2684: Road Space Comparison

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Road Space Comparison
I wonder how hard it would be to ride an electric scooter in a hamster ball.
Title text: I wonder how hard it would be to ride an electric scooter in a hamster ball.


The comic is a parody of a common comparison done in arguments for public transport and walkable cities - the amount of usable space taken up by cars and car-centric infrastructure that could be eliminated for other useful public amenities. The first of these may be from 1965[1].

The first 4 images are common, real-life comparisons involving people walking, people on bicycles, public transport, and cars, which distinctly show how cars take up significantly more space for the same number of people than the other methods of transport. However, from this point the comic becomes more and more absurd in its comparisons.

  • The 5th image shows 50 people on what is reported to be a tandem bicycle, although it seems more likely to actually be a string of trailer bikes, due to it not being rigid and the separation from one person to the next is larger than is typical for tandem bicycles. This would obviously be impractical in a city due to the tandem's sheer length and it would not be able to work with fewer than 50 people due to its sheer mass. The longest compound cycle holds 52 people, while an actual tandem bicycle exists that has at least 35 seats.
  • The 6th one involves 20 people driving 40 cars, with each person driving 2 cars at a time by straddling them in the middle. Besides being unwieldy and impractical, it would also be extremely dangerous as the cars could go out of control at any time. Perhaps the cars would be a paired mix of left-hand-drive and right-hand-drive models, although with enough push-rods/levers (to also reach the traditional foot controls, and also gear sticks unless fully automatic) this might not be as important. However, even if the cars were perfectly safe to drive, it would be unsafe to drive them on most roads; roads with only one lane per direction are common, everywhere from city streets to exit ramps, and attempts to drive a pair of cars down such a road side by side are unlikely to end well. (Of course, worse than any of these petty safety concerns is the fact that each person takes up twice as much road space, making most infrastructure a bit less efficient. Of all the examples, this is the most wasteful of space, with the entire road being taken up by only 20 people.)
  • The 7th one has 30 cars riding on 6 buses by stacking them on top of each other. Assuming the same people-per-car/bus from the earlier examples, this arrangement would have about 345 people riding on the same road! (Unless, of course, the buses are carrying 30 cars instead of their normal passengers.) In addition, people getting out of the cars when they reach their destination would be a problem for most cars in this arrangement due to them being stacked under other cars or surrounded by them. And as in the previous example, it would be impossible to safely drive anywhere without two clear lanes...and the body count would be considerably higher.
  • The 8th panel has 50 people in hamster balls. Randall has shown his interest in human sized hamster ball transportation before, and indeed, for some people, this might be an enjoyable way to traverse a road, provided no other hamster balls try to drive into you and knock you off the road, and other traffic that could pose a greater hazard has been eliminated. The image shows 39 hamster balls, implying that roughly one in four has a passenger; under these constraints, they appear to be slightly more efficient than cars. Another explanation for 39 balls is that there are more hamster balls than are able to be shown on the road diagram -- this is supported by the fact that only one "person dot" is shown in each of the hamster balls, however since the diagram is supposed to show visibly what it looks like to have that many vehicles/people on the road at the same time, missing hamster balls negates the purpose of such a diagram.
  • The 9th panel has 40 tiny cars pulling a big one. Such feats of strengths are a common sight while setting world records, so maybe this is a world record attempt by the cars in question. It is unknown how many people fit in the big car; judging by its size, it likely fits more than a single bus and less than three. It is also unclear whether the tiny cars can fit a human driver, or if they would need to be driven remotely.
  • The 10th panel is a 50 person variation on the classic wolf, goat and cabbage problem (which has been referenced before in 589: Designated Drivers, 1134: Logic Boat, and 2348: Boat Puzzle) except this one involves 30 goats, 20 cabbages and 10 wolves trying to cross a section of road that is underwater, using a single boat. The fact that there is a conveniently placed dock at the edge of the water suggests that this is a ford with provision for those crossing by foot, or at least that the road gets flooded often enough to warrant a permanent dock to be installed. It is not known how many people (or cabbages for that matter) the boat fits, but since humans significantly outnumber the goats, cabbages and wolves, it seems like a much simpler problem, though not necessarily without difficulty.

