A place for majestic STEMLORD peacocking, as well as memes about the realities of working in a lab.
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This is a science community. We use the Dawkins definition of meme.
Wrong: I had a 1% chance, and I doubled my chances. Now my chances are 101%.
Right: I had a 1% chance, and I doubled my chances. Now my chances are 2%.
Wrighongt: I had a 1% chance, and I doubled my chances. Now my chances are 3%, because I'm a lucky person.
Funny thing is this is a language issue, not a math issue.
I know all this. I play DPS!
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.
Can't believe nobody has linked the relevant xkcd yet
Which of course is why people referred to points when discussing stocks/markets. Got to love an unambiguous term.
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I've always wondered how to disambiguate multiplication and addition of percentages. I guess that's what percentage points are for?
The annoying part is that there is no well-known notation for showing percentage points, so people use % for both percentages and percentage points.
I like how some games use "increases by +10%" as percentage points and "increases by 10%" as percentage.
Or how oath of exile does it, with "(base + base * increases by y%) * z% more"
So with a base of 5%, chance increased by 20%, and chance increased by 30%, with a 40% more chance, you'd get:
(5% + 5% x (20% + 30%)) x (1+40%) = 7.5% x 1.4 = 10.5%
In deep rock galactic survival, the color of the number is different for percentage and percentage points
We really should just have a different symbol tho. Maybe we do, I'm not a math wiz, but we certainly don't have a broadly used one.
10% of your people vote for a party.
The votes increase by 10% => now 11%
The votes increase by 200% => now 30%
The votes increased by 50 percent points => now 60%
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.
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'm quite willing to bet that 70% of the population has no clue that percentages, fractions, and decimals are the same thing.
Then odds show up to the party and upend everything we thought we understood.
That's about 60% more than expected
You mean 38 percent points higher ?
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.
Maybe I'm wrong but by writing "increase by 80%" there is ambiguity you don't get if you instead spelled out:
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.
Im a high school maths teacher and that's what we're supposed to teach, % means percent, not percentage points. Maths always tries to have agreed-upon unambiguous definitions of things, precisely to avoid confusion.
Maths always tries to have agreed-upon unambiguous definitions of things, precisely to avoid confusion.
Laughs in ambiguous notation
I thought of an example or two and corrected my comment to 'tries to' as I was typing haha
Or "by 80 percentage points"
"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.
I know. By x % and by x percentage points is the most commonly confused pair, not by x % and to x %.
well it's ambiguous. Its also a sloppy way of expressing an increase by 80 percentage points.
Dark Souls cleared this up for me real quick.
Having two possible outcomes does not mean it's a 50:50 chance.
"So if I aim the arrow at the 1cm square from 100m away and shoot, I either hit it or I don't. So basically I have a 50% chance of hitting it."
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.
I play video games; I need to know if the percentage is additive or multiplicative.
"+100%" looks pretty good until you see what "×25%" actually gives you.