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Modes of Transportation

Title text: My bold criticism might anger the hot air balloon people, which would be a real concern if any of them lived along a very narrow line directly upwind of me.

Explanation

This explanation may be incomplete or incorrect: Created by a Transportationally convenient but insidiously dangerous robotic car - Please change this comment when editing this page. Do NOT delete this tag too soon.

Randall's chart compares different modes of transportation by how convenient and dangerous they are. At the top-left (high in convenience and low in danger) are airliners and trains, as these are both fast-moving vehicles on which many millions of dollars have been spent to make them safer. In the top-right, motorcycles are at the same convenience level, but are rated much more dangerous, since they are easy to lose control of at high speeds, and careless drivers (of cars) can easily hit a motorcycle and cause extreme harm. Things like unicycles (bottom-left) are considered much lower on the convenience scale, being not very fast or easy ways to travel, but relatively safe, while towards the centre, skis are apparently moderately convenient and moderately dangerous, since they are relatively easy to fall on if going fast downhill. Way out on their own in the bottom-right, hot air balloons appear to be unique in being rated least on convenience and highest on danger. Presumably, modes of transportation similar to hot air balloons (like zeppelins and blimps) are left off the chart to increase the gap for comedic effect.

Because a hot air balloon is rated so poorly, if an optimization algorithm considers it the optimal mode of transportation, it must be the result of a sign error (e.g. having a minus sign where a plus sign is supposed to be, or vice versa), making the algorithm optimize for the opposite result by mistake. This could be because, unusually, on the y axis of the chart higher is better, whereas on the x axis lower is better. If these were treated the wrong way around, it would result in the air balloon appearing to be the best result. More typically, you might plot convenience vs safety, so that a higher value on either axis would represent a better result. However, both measures are still likely to need to take underlying data (for safety, incident counts, etc.; for convenience, travel time, etc.) and invert them, leading to potential for errors.

In order to compare the relative danger from each mode of transport, one can look at statistics of fatalities and injuries sustained during each activity. Traditionally this can be reported in fatalities/KSI per mile driven or passenger mile (or other unit of distance), to account for the fact that some modes are used much more than others and make valid comparisons. They may also be reported per capita (but this ignores the relative usage of different modes), or per journey (but this doesn't take into account the fact that different modes typically have different journey lengths and times). All of these are somewhat flawed, since they are really measuring the danger to users of that mode of transport, both from their own conveyance, and from other sources such as other road users. Since ballooning is not a very common mode of transport, hot air balloon incidents are correspondingly uncommon, and flights are not routinely monitored or registered, it is difficult to draw strong conclusions from the data for hot air balloons.

The title text makes a joke that if a hot air balloon enthusiast disagrees with the ranking and is angered by it, they may wish to remonstrate or retaliate, but will have a difficult time getting to Randall's house with their preferred mode of transportation, because they are limited to travelling in the direction of the wind. If they chose an alternative form of transport, they would be making his point for him. In reality, hot air balloons have some freedom to choose their direction of travel, since by controlling their altitude they can access different wind directions at different heights. Randall should, therefore, be concerned about hot air balloonists who live within a wedge spanned by the various wind directions accessible on a given day. In principle, if the weather conditions are favorable, this could cover every direction from Randall's house. The phrase "hot air balloon people" is reminiscent of "autogyro people" from the title text of 1972: Autogyros.

Curiously, the comic includes most common forms of transport, and a number of less common ones, but omits examples such as buses (a mass transit solution arguably more convenient than trains). It is not clear if this is an error, or a deliberate choice to maintain the comic's layout and presentation.

This is the second comic in a row to feature an algorithm.

