Talk:2585: Rounding

2022-02-24T23:02:16Z

162.158.75.17:

Wot no {{w|FFF system|furlongs per fortnight}}? [[Special:Contributions/172.70.91.126|172.70.91.126]] 23:14, 23 February 2022 (UTC)

: I, too, was initially surprised that Randall hadn't used the standard joke measure. But, then I realized that F/F is so outrageously large that rounding wouldn't offer much advantage. [[User:MAP|MAP]] ([[User talk:MAP|talk]]) 05:10, 24 February 2022 (UTC)

If we're using the table, can I suggest it be fully filled in, but mark "original (rounded)" value cells one key colour and the chosen conversion in another, so that scanning along (not necessarily adjacent/rightwards) then down (always next row) then along... you see the 'bounce around'. And we also get to appreciate what other fractional values ''could'' have been chosen, prior to rounding... Alternately, some flow-charty layout (perhaps contained within a nominally borderless version of the table?) with arrows leading across the width and filling in-between each down-step. Ideas only. I have others, but those seem the best bet to consider. [[Special:Contributions/172.70.85.113|172.70.85.113]] 01:32, 24 February 2022 (UTC)

Disagree with the current (as of 23:27 US Eastern, 23 February) explanation. According to this site (https://ilovebicycling.com/average-bike-speed/), average downhill bike speed is over 45 mph. Since Cueball doesn't specify "on flat terrain", he should have no problem going 45 without exploiting imprecise conversions. [[User:Nitpicking|Nitpicking]] ([[User talk:Nitpicking|talk]]) 04:30, 24 February 2022 (UTC)
:Huh? This does not say average downhill speed is > 45, it says "fastest". Also why would Cueball need to do this bizarre rounding if he can actually go 45mph? This is an exaggeration because he can only go a typical speed of 17mph.[[Special:Contributions/172.69.33.145|172.69.33.145]] 04:52, 24 February 2022 (UTC)
::Fastest for average cyclist. -- [[User:Hkmaly|Hkmaly]] ([[User talk:Hkmaly|talk]]) 05:05, 24 February 2022 (UTC)
:As a cyclist of several decades experience, who has indeed attained such speeds on rare (reckless) occasions, I think that "fastest downhill speed for an average rider" is overstated. Maybe it is what average people are capable of on a well-surfaced, steep, straight, non-undulating road with sufficient vision (forward and of anything potentially moving into the road from the side) or at least confidence that you're not dealing with traffic/pedestrians/other unaware cyclists. Oh, and sufficient stopping distance for whatever brakes you have.
:Maybe everybody can do it ''once'', but a good bike-ride should be one you can walk away from at the end.
:(Also, that cycling-centric site might have a different idea of 'average' cyclist. The average person on a bike here can't even put their feet on the pedals correctly. If we're talking club-/competitive-cyclists (but still sub-pro) then I'd much more readily agree, but there are far more people these days who can't even ride on the roadway, it seems.)
:That bike, as drawn, looks like it'll be Okish (if kept well maintained) but not exactly set up as functional downhill racer, nor probably is the rider. I really think the machine probably could be ridden at 20+mph on the flat for as long as the rider can stand to, but the characterisation makes me not confident they're able to maintain that kind of average speed for a [https://www.cyclingtimetrials.org.uk/race-results/22059#anchor long ride], and I think they'd overbake a downhill speed-run too, or (sensibly) be more cautious. [[Special:Contributions/172.70.85.143|172.70.85.143]] 05:14, 24 February 2022 (UTC)
:: Yep - the speeds on that site are for road bikes. Cueball looks to be riding a hybrid (flat bars), which would tend to put him in a more upright position, creating a higher frontal area and air resistance, and so slowing his progress. That would have even more of an effect at higher speeds. [[Special:Contributions/162.158.159.43|162.158.159.43]] 11:14, 24 February 2022 (UTC)

Arguably, once you're up to numbers around 45, you're as likely, if not more so, to be rounding to the nearest 5 than the nearest unit (depending on context). So Cueball's initial statement could be taken as suggesting that he can ride at around 42.5 - 47.5mph (rather than 44.5 - 45.5mph). And if he could actually ride at over 45mph then he presumably wouldn't need to add the 'if you round' qualifier, so it could further be taken as just suggesting that he can exceed 42.5mph. [[Special:Contributions/162.158.159.43|162.158.159.43]] 11:22, 24 February 2022 (UTC)

Note I find it kind of disappointing that the insane "KPH" unit is used in the comic. Nobody uses that in places where speed is actually measured in km/h.

Ironically, by the same standards it only takes one conversion to say that he can't move at all on a bike. he goes 0 parsecs, lightyears or AU (for example) per year, decade or century (for example).

