That’s about the size of it


News reporters seem to have some difficulty reporting the size of things. In order to make things more accessible to their readers, they try to compare it to the size of an everyday object, but to me it seems they try a bit too hard. For example, this story about the recent rescue of the crew of a sunken submarine noted,

[T]he layers of stretched nylon appeared to be as thick as a 1 1/2-inch cable.

"As thick as a 1 1/2-inch cable". As opposed to "as thick as a 1 1/2-inch stick" or "as thick as a 1 1/2-inch thing that is about 1 1/2 inches thick". May I humbly suggest, "The layers of stretched nylon appeared to be 1 1/2 inches thick", or if you want to emphasize the shape, "The layers of stretched nylon appeared to form a cable 1 1/2 inches thick".

On a similar note, back in 1997, All Things Considered talked to Major Mike Morgan, deputy director of the Space Control Center, the people who track space objects 10cm or larger. Major Morgan translated this from metric to American units as follows:

That's about the size of a three-inch bolt.

Actually, 10cm is 3.9 inches; if he wanted to remain fixated on bolts, he should've said "That's about the size of a four-inch bolt." (And don't forget that a kilogram weighs about the same as two pounds of pebbles.)

On the other hand, you can sometimes miss the mark by providing too little information about an everyday object. Describing an inflatable satellite being deployed by the Space Shuttle back in 1996, the NPR space reporter said that it "grew to the size of a giant silver pie pan".

How big is a giant silver pie pan? I figure about 40cm (18in), that's a pretty big pie. (In reality, NASA says it was about 50 feet [15m] in diameter.)

Comments (37)
  1. Smelly says:

    I’ve never understood the compulsion to explain the size of really big things in terms of football fields.

  2. dailey says:

    Slate had a funny article a while back noting people’s insistance on comparing everything to the size of Rhode Island

    http://slate.msn.com/id/2090806/

  3. Rikard says:

    Smelly: Me neither. I would have understood a number of km2 better, but often the only say "an area the size of x football fields".

  4. Hehe, this reminds me of a summer job I had in a small ice-cream and candy shop. One day this kid of ~10 yrs comes and asks me: "How much are the $1-bag of candies?"

  5. Richard says:

    Isn’t a three-inch bolt three inches of thread and then the head, so a three-inch bolt is actually about 3.7 inches?

  6. I stopped reading newspapers a long while ago, because the news stories showed such poor writing skill that I couldn’t focus on the content anymore.

    I used to work as a journalist, long ago. Consequently, I get kind of picky about the language used in journalistic writing. Much of what I see today shows remarkably poor writing skills from a group of people who really should know better.

    I know I can pick up a newspaper today and zero in on a news story with any of a variety of grammatical errors, awkward wordings, usage of nonstandard stylistic writing, and other such gaffs, the likes of which you’d expect an editor to resolve prior to publication.

    This sort of observation exemplifies that kind of nonsense I’ve seen in popular journalism for the last 10 years now. Truly, I wonder if we really care anymore.

  7. All those crappy descriptions that are so misleading remind me to much of most of the MAN pages I have read.

    In the end, you still have no idea what is being talked about.

    Shameless plug alert: I moved my blog for those of you who may be reading on my end.

    jamessummerlin.blogspot.com

    James

  8. Daveh says:

    "Isn’t a three-inch bolt three inches of thread and then the head, so a three-inch bolt is actually about 3.7 inches?"

    It depends on the type of the bolt head. Bolt/screw lengths are generally given from the point of the largest diameter on the head, so a 3" bolt may indeed be actually longer than that.

    See http://home.jtan.com/~joe/KIAT/kiat_2.htm

  9. JT says:

    Slightly OT, but a few years ago a not-too-swift salesman i work with visited a couple of food factories and reported to me that he saw an extruder running at 4 millimeters/minute (not 4 m/min) and a cakes that were 50×50 meters (not 50×50 cm). He hated it when I questioned his observations.

  10. Steve Hiner says:

    All of you would enjoy the books by John Allen Paulos (I think that’s the right spelling). He wrote:

    Innumeracy: The Consequences of Non-mathematical Thinking

    and

    A Mathematician Reads the Newspaper

    The second one is especially relevant but both cover similar topics (I think Innumeracy is a better read).