The initial bicycles and singular bus are actually (mostly) using the left-hand lane of the three shown, for whatever reason. This would not be unusual on British highways or other countries using their system, whether the lanes seen are just one of the directional carriageways of a multi-lane split highway or the centre-lane is a gantry-signed 'tidal lane' of a fully two-way street. Yet people who have to walk on a road (due to no footway) are advised to walk facing oncoming traffic (the right-hand side, in the same jurisdiction) and not bunched up. It would be interesting to know why Randall, much more familiar with US road conventions, would have offset these various road-users the way he did (rather than hogging the central lane, or across the entire highway width as he did with the other diagrams in the series).

The title text proposes a problem related to another alternative form of transport — the electric scooter. Randall wonders how well an electric scooter would function when run inside the hamster ball. While this could function like a spherical monowheel, it might also be very dangerous.


[Overhead views of ten segments of highway in two rows with a caption above. Each road segment has a caption and a different scenario.]
Road Space Comparison
[50 people in the bottom left of the highway, all fitting into a single lane and taking up about a fourth of the length of the road.]
50 people walking
[50 bike riders in the bottom left of the highway, extending about halfway up the road and spilling over slightly into the second-to-leftmost lane]
50 people riding bikes
[A single bus, fitting into roughly the same space as the 50 people from the first scenario]
50 people riding a bus
[33 cars, taking up the entire length of all three lanes]
50 people in 33 cars
[One long string of connected bike riders, curving slightly and extending down the entire length of the middle lane]
50 people on one tandem bicycle
[40 cars in pairs, each pair with a single person straddling the windows between them. They take up the entire highway segment and each pair extends partway from the outer lanes into the middle]
20 people driving 40 cars
[Six buses on the lines between lanes taking up the majority of the highway, 30 cars arranged in stacks across the top]
30 cars riding on 6 buses
[39 evenly-spaced hamster balls with a person inside each, taking up the majority of the highway except a space at the top]
50 people in human-sized hamster balls
[An oversized car taking up all three lanes at the bottom of the highway, with a pair of ropes and a beam attached to the front bumper. The beam is attached to 40 miniature cars in front arranged into four lines]
One giant car pulled by 40 tiny ones
[The road is bisected by a large river taking up about half of its original area, with a dock and rowboat attached to the lower shore. 50 people, 30 goats, 20 cabbages, and 10 wolves are in groups on the same side]
50 people with 30 goats, 20 cabbages, and 10 wolves.

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Hold on, I'm trying to concoct an interesting 30 goats/20 cabbages/10 wolves problem... GreatWyrmGold (talk) 20:53, 12 October 2022 (UTC) S3C0ND P0ST 21:12, 12 October 2022 (UTC)

You have no idea how many car-centric infrastructure arguments happen in my discord servers, this is a fantastic comic to post for that188.114.102.55 21:23, 12 October 2022 (UTC)

What if the last panel also references other river crossing puzzles like the "Missionaries and cannibals problem" or the Flash "Japanese River Crossing" puzzle so you have extra rules for each member of each species? 22:11, 12 October 2022 (UTC) Alex

My name is GreyFox, and I added the transcript for this page. 22:13, 12 October 2022 (UTC)

Aww, they removed my table! I liked that table. -- 21:39, 17 October 2022 (UTC)

So the takeway is... we can put humans in hamster balls by the handful all season and feel no worse about it than about cars driving down the road? This is awesome! 22:20, 12 October 2022 (UTC)

