less “reliable” than the Dacia, according to the study.

But in terms of actual (instead of cost-weighted) reliability, your Dacia was in the shop ten times, compared to the Audi’s twice.

I’m not saying that’s what happened in the study (I don’t have access to the raw data), but that’s the problem when you add irrelevant factors to an equation.

The real problem lies with the title.  If Warrantywise had called their study “Total Cost Of Post-Warranty Ownership”, it would have given the output a better foundation.

Or if they were going to stick with reliability, they should have ignored cost and instead stressed weighting factors of “frequency of breakdown” and “magnitude of failure” (brake lights fail, no big deal;  transmission dies, much more serious).  That, at least, would have given prospective buyers a clue.

All that said, I’d still get one of these (with only 12,000 miles usage)

…over a poxy Mitsubishi anything.

(See what I did there?  About the same thing as Warrantywise did.  It’s called “bias”.)

Anyway:  if you can afford to buy it, you should be able to afford to maintain it.

And can ignore silly studies.

Bad Stats

Lies and Untruths, Numbers & Statistics

Back when I worked for the Great Big Research Company in Johannesburg, I had a boss who had the unnerving habit of doing random checks on my calculations.  (I should point out for my Readers who were born after we discovered the wheel that computations were done not with slide rules but with the newfangled invention called a “calculator” — which could do only the basic math functions of addition, subtraction, multiplication and division — and the literally thousands of numbers were taken off pages and pages of computer printouts from a thing called a “mainframe”.)

Anyway, if the Poison Dwarf (as we not-so-jokingly called him) discovered a single mistake, he would tear it all up and make me redo the entire job, with the rationale that “If I can’t trust one thing, I can’t trust anything.”  The result, after only a couple of these episodes, was that I not only took an inordinate amount of time in performing the calculations, but spent almost as much time rechecking everything to make sure that absolutely every statistic or number I presented to my clients was 100% correct, and they could take the actions I recommended with complete confidence in the strength of the data.

The time spent in doing all this was based on another of the Poison Dwarf’s aphorisms:  “There’s never enough time to do the job properly, but there always seems to be enough time to do things over.”  Well, I never had enough time to do things over — I had client meeting deadlines — so I had to get it right the first time, regardless of the time taken.

That habit persisted with me for the rest of my working career.

I say all this so everyone will know exactly where I stand on bullshit like this (with emphasis added):

A young Florida resident who died in a motorcycle accident is included in the state’s official COVID-19 death count, a state official reveals.
FOX 35 News in Orlando discovered this after asking Orange County Health Officer Dr. Raul Pino about two young COVID-19 patients in their twenties who died, and whether they had any preexisting conditions that contributed to their deaths.
“The first one didn’t have any. He died in a motorcycle accident,” Pino said. Despite this shocking answer, Pino was not aware of this person’s data being removed from the state tally when asked.
“I don’t think so. I have to double-check,” Pino answered. “We were arguing, discussing, or trying to argue with the state. Not because of the numbers — it’s 100… it doesn’t make any difference if it’s 99 — but the fact that the individual didn’t die from COVID-19… died in the crash.”

You stupid fucking quack.  It’s not whether it makes a difference between 99 and 100 — it’s how many more mistakes of this kind have occurred in your compilation of the data.

Remember the Poison Dwarf:  “If I can’t trust one thing, I can’t trust anything.” 

So if one death (1%, in this case) was incorrectly attributed to the Chinkvirus, how many more cases are incorrect?  10%?  20%?  90%?  We don’t know, because the numbers were obviously not checked after being submitted.

Here’s something from Powerline which makes the same case quite succinctly:

Funny, but not so funny.

Here’s the thing.  A lot of decisions, very weighty and momentous decisions, are being made based on the data our much-vaunted medical establishment is presenting.  States’ economies are being damaged or destroyed, people’s livelihoods ditto, and I’m not even going to start to estimate the social cost of foolish governmental decisions taken on the basis of what may turn out to be fatally-flawed data.

So I’m going to mimic the Poison Dwarf (for the first time ever):  I’m not going to trust a single fucking piece of data these assholes present to us, ever again.  As far as I’m concerned, it’s all lies and bullshit, and I don’t trust any of them.