  11. Maurits says:

    Writing is only 30% about facts, and 70% about connotations. Analogies are a free way to pull in your favorite connotation.

  12. vishnu vyas says:

    LOL.. interesting read, this is the only reason I keep returning to this blog again and again!

  13. foxyshadis says:

    "as thick as a 1 1/2 inch cable" shows more a distinct lack of imagination (can he not think of anything that thick without resorting to including the measure, such as a small pipe or a young tree trunk?) than overreaching for the masses’ sake.

  14. Scott says:

    This brings to mind how they will sometimes compare things to the "weight of a 747". If I wanted to pick a thing for comparison’s sake, I wouldn’t pick something that’s intentionally built as light as possible.

  15. Gridman says:

    I’ve mostly noticed that things of great force or things that release a great deal of energy, (hurricanes, earthquakes etc) are referenced to Hiroshima atomic bombs. They omit the small detail of the RATE of the energy release.

    I have not tried to calculate it, but I wouldn’t be surprised that the energy released by the falling leaves of autumn would equate to X number of Hiroshima atomic bombs.

  16. James Schend says:

    The thing that bothers me about "the size of a football field"… are they including the end zones? The end zones make a huge difference when you’re talking about size. (I get the general impression that "size of a football field" means 100 yards, or with no end zones. But it’s still stupid… if you’re going to use a moronic made-up unit, at least make sure it’s a precise one.)

  17. Tim of Angle says:

    "As thick as a 1 1/2-inch cable" does not, in fact, mean 1 1/2 inches thick – cables are rated by circumference, not by diameter, so a 1 1/2-inch cable would be slightly less than 1/2 inch thick. (Why someone would think that the comparison would mean anything to anybody other than an old sailor is, of course, another question.)

  18. Jerry Pisk says:

    End zones are not the only sticky issues – are they talking about the width, length (with or without end zones) or maybe the area of a football field?

  19. Buxley says:

    A related pet peeve of mine is conjuring more significant digits of accuracy than appropriate while doing some sort of conversion. For example, a newspaper story talking about a 747 flying at "a cruising altitude of 32000 feet (9754 meters)." Somehow two significant digits have been stretch to four…

  20. Tom Seddon says:

    "football field" is always dubious anyway, end zones or no, as nobody ever specifies which game they are talking about :)

  21. Arlie Davis says:

    Football fields and human hairs are the SI units of middle America.

    It’s especially ridiculous when writers say that "blah blah is only 4 nanometers wide — that’s less than 1/12045th of a human hair!". Human minds don’t work that way. Once you get to "tiny", everything is "tiny". There is no meaningful distinction between "1/12045th of a hair" and "1/54021th of a human hair". Unless you’re measuring small things with precision instruments, in which case you use units like mm, um, nm, etc.

    Writers should just say 50um and be done with it. I expect high school graduates to understand at least that much.

    Other annoyances:

    * "As small as the period at the end of this sentence." What typeface, what point size?

    * "A thimble of X in a swimming pool." Meaningless. Just say N parts-per-million or parts-per-billion. It still conveys the magnitude of the ratio (everyone knows how many bucks are in a million bucks, right?), and it gives *accurate* information to people who deal in ppm/ppb. It also uses fewer words.

    * "The size of a baby’s fist." Do we have an SI reference baby? Can’t we just say "two inches in diameter"?

  22. Jonas Grumby says:

    Some of those remind me of that email that went around about the worst HS creative writing analogies… things like "He was as tall as a 6 foot 4 inch tree", or "the brick wall was the color of a brick red crayola crayon".

  23. denis says:

    Buxley:

    "’a cruising altitude of 32000 feet (9754 meters).’ Somehow two significant digits have been stretch to four…"

    True as far as it concerns non-science writing. However, in science work, if you wish to retain the same level of accuracy, you must convert 32000 feet to the more explicit form (32000 +- 500), and this into meters as (9754 +- 152.4). Any omission loses accuracy, and at least as far as conversions of a single figure are concerned, accuracy can only be lost, not gained, so that is something to avoid…

  24. Pax says:

    Buxley:

    "’a cruising altitude of 32000 feet (9754 meters).’ Somehow two significant digits have been stretch to four…".

