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Comment by miffy900

11 hours ago

I really wish people would stop saying N times smaller than something when making a comparison; that makes no sense - it's 1/9th (11.11%) the size. You don't get a smaller quantity by multiplying by a number greater than 1.0. You could instead reverse the subjects being compared - "the original model is 9x bigger than this new smaller, efficient model" or some such. That makes sense.

I keep seeing this being used when people talk about efficiency or performance gains and it's just very unintuitive language.

I agree it makes little sense in a literal mathematical take but "it's 9x smaller" or is too much of linguistic advantage compared to "the original is 9x larger" or "it's 1/9th as large" to expect a change with. You don't have to invoke fractions, it keeps the thing in focus as the first subject, it matches the pattern of the inverse statement, and it's just plain short... so that's what people will adapt and interpret the meaning to be.

One other way to map both types of linguistic statement consistently to math is to interpret "9x" as "there is a 9 times difference between these two things" and then "smaller"/"larger" tells you which end of that separation the subject is (rather than specifying whether the multiplication builds up or down).

  • "it's 11% as large" avoids fractions but is much more clear (IMO) than "9x smaller" which my brain doesn't understand.

    • 11% is also a really saying a fraction, 11 per-cent or 11/100, but there's nothing wrong with that feeling more natural to some and it is at least a nice shorthand way for the written form. "A ninth the size" is a similar alternative. All are really fine, there's always someone who has trouble with a given representation compared to another.

If we were talking about speed instead of size, i think it would be perfectly reasonable to say 9x faster. I'm not sure I agree that 9x smaller is unintuitive. It makes sense to me.

  • "Nine times" literally means multiplied by nine, but here we're dividing by nine. It's not unintelligible (because the corrupted verbiage is so commonplace) but it is needlessly awkward. Like saying "resulted in a size reduction increase of 10 megabytes."

    • > "Nine times" literally means multiplied by nine

      Rather, "nine times larger" means multiplied by nine, and "nine times smaller" means divided by nine. This is basic and not particularly awkward, certainly not more so than e.g. positive/negative correlation, or many much more awkward and more common linguistic constructions, IMO.

      If you have to edit out words (i.e. context) to argue a phrase doesn't make sense... I am not sure what mental model you have for natural language, exactly, but it certainly isn't a very robust one.

  • "faster" relates to speed. Speed is related to time and speed of a thing is usually defined by time. 9x faster speed translates to time/9. There is an extra step of related conversion there.

    Conversely, 9x [filesize/natural number] is bigger. Every time. At least in the basic maths used by most people. There is no conversion into other units.

    Therefore "9x smaller" when talking about a natural number like filesize is a nonsense statement in logic terms. If you strive for unambiguous phrasing - which is a significant part of the programming experience - this logical nonsense might well perturb you.

    But english language is a flexible thing and if the phrase communicates your intent to your audience then that's fine by me.

    • I think more intuitively for speed - you are multiplying the things per period. If I’m making widgets 9x faster I have 9 x the previous number of units per period of time. To get the amount of time, you invert the ratio to period over units.

      Multiplying some scale by units per period makes sense and is both linguistically and mathematically sound.

It's simple

If 9 is "9 times greater" than 1 then 1 must be "9 times smaller" than 9

It'd help if you read "9 times" with the operator which is what's being flipped instead of with the number

Also, X is 9 times larger than Y and X is 9 times as large as Y are two different statements.

They probably rephrased it from some more technical form like "we compressed the model by a factor of 9" or "we've improved the packing efficiency of the model by 9x". Where these are measurements of the transformation the model is undergoing, not measurements of the resulting model.

This sounds like the same kind of error as writing "0.10 cents" because it's less than a dollar when the number is in dollars regardless of how big or small it is

But we're cutting drug prices 500, 800, 1700%! Numbers nobody thought were possible.

  • It was hilarious that this is the only time his, er, meta-imaginary-gains intensifier made the statement literally true.

Eh, when I read smaller with an integer multiplier, I mentally switch to the reciprocal. Easier than convincing the world not to use "9x smaller". Do you feel the same way about "9x faster"? What you're actually measuring is time, and "faster" is the reciprocal of time, similarly to "smaller" being the reciprocal of size.

  • yes, actually I do think the phrase 'N times faster' is sensible and logical

    if I say 'this Apple M5 chip is 3x faster' than this intel chip, it implies two things:

    - the run time of most operations that runs on it is now reduced (so one quantity is smaller)

    - but also: MORE WORK is being completed per unit of time compared to the intel chip (so this quantity is greater)

    So yes, a greater quantity is being measured in the apple chip compared to the intel when you say apple is N times faster. i guess this a quirk with the word 'faster' - it actually measures two things, time and work performed per unit of time. the word smaller just measures size.

    like, if I give a customer a cup of coffee one day, then give them a SMALLER cup of coffee the next day, for the same price, but declare "It's now 2X more space efficient!" i.e. it's now half the size, I'm certain the customer is gonna be pissed.

    • Ah, but in this case the customer is buying the coffee for the caffeine content. And you've doubled the caffeine content per volume! Twice as efficient a delivery mechanism, similar to this model!