My wife, father-in-law and I were playing a board game with my brother-in-law. In this game, we were playing as detectives who have to try to find his character, but each turn he could move in secret in one of several directions. We were a few turns in at one point and he could have been in any of dozens of places at this point. We drove him nuts by saying "he's either in this spot or he's not, it's a 50-50 chance." He kept arguing "I could be in a ton of places! It's not a 50-50 chance!" But we just kept pretending we didn't understand and arguing that there were only two possibilities, he's there or he's not, so it was clearly a 50-50 chance. He got quite angry.
Either that or you buried the lede by failing to mention something rather significant about the hidden character, and you were playing Fury of Dracula. Or my boardgamegeek-fu isn't as strong as I hoped.
Very weird fun fact about arrows/darts and statistics, theres 0% chance of hitting an exact bullseye. You can hit it its possible to throw a perfect bullseye. It just has a probability of zero when mathematically analyzed due to being an infinitesimally small point. Sound like I'm making shit up? Here's the sauce
How can an outcome both be entirely possible and have 0% probability?
Key word here is "infinitesimally." Of course if you're calculating the odds of hitting something infinitesimally small you're going to get 0. That's just the nature of infinities. It is impossible to hit an infinitesimally small point, but that's not what a human considers to be a "perfect bullseye." There's no paradox here.
The thing with that is that it's actually a useful generalization to make in a lot of scenarios.
If you know nothing about the distinction between two possible outcomes, treating them as equally likely is a helpful tool to continue with the back of the envelope guess. Knowing this path needs 5 coin tosses to go right and this one needs 10 is helpful to approximate which is better.
Your example is obviously outside the realm where you have zero information, so uniform distribution is no longer the reasonable default. But the idea is from a reasonable technique, taken to extremes by someone who doesn't fully get it.
That's not even a stat question, it is a english question. It is an increase by 80% not to 80%
Statistics only come to play to figure out our new chances.
I'm not an expert either and your second option is definitly clearer than mine but I believe the % symbol doesn't have the meaning of percentage point.
It is better to make things easier for people to understand but people should also make the effort of properly reading even when it is not fully dumbed down. These are prepositions, so basic english not scientist jargon.
"By 80 percentage points" means add 80 more points to a number of percentage points, so 5% becomes 85%. "By 80 percent" means add 80 percent of the current value.
In game design, it has to be stated whether it’s multiplicative or additive. Sometimes a logarithmic function is used as well, with increases in efficiency as 1 / ( 1 + bonus ). This allows you to always add more bonus, but there’s diminishing returns.
i wish it was more common to also indicate the precedence of a percentage increase, so that it’s easier to know if i’m dealing with (x + y ) * z or x + (y * z). although that’s admittedly a lot harder to communicate.
Just include a glossary of formulas for figuring out stats/chances/whatever in your game. With clearly labeled variables. Then throw a reference to that glossary in your tooltips/helpful popups.
×25% gives you 1/4 the original value, whereas +100% is double the original value, let's say 8/4 to keep it consistent. ×125% (in case a 1 is missing) is still only 5/4 the original value.
In video games they commonly use that to mean they are multiplying by 25. We know it's not correct in stats. This is why game wikis commonly put the actual formula for things rather than the tooltip the developers wrote.
When my son was about to be born my mother in law caught wind that we didn't plan on circumcising (before researching it I mostly felt it was just strange to do cosmetic surgery on a newborn) but her argument was mostly parroting the 50% reduction in this that and the other disease, missing the fact that it was going from a 0.5% chance to a 0.25% chance, but of course introduced new risks by nature of being a surgery.
Naturally after looking more into it I learned just how bonkers circumcision is so I was far more cemented in my position
it baffles me that anyone with a penis, or really anyone who knows what a penis actually is, would think it's a good idea
would people remove a child's eyelids? NO OF COURSE NOT holy shit
piercing flesh is generally to be avoided unless absolutely necessary, as is helpfully indicated to us by it being fucking painful
The fact that it is even allowed in so-called civilized countries is outrageous. In the US it common because some religious nut was obsessed with children's masturbation.
I've always thought of math as a language and I talk to my kids about it that way too.
Math is an other way to describe the world.
It's very different from spoken languages and translating between the two needs to be learned and practiced.
Our math education doesn't include enough word problems and it should be bi-directional. In addition to teaching students how to write equations based of sentences we should teach them how to describe what's going on in an equation.
Yeah, it is kinda both in general. Though in this case, the math about this is well-defined: it's possible to increase a percentage either with addition or multiplication and both of those can make sense, just the words we would use to describe them are the same so it ends up ambiguous when you try going from math to English or vice versa.