    Reminds me of a joke about the museum curator giving a tour and telling the assembled masses that the dinosaur bones in this display were 65,000,017 years old.

    When questioned about how he could be so certain, he replied "Well, I started here 17 years ago and they told me then that these bones were 65,000,000 years old, so …".

    Pax.

  25. Norman Diamond says:

    (And don’t forget that a kilogram weighs

    > about the same as two pounds of pebbles.)

    Yup, zero equals zero. Remember, they’re in orbit. No weight for multiple objects.

    But one kg still masses one kg, even if it’s on the moon where it weighs about 16% of what it would weigh on earth.

    Tuesday, August 09, 2005 11:14 AM by Andreas Magnusson

    > One day this kid of ~10 yrs comes and asks

    > me: "How much are the $1-bag of candies?"

    The kid might have previously lived in or visited a country where taxes are added onto the posted price. Japan was that way for a few years. Prior to that, when most Japanese had no experience with that kind of system, when they visited certain other countries they would be confused when a $1.00 item came to $1.07 or whatever.

    Tuesday, August 09, 2005 11:49 AM by Arlie Davis

    > Football fields and human hairs are the SI

    > units of middle America.

    Used in most of the world except for middle America and sometimes a few other random countries? Or perhaps you mean that football fields and human hairs are the NON-SI units of middle America?

  26. pUnk says:

    "I stopped reading newspapers a long while ago, because the news stories showed such poor writing skill that I couldn’t focus on the content anymore." — Trey

    Me too. Now I read blogs.

  27. TC says:

    Some folks said:

    > > "’a cruising altitude of 32000 feet

    > > (9754 meters).’ Somehow two significant

    > > digits have been stretch to four…"

    > True as far as it concerns non-science

    > writing. However, in science work, if you

    > wish to retain the same level of accuracy,

    > you must convert 32000 feet to the more

    > explicit form (32000 +- 500), and this into

    > meters as (9754 +- 152.4) …

    Huh? Say I define a new unit called the Duh. 1 Duh = 1.23456789 feet precisely. Are you saying that "to retain the same level of accuracy", a measurement of "1000 Duh’s" should be translated to "1234.56789 feet" (+- whatever)? That seems, to me, to be creating significant figures where none existed before.

    TC

  28. Nick Lamb says:

    The aircraft altitude example has two red herrings

    1. Unlike a scientific measurement it does not include a good indication of precision or accuracy. We may reasonably assume that it’s not precise to +/- 1mm since the unit used is too large, but can we conclude that they mean +/- 1000ft ? Why not +/- 100ft or even 0.5 ft ?

    2. Actually the precision (in meters) is about right. The auto-pilot on a passenger jet is easily good enough to maintain stable cruise with a variation of perhaps a couple of metres. The pilot dials in the altitude specified by control, which will always be a round number, so the main source of error is the accuracy of the altimeter, and those are getting very good these days.

  29. Norman:

    > The kid might have previously lived in or visited a country where taxes are added onto the posted price.

    Nah, I doubt it, it was more the case that we had two kinds of pre-packed candy bags. One was about $0.5 and the other about $1 (this was in Sweden so I’ve made a very rough currency conversion). Thus we nick-named the candy bags "$0.5-bag" and "$1-bag".

  30. Robert Konigsberg says:

    Actually, 10cm is 3.9 inches; if he wanted to remain fixated on bolts, he should’ve said "That’s about the size of a four-inch bolt."

    He’s an astronomer, being within an order of magnitude is impressive.

  31. anon says:

    My favourite unhelpful conversion was in a recent article that noted that "£1 in every £5 spent in the UK was spent…", which was converted along the lines of: "$1.71 in every $8.55…"

  32. Dewi Morgan says:

    New Scientist’s Feedback section is a great source of these. Some choice quotes froma quick archive search…

    13 Dec: from an article entitled "Gritty facts" in a recent Norfolk County Council newsletter:

    "Norfolk County Council will stockpile 13,000 tonnes of salt for the coming winter, that’s about the same weight as 1625 killer whales.

    "Each gritter will be sent out carrying on average 6.5 tonnes of salt, that’s the equivalent of 12 polar bears.