No, unfortunately the comic is missleading! Even though it is labelled as 50 hamsterballs the image only shows 39! Lupo (talk)
The comic never said it was one person per hamsterball. There's plenty of space in those for the hamster equivalent of a sidecar. GreatWyrmGold (talk) 05:30, 13 October 2022 (UTC)
But the image shows only one shioulette per hamsterball. I assume this picture is intentionally misleading and Randall was payd by the hamsterball-industry in order to manipulate society towards being pro hamster-ball Lupo (talk)
Eleven of the silhouettes could be of people wearing an occupied baby-carrier. The varieties of the silhouettes could allow it without requiring finer detail. These Are Not The Comments You Are Looking For (talk) 02:06, 17 October 2022 (UTC)
Regarding the hamster wheels: I think the description is missing a reference to sphere packing. It’s the first thing I thought of when I saw panel 8: how many circles/spheres can you fit/pack into a given space is a famous mathematical problem that I believe Randall has played with before., 13 October 2022 (UTC)

Saw this one recently, can't be a coincidence NL Fietsersbond Ruimtegebruik 22:25, 12 October 2022 (UTC)

No, it can not. -- 16:13, 13 October 2022 (UTC)

I'm a bit unsure about the linked "52 person tandem" (also, the way it is currently made a bottom-of-page reference link, which we avoid on this site). It took me a while (behind all the popups the referenced link gave me, typically) to realise the only picture of it was the miniscule thumbnail planted at the start. Which explained the anomolous wheel-count, if I understand the low-res image correctly. I would dispute Ripleys'/Guiness's acceptance of that thing as a 'tandem'. It is clearly a multi-stage Rann Trailer-style construction (possibly with individual tandem-'trailers' in there to get the wheel count down to no more than the rider-count). Also, how on earth would a linked line of trailers actually start bursting tyres? The load of riders plus frames would spread out about as evenly as for any given single occupant bike (certainly less than the forces on the wheels of a proper tandem/trandem, or even a tandem-trike!), so I'm not sure how they even buckled a wheel. So I'd like to know what the longest two-/three-wheel tandem is (and certainly how anything like Randall's slightly snaking frame does not buckle), if anybody has their finger on that rather more relevent information, rather than that faux-tandem. 03:03, 13 October 2022 (UTC)

Is it just me, or is the last block also a subtle dig at Putin's blown-up Kerch bridge? 12:22, 13 October 2022 (UTC)

then it would be 50 people with 30 sleeping bags, 20 guns and 10 medikits :) Lupo (talk)

Intrinsic problems to the multi-human/goat/cabbage/wolf riddle:

- How many generic objects can you take at once? (If you can take 110+, there is no riddle here)

- How many goats can one person transport at once? (Can you put 30 goats on a boat without pandemonium?)

- How many people are required to corral the goats? (Will the goats all run away when they get to the other side?)

- Are the humans able to catch the goats? And, if the humans *can* catch the goats, does that mean the wolves can, too?

- Is there a way to restrain the wolves?

- Can a wolf be lonely?--Cwallenpoole (talk) 13:23, 13 October 2022 (UTC)

"Can you put 30 goats on a boat without pandemonium?" - nicely done. :o) 13:51, 13 October 2022 (UTC)
If one person only is needed to "corral" 30 Goats/Wolves/Cabbages, then the problem is moot - the first boat ride just leaves a human on the other side of the water to watch over whatever is brought 14:20, 13 October 2022 (UTC)

I suppose instead of being critical numbers it has to be done with critical ratios. Gives you a little more wiggle room in the ordering of the trips and optimization but would read basically as the solution to the original but 25 times in a row.