Can we remove the rounding errors in the "exact" values in the tables? For instance, the final value should be "45.0000" not "45.0001". In fact, all three values ending with 0001 are rounding errors. (These were probably a result of converting to metric and back, using low precision conversion factors.) [[User:Divad27182|Divad27182]] ([[User talk:Divad27182|talk]]) 15:49, 24 February 2022 (UTC)

Whoever decided to display that information in that table deserves an award. Gg. [[Special:Contributions/172.70.126.65|172.70.126.65]] 16:38, 24 February 2022 (UTC)

It's nice how the rounding of exact half-integers only ever has to deal with odd-numbers-and-a-half, so Cueball can't be charged with violating the "round to even" rule, nor with violating the "round away from zero" rule. [[Special:Contributions/172.70.131.122|172.70.131.122]] 18:06, 24 February 2022 (UTC)

It looks like Randall picked a starting speed (within a reasonable bike-riding range) to maximize his gain. Groups of starting speeds round to the same final speeds, and some groups have a higher maximum speed earlier in the rounding chain:
::{| class="wikitable"
! Start Speed
(mph)
! Max Speed
(rounded to mph)
! Final Speed
(mph)
|-
|1
|1
|0
|-
|2 to 9
|9
|8
|-
|10
|10
|8
|-
|11 to 16
|16
|15
|-
|17 to 45
|45
|45
|-
|46 to 54
|54
|53
|}[[Special:Contributions/172.70.131.122|172.70.131.122]] 21:24, 24 February 2022 (UTC)
:Are you assuming the exact same chain of conversions, just with different input values? Surely if he'd chosen to start at (say) 16, he'd have chosen whatever ''other'' chain of conversions would have sent him towards some decent high-value. Might have differed only by the initial conversions before it found itself landing on the same late-path, or could be completely different (to get to a different end) as the biased random-walk of choices hit a different useful stride pattern. [[Special:Contributions/141.101.99.20|141.101.99.20]] 22:39, 24 February 2022 (UTC)
::Yes, I put different starting speeds into the same conversion chain. Perhaps I should have said "He chose a reasonable starting speed and chain of conversions to maximize the gain." I was initially surprised that starting at 16mph ends at 15mph, then decided to plot it. The grouping of ending speeds also surprised me, but in hindsight that's to be expected with multiple round offs. [[Special:Contributions/162.158.75.17|162.158.75.17]] 23:02, 24 February 2022 (UTC)

A note about the propulsion system in the mouseover text: This system is not entirely novel and was first proposed by Douglas Adams who suggested using the notebooks of waiters in bistros to achieve the desired precision loss. He suggested it should be possible to achieve speeds of round ∞kph (∞mph)

80: My Other Car

2022-01-21T03:44:14Z

162.158.75.17:

{{comic
| number = 80
| date = March 24, 2006
| title = My Other Car
| image = other_car.jpg
| titletext = It's much better than the other one.
}}

==Explanation==
This comic refers to a popular form of {{w|bumper sticker}} that follows the template "my other car is a ____." Sometimes the blank is a fancy vehicle like a {{w|Porsche}} or a {{w|Ferrari}}; sometimes it's related to the person's job (e.g. "My other car is a fire truck"); sometimes it's an even more expensive form of transportation like a "{{w|yacht}}" or "{{w|private jet}}," or even something joking or in fiction (like a "{{w|TARDIS}}").

The premise was to jokingly imply that someone driving in a less fancy vehicle was wealthier than they looked, as they could afford a fancy car (they simply chose to drive the clunker that day). The designer of the first stickers might even have intended them for serious use by wealthy drivers. The form of sticker ultimately became so well known that the phrase entered the pop-culture lexicon.

Due to their popularity, these stickers also have been parodied in various ways, like the one [[Randall Munroe|Randall]] has invented here. Randall's sticker is a more "honest" sticker that admits "this IS my other car;" in other words, this is the nicer of the two cars.

This sticker could probably be used on an expensive car to mirror the traditional sticker's use on a cheaper car. However, the car in the strip is a Mitsubishi, which is not a particularly expensive brand. Thus it appears that Randall is using the sticker for contrasting purposes: while others would drive a modest car but joke that they have a really nice one at home, Randall's car is modest, and, as he noted in the title text, his other one is much worse than this one.

It's also possible that this is a play on meta-levels; by definition, the car that you're driving can't be your other car, as it's your car you're driving now. Your other car is the one sitting at home.

==Transcript==
:[The back of a blue Mitsubishi with a spoiler is shown.]
:Bumper sticker: This '''<big>IS</big>''' my other car.

{{comic discussion}}
[[Category:Comics with color]]

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Talk:2585: Rounding

80: My Other Car