    "It sounds a lot, but not when you consider the 56 frontline gritters will be covering a distance of 1839 miles of priority routes. That’s almost the same distance as to Moscow and halfway back!"

    20 Dec: The BBC South Ceefax page recently ran a report about Britain’s biggest Christmas tree, […] assuring us that the tree[…] is "as bright as 27 electric fires"

    9 July: FORBES Magazine [contained] an article stating that 1 in 8 pounds sterling spent in British shops goes to the supermarket chain Tesco. Then, […] it helpfully informs us that this is equivalent to 1.89 in every 15.15 US dollars or 1.43 in every 11.48 euros.

    30 July (and the best of the bunch!): Gregory Skinner stumbled on the "Ciao! shopping intelligence" review of the Canon BJC 85 printer. This tells us that: "The printer is tiny – about a 12-inch ruler long by half a 12-inch ruler wide"

    …there are many more, and thousands more scientific ausements, but I guess you’d have to subscribe to read them all.

  33. Colin Wilson says:

    Here in the UK, sizes of landmasses are for some reason always equated to the size of Wales.

    I spotted one just today in The Register –

    http://www.theregister.co.uk/2005/08/11/melting_siberia_threat

    ‘The Size of Wales’ even has it’s own Wikipedia entry –

    http://en.wikipedia.org/wiki/The_size_of_Wales

  34. You guys are too busy being ‘smart’ to notice that the holes that you are poking may not be holes at all.

    If one is talking about detection of objects, saying that something is the size of a "3-inch bolt" indicates that only one measure is provided. The remaining dimensions are to be experientially determined by the listener. Stating this size with an example bolt (they keep several at the Space Control Center) indicates that they track objects with less volume/mass than, say, 3-inch metal cubes.

    A cruising altitude of 32,000 feet is *just* that. This would indicate a Westbound flight, as Eastbound flights cruise at intervals of odd thousands of feet. This is not a matter of significant digits. It’s done to keep planes flying in opposite directions at least 1000 feet from one another. Of course, all of these altitudes are as read on altimeters set to 29.92 inches of mercury in Class A airspace (from 18,000 feet to 60,000 feet). This keeps all aircraft with properly calibrated altimeters on the same page.

    And, no, one’s weight in orbit is not appreciably less than one’s weight on the earth’s surface. Weight describes the attraction between two bodies, and the constant ‘freefall’ of a body in orbit gives the appearance of weightlessness. Here’s a link to a lesson that, from the looks of it, is intended for children:

    http://www.glenbrook.k12.il.us/gbssci/phys/Class/circles/u6l4d.html

    There is a difference between being pedantic and being inaccurate. Make sure that you’re on the right side of this line before you deride the foibles of others.

  35. CornedBee says:

    Some of these comparisons, e.g. the 12-inch ruler, may seem stupid, but actually help comprehension. Now, I use centimeters, not inches, but let’s say they talk about "as long as a 30-centimeter ruler". Now, if they said "30 centimeters long" I’d probably within half a second could imagine how long, approximately, that is. But mentioning the very common ruler length of 30 centimeters as a reference gives me an immediate understanding, without any delay.

    The human mind is just not all that well suited to deal with abstract numbers. Analogies, even when they sound stupid, are more intuitive.

    That’s not an excuse for 1509 killer whales. First, I have no idea what a killer whale actually wheighs, so the whole thing does not help my understanding in the least. Second, the number of whales given is already so large that we get back to abstract numbers, giving no advantage over the metrics.

    Now, if they said that it’s about the weight of a frigate or something …

  36. Howard Cheng says:

    Reminds me of an old SNL Weekend Update bit where Dennis Miller explains the $1 trillion deficit (don’t remember the exact figure) as such: Imagine you had 100-billion-dollar bills. It would take ten of those to match the deficit!

  37. David Walker says:

    "Analogies are a free way to pull in your favorite connotation."

    My Dad hates analogies. He says "Tell me the thing itself, don’t tell me something else that it’s similar to."

    I read the following somewhere: "Analogies are like feathers on a snake".

    Yes, it’s recursive. Analogies are unhelpful, unnecessary, and so on. For some people, at least, and especially when they are used poorly. I suppose analogies can occasionally be helpful, when they are not stupid.

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