*raises eyebrows at the suggestion that a 50-person tandem is only impractical in a city...* 13:52, 13 October 2022 (UTC)

The multiseater 'bike' drawing is off, for me. A tandem (including trandem, quad, quint, etc) tends to root the stoker's(/subsequent stokers') handlebars directly under the seat of the rider in front of them (steersman/intermediate stokers) in any decent scratch-built frame, not well behind the seated body (and presmably a head/hat of each person, seated upright). It's closer in longitudinal scale to what you get of an overhead view of a compound bike with handlebars on or just behind the towing-point (though now it looks a little too close, practically, as there might not be room between the bottom-bracket/down-tube/head-tube to clear the rear wheel of the bike-rear in front of them... if not Moulton-sized units, which causes other building problems). Which also perhaps accounts for the slightly snaking plan view, being articulated. If well constructed with the right attachment geometries, this could actually travel city streets quite well by ensuring the wheel track of each compound unit follows the path of the weaving wheel(s) ahead of them. Although it'd need practiced riders to prevent lateral oscilations causing rolling forces to drag the whole thing sideways down to hit the ground. But I'll forgive Randall, as he clearly doesn't have enough practical experience with bike/tandem construction. Anyway, as the original '52 seat tandem bicycle' link was not a tandem (nor a bicycle) I looked up what I think is the correct most-seated tandem (tried checking Guiness Book Of Records website, just in case, but its cookie-authorisation popovers made it impossible to read) and added that as well as caveating the existing presumption of tandemness for the drawing and the already suggested machine. 18:54, 13 October 2022 (UTC)

There used to be a lot of videos on YouTube with rigid human-sized hamster balls, but the only ones I can find are the flexible inflatables now, and all the stunts seem to be with concentric inner compartment inside a shock-absorbed outer core. Wasn't there some horrible injury in the news some years back? 08:30, 14 October 2022 (UTC)

The “one giant pulled by many smalls” thing has been done by Märklin (manufacturer of H0-scale locomotives). 200 H0-scale locomotives pulled one real passenger wagon. Of course, similar stuff has been done by other groups. -- 13:51, 14 October 2022 (UTC)

Note that, as the author of this removed statement, I can absolutely tell that other editor that it was not written as an anti-bicycle statement, but as a cyclist. Not worth reinstating, but the image given clearly goes against both my own and the generally accepted official rules in my location. It does annoy motorists (and pedestrians; and me, in whatever capacity I am currently journeying) when ill-informed/uncaring/provocative people on bikes flout those rules, and then makes it worse for those who obey the rules (ride abreast, at any given time, because it would never be safer for a motorist to pass a vastly longer single-file group; or simply to ride on the road, as is both our right and responsibility). Not knowing how the rules and regs work outside the UK (but assuming that the practical conventions are similar, where not totally over-regulated out of existence) I had wanted to just say that a 'peleton group' like that is not good practice on the open-road.
And, obviously, there are exceptional circumstances (if not rules being bent) if we see human-hamsterballs, cars stacked atop other vehicles, stradle-driving and insisting on taking wolves(/etc) through a flooded section of road, which may or may not be 'open' in any real sense, especially to other forms of traffic... But I'm a lot more familiar with the cycling issue, so I added that pro-cycling bit of advice. Not that it will improve matters, or significantly add to understanding, but it made me feel a tiny bit better at the time, and so thanks for reading. 10:07, 17 October 2022 (UTC)