But the fact that switching between communication language and a formal language/system like math isn't clear cut does throw a bit of a wrench in the "math doesn't lie". It's pretty well-established that statistics can be made to imply many different things, even contradictory things, depending on how they are measured and communicated.
This can apply to science more generally, too, because the scientific process depends on hypotheses expressed in communication language, experiments that rely on interpretation of the hypothesis, and conclusions that add another layer of interpretation on the whole thing. Science doesn't lie but humans can make mistakes when trying to do science. And it's also pretty well established that science media can often claim things that even the scientists it's trying to report on will disagree strongly with.
Though I will clarify that the "both" part is just on the translation. Formal systems like math are intended to be explicit about what they say. If you prove something in math, it's as true as anything else is in that system, assuming you didn't make a mistake in the proof.
Though even in a formal system, not everything that is true is provable, and it is still possible to express paradoxes (though I'd be surprised if it was possible to prove a paradox... And it would break the system if you could).
It's really pretty simple - if something increases by 80%, you add 80% of whatever it already is... one dollar becomes $1.80... one percent becomes 1.8 percent.
Most people don't understand it because they've seen it done wrong so often, the wrong way seems right.
I work in a place full of statisticians, and we've had to unfortunately have numerous conversations with some of them about the difference between "a decrease" and "a decrease in the rate." Apparently "it's increasing slower" isn't clear enough for some.
Maybe I'm understanding wrong but a decrease in the rate would be the derivative of a decrease. Aka the slope of the line. So if you are decreasing at -x. Rate of decrease is -1.
Unless I follow your wording incorrectly. Obviously it isn't always so nice of a function in real stats. Is that what they are missing?
I think it's more y=5x and then y=3x, so you're still increasing, but the rate of increase has decreased. Versus y=-x where the function is now decreasing.
Exactly. Unfortunately, they aren't used widely and consistently enough. Even in the press. So you frequently have to second guess what you're reading.
Fair enough, I'm inclined to agree. It's a relatively common error though, still leaving it ambiguous outside of circles where you expect people to express themselves with mathematical precision.
People got this wrong about inflation as well. In 2020 there was actual deflation, and in 2021 there was very minimal inflation, meaning prices were still largely lower or similar as 2019. Then we saw 9% inflation in 2022. Total inflation in 2024 vs the 2019 benchmark was around 15%. Or 3% average per year, which is barely over the baseline. People just hear 9% inflation, completely missing the fact that this was a YoY number relative to the Trump recession.
And then there was that bogus article that said Argentina had lowered it's inflation to 2% and you find out in the article that's monthly inflation and the yearly figure was like 190%.
If they managed to decrease from 190%/year to 2%/month (which is 27%/year) that's still an impressive result. Not as impressive to publish when you want to make a click bait.
I'm not sure how to put that to percentages thought, is it 86% and 143 percent points decrease?
Drag doesn't know exactly what the problem is, but the official inflation figures cannot be right. Housing is so much more expensive. Food is more expensive. And it's not 9% more expensive. Drag knows they say the math takes into account the price of rent, but they've gotta be lying somehow. It's impossible that the cost of living is rising so much faster than inflation. Those should be the same. If they're not the same, someone's math is wrong.
Why lying with maths is so easy, the average person, even in developed countries is practically innumerate (massive hyperbole, but the fact lying with numbers is easy, still stands)
Even more confusing when you hear that the odds of catching a disease have increased by a %. In many ways odds can be more intuitive, but we're so used to working with simple probability that it's a total nightmare to wrap your head around at first.
You know we say "a fraction of something" with a number(usually between 1 and zero) often denoted by letter epsilon. 4/5 equals 0.8 so there is nothing wrong in calling that a fraction too
The different ways in which numbers slide up, down, sideways, diagonally.
Is the example in the post part of the fifth type of arithmetic?
Addition +
Subtraction -
Multiplication x
Division /
Modulo %
The first time I learned about modulo as its' own branch of arithmetic was long out of school already, I had only hazily heard of it, on a PBS Nova documentary in the 1990s about Fermat's famous theorem and when it was proven after centuries of failed tries.
Yeah we just learned "by" was a standard term for multiplication. So increased by 80% was just 1.8 times whatever you started with. "Divide by" meaning multiply inversely
Language translating to artithmetic.
I'm sure it doesn't always line up, as we change language quite often.
I think it's ambiguous and the 90% actually makes more sense. If you increase something by 5m you are taking the original value and adding 5m to it. For multiplication you should probably avoid the word increase and say scaled by instead. 10% scaled by 180% is 18%.
Stupid people standing on soapboxes saying stupid shit.
Back in my day, people had to dedicate years of their life before they were given the opportunity to stand in front of hundreds of people and tell them things.
"If I return clothes to the store (store credit), but then buy new clothes (using that store credit), those new clothes are free. (No new money spent)"