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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. Parking, maintenance, and infrastructure requirements are often ignored when judging car convenience.	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. Driving is the most dangerous thing most people do, and cars are very dangerous to nearby pedestrians and cyclists.	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.	Kick scooter-style vehicles are probably less convenient than bicycles as they do not provide seating, and are less efficient at converting energy into motion. A low-powered motorbike is about as convenient as a bicycle, requiring refueling in lieu of pedalling, and going much faster.	Kick scooters are much slower – and therefore safer – than bicycles. A motorized scooter can exceed bicycle speeds, but falling might be slightly safer. Low-powered motorbikes often go much faster than bicycles, and would therefore be much more dangerous. All leave the rider vulnerable to danger from motorised traffic sharing the same space.	Practicality
Bicycles	Human-powered (or mostly so) two-wheeled road vehicle	Assuming proper road or trail connections, bicycles are highly flexible 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, and are often perceived to be much more subject to danger than they really are.	Practicality
Boats	Watercraft of various types	Specialized for water traffic, which is a very common form of transportation. Quite comfortable (unless you suffer from seasickness), but usually very slow.	Sinking, capsizing, or falling overboard, 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 most people only find it comfortable for a few kilometers. Very slow compared to even bicycles, but the energy intensity is good for exercise.	Most danger to those walking comes from others, such as being hit by a motorized vehicle. Has the potential for trip injuries, and walking up or down stairs is particularly dangerous, since a greater fall can result.	Practicality
Motorcycles	...	As practical as cars to move between locations, and sometimes quicker, due to the ability to filter in traffic, but generally less comfortable, especially in rough weather.	Cars with all the safety features of bicycles. Exceedingly dangerous at higher speeds, especially when sharing the road with cars.	Speciality/Recreational
Helicopters	Rotorcraft in which lift and thrust are supplied by horizontally spinning rotors.	Effective to move between any two points as long as there are landing pads of reasonable size. Can be used to hover relatively still in the air. Speed for utility helicopters is comparable to trains. Very loud, and very difficult to learn to fly.	As per Harry Reasoner: "An airplane by its nature wants to fly, and if not interfered with too strongly by unusual events or by a deliberately incompetent pilot, it will fly. A helicopter does not want to fly. It is maintained in the air by a variety of forces and controls working in opposition to each other, and if there is any disturbance in this delicate balance the helicopter stops flying; immediately and disastrously. There is no such thing as a gliding helicopter."	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	...	A lack of proper suspension makes for a bumpy ride, poor clearance would leave them at risk of grounding on more uneven terrain, and the maximum speed is quite low.	Crashing is much more likely to cause spinal damage than bicycles, but the relatively low speed would make them much safer than other motorized vehicle options.	Speciality/Recreational
Skateboards	A board on four wheels	Much slower and less energy-efficient than bicycles.	As long as you're not doing mad tricks in a quarterpipe, using a skateboard for transportation carries little risk, other than being struck by other users of the same space. Safety gear is common.	Speciality/Recreational
Rollerblades	Shoes with a single line of wheels at the bottom	Much slower and less energy-efficient than bicycles.	As long as you're not doing mad tricks in a quarterpipe, using rollerblades for transportation carries little risk, other than being struck by other users of the same space. Safety gear is common.	Speciality/Recreational
Skis	Narrow strips of material to stand on while sliding across a low-friction surface	A fine way to move downhill relatively fast, but maintenance of the slope is required. Also a fairly quick way to travel on the flat when there is snow cover that would make other modes of transport challenging. Less useful in less conducive conditions.	Downhill skiers can reach high speeds at which collisions could cause significant injury to the skier's lightly protected body. It can be hard to control your speed at lower skill levels, but as long as low speeds are maintained (as it might when used as a transportation option), skiing is not that dangerous.	Speciality/Recreational
Unicycles	One-wheeled human-powered vehicle	Can be a practical form of transport for skilled riders. Because unicycles lack a gear system, they are less mechanically efficient than bicycles and have a much lower top-speed.	Because of the lower top-speed, unicycles would be safer than bicycles, though you may fall off it more frequently.	Speciality/Recreational
Sleds	A construction that can slide over snow, ice, or sand	Useful in limited conditions in which other forms of transport might struggle to cope with.	It is hard to properly control your speed downhill, but extremely safe on level terrain or slight slopes.	Speciality/Recreational
Bumper Cars	Small electric karts with rubber bumpers	Only really convenient for making very short journeys. Typically require an electronic mesh in the ceiling to move at all.	Apparently safe enough to be a hardly-supervized children's entertainment attraction.	Speciality/Recreational
Hot Air Balloons	A basket tied to a huge bag of heated air	Provide limited control and low speeds. They were the only form of air-travel available in the 19th-century, but were overtaken by powered air-travel.	A malfunction in the balloon can result in a very rapid descent, from great height. A poorly executed descent could result in a mid-air collision (e.g. with trees, powerlines, etc.) with potential for a nasty fall.	?????

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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