Bias may not have been intended, but that doesn't mean that (socialised and internalised) bias wasn't present. It's a common misconception, but there are no rules against riding abreast or in groups in the UK, and it's often recognised that it can be safer for cyclists to do so. Where there are such rules, they are anti-cycling rules, designed to move cyclists over out of the way of the supposedly more important motor traffic. Motorists aren't annoyed by the cyclists, per se - they're annoyed because their perceived superiority as road users is challenged by having to wait behind. 13:17, 19 October 2022 (UTC)
This does not contradict the statement that riding excessively abreast (i.e. across multiple lanes) does no favours to the cycling community (my community). As an act of protest, you may be able to do many things that aren't technically illegal but for which annoyance of others is going to be a self-defeating activity if you want those in the wrong (misinformed motorists, especially) to learn and understand and appreciate.
The recent resurgent demand for "bicycle licence plates", unworkable as it is, arose not just from people doing outright illegal things (like using pavements, junping lights, reckless riding in general) but also being inconsiderate..
I'm involved in cycle-sport, racing on the road, and the right to do this has been historically retained (and actually engrained in law) against a background of anti-cycling opinion, and I would like this to continue. It is not just the ignorant outsider, who maybe I could enlighten and get on side (as if there's any hope of that), but also those participants (or non-participants who nevertheless are seen as the same in the eyes of the outsider) who bring the sport into disrepute by not obeying the Highway Code, etc.
And group-riding in a peleton fashion (without being in a peleton, anyway, the management of which I leave to those responsible for mass-start races who are additionally already required to get police permission/road-closures arranged) doesn't make a safer environment and doesn't help the (rightful) acceptance of cycling by those who observe such apparent chaos. It's bad enough with the perfectly legal two-abreast group riding which, as you say and which I obviously know perfectly well, is also often the safest option.
The perceived superiority of motorists vs others (or indeed others vs everyone else, as a pedestrian I've been verbally abused/threatened by pavement-riders!) is a problem which doesn't get fixed by thoughtlessness, hot-headedness or basic impetuosity. 19:35, 19 October 2022 (UTC)
The bias comes in, though, when you only comment on the behaviour and supposed inconsiderateness of the cyclists in the comic, and not on that of the other road users depicted. The 'peleton' of cars in panel 4 is actually far more likely to be encountered in urban areas, can be equally a catalyst for frustration and annoyance for other road users who are obstructed by it (in this case, often cyclists), and likely involves a lot of thoughtlessness and inconsiderateness in that drivers have chosen to make unnecessary journeys by car. But no-one comments on that (suggesting that they should break up into smaller groups to make it easier for other road users to negotiate around them, for example), because of the ingrained societal bias that cars on the road are 'normal', whereas bicycles are an aberration, and should get out of the way of 'proper traffic'. 08:41, 20 October 2022 (UTC)
Maybe if they could act like proper traffic, they wouldn't be seen as a meanace or problem as opposed to 'normal' traffic. I can't even count with all 20 fingers in my body the amount of times a bike rider almost crashed into me just this past year alone because they've got it into their heads they get to use roads, but don't have to follow traffic lights like everyone else and are exempt from keeping an eye our for pedestrians or other traffic. -- 15:08, 25 October 2022 (UTC)
Driving just yesterday: other cars exceeding the speed limit; the same cars (or those from the other direction) overtaking and having to cut back in because of opposing traffic/myself; has that light changed to red..? - never mind, continue through; well, you're using your indicators on the traffic island but you're signalling your exit way too early/late and might as well not have bothered; never mind those lane markings, you can cut across/straddle however you like; car parks... the second frame of this happened (but not the rest, unfortunately). Cyclists on the road, less problem than the horses ridden on the road (not an issue, I held behind) or encountering vehicles on narrow lanes where I needed to use passing places/the verge to allow us to pass each other).
Bike riders can be bad road users, but they're probably the same people who are bad road users when driving cars, or the uneducated young (there used to be some regular tuition at schools, or at least your family could teach you how to be both safe and sane on the road!)...
I'd be very happy if all bike riders were proper cyclists and road users - I'm actually not that happy with most "cycle paths" created as a sop to both road-wary bike users and cycle-unfriendly motorists). But while I will acknowledge that there's problem people on two wheels, I don't accept the premise that cyclists are intrinsically a problem, just the idiots of all kinds who don't do themselves or anyone else any favours. 20:16, 25 October 2022 (UTC)

hey, the image on this wiki is different from the image on the xkcd site now 15:24, 26 October 2022 (UTC)

Someone who can upload images will sort that out shortly (and then can add "This comic originall looked like <old image>" and the category for the comic having been changed). Looks like Randall took to heart it not having been clearly 50 hamsterball-people. ;) 20:12, 26 October 2022 (UTC)

Have a feeling that this comic is a parody of the recent renowed AI dawing of grenerating a picture by literal description. 07:40, 16 November 2022 (UTC)