Transportation	Description	Convenience	Danger	Zone
Trains	Mass transit on rails, typically between urban centers.	Convenient and comfortable, provided proper funding/maintenance and filled timetables. Allows relatively cheap travel for many people at once.	Exceedingly safe, due to dedicated tracks along a controlled environment. Accidents are largely limited to individuals wandering onto the off-limit tracks.	Practicality
Airliners	Mass transit by aircraft	Extremely fast travel between population centers for larger groups of people. Less comfortable and more expensive than trains.	Extremely safe due to strong regulation and relatively little traffic interactions. However, the few catastrophies that do happen have high death counts.	Practicality
Cars	Motorised road vehicle Most common method of long distance travel, used by many individuals to reach specific destinations	Owners of a car can usually go easily to any road-accessible location within a 200 mile/300 km radius. Requires constant focus, but can transport a few passengers or some cargo.	Insides of cars are covered with safety features, because collisions are relatively common. Assuming appropriate speed limits and proper focus by the driver, accidents can largely be avoided. Cars are quite dangerous to nearby pedestrians.	Practicality
Scooters	Either: Kick scooter - Less convenient than the placing would suggest. Low powered motorbike/moped - More dangerous than the placing would suggest. Engine-powered scooter - A middle-ground.			Practicality
Bicycles	Human-powered (or mostly so) two-wheeled road vehicle	Assuming proper road connections, bicycles are highly accessibly for traveling to any location within a ~10 km radius, or further.	Bicycles mostly move slow enough for falls or collisions to have little impact, though they are vulnerable to motorized traffic where it shares the road.	Practicality
Boats	Watercraft of various types	Specialized for water traffic, which is a very common form of transportation. Quite comfortable, but usually very slow.	Sinking, whether by collision or misuse, can be lethal, especially on the sea. However, collisions are very rare.	Practicality
Walking	Personal bipedal ambulation	Can travel between any two connected points regardless of infrastructure, but only comfortable for a few kilometers. Very slow compared to even bicycles, but the energy intensity is good for exercise.	One of the safest way people get around, as long as you don't get hit by a motorized vehicle. Walking up or down stairs is particularly dangerous.	Practicality
Motorcycles	...			Speciality/Recreational
Helicopters	...			Speciality/Recreational
Light aircraft	In the United States, the general category of small aircraft covers a variety of aircraft certified to weigh 19,000 pounds (8618 kg) or less at takeoff. Maximum allowed weight varies by specific category.			Speciality/Recreational
Go-karts	...			Speciality/Recreational
Skateboards	...			Speciality/Recreational
Rollerblades	...			Speciality/Recreational
Skis	...		Downhill skiers can reach high speeds at which collisions could cause significant injury to the skier's lightly protected body. However, where they are being used as a mode of transport, rather than recreation, speeds would generally be much lower and safer.	Speciality/Recreational
Unicycles	...	Can be a practical form of transport for skilled riders, but similar limitations in range to bicycles.		Speciality/Recreational
Sleds		Useful in limited conditions which other forms of transport might struggle to cope with.		Speciality/Recreational
Bumper Cars		Only really convenient for making very short journeys.		Speciality/Recreational
Hot Air Balloons	...			?????

Transcript

This transcript is incomplete. Please help editing it! Thanks.

[A chart is shown, where the Y axis is labeled "Convenient for travel" and has an arrow pointing up and the X axis is labeled "Dangerous" and has an arrow pointing right.]

[The following modes are shown in the "Zone of practicality" (a large irregular area fitting in to the top left corner of the chart), highlighted with a gray background, starting with the first few bunched at highest convenience, :]

Trains [very convenient, very safe]

Airliners

Cars

Scooters [the most dangerous of this set, at medium-low danger]

Bicycles

Boats [medium-high convenience, a slight amount of danger]

Walking [the least convienient, at roughly half, and lowest danger of this set]

[The following modes are shown in the "Zone of specialty and recreational vehicles" (a large irregular swathe from the top right to the bottom left, not quite touching the prior zone), highlighted with a gray background, the nodes spread in rough order from high convenience/danger to low convenience/danger:]

Motorcycles [highly convenient, nearly maximum danger]

Helicopters [not quite fully convenient, most danger]

Light aircraft

Go karts

Skateboards

Rollerblades

Skis

Unicycles

Sleds

Bumper cars [lowest convenience and lowest danger item]

[The following is labeled "?????" (in the bottom right corner), and has a gray background all to itself in a small blob notably distant from the nearest other group:]

Hot air balloons [placed as almost the least convenient and most dangerous, of all labels]

[Caption below the panel:]

Hot air balloons are the optimal mode of transportation, if your optimization algorithm has a sign error.

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