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1619: Watson Medical Algorithm

2015-12-21T23:39:46Z

108.162.218.95: /* Transcript and Discussion of Medical Appropriateness */

{{comic
| number = 1619
| date = December 21, 2015
| title = Watson Medical Algorithm
| image = watson_medical_algorithm.png
| titletext = Due to a minor glitch, 'discharge patient' does not cause the algorithm to exit, but instead leads back to 'hunt down and capture patient'.
}}

==Explanation==
{{incomplete|much more on the different procedures etc.}}

IBM's {{w|Watson_(computer)|Watson}} is a natural language system designed to answer questions posed by humans. Recently, IBM has extended Watson to act as a {{w|clinical decision support system}}, using image analytics to aid physicians in medical decision making. In this comic, Randall shows a {{w|Flowchart|flowchart}} representing a possible algorithm for Watson, including bizarre techniques including surgical alteration of a patient to match a height and weight chart and squeezing the patient to remove yellow fluids. Like [[416: Zealous Autoconfig]], this comic pokes fun at a rigid, poorly-designed setup that ends up potentially doing more harm than good.

Modern medicine involves both standard processes and clinical judgement based around years of advanced training. An algorithm like this would have to be incredibly complicated in order to simulate the clinical judgement of a good doctor.

The algorithm depicted treats a patient as more of a machine or mechanical system than a living being, especially through decisions such as:

* Injecting oxygen into patients with low oxygen saturation, rather than treating the root cause
* Removing and inspecting a skeleton, then diagnosing the patient's condition with a bone count
* Dissecting a doctor "for parts" after consulting him or her for advice
* Removing extra limbs from a patient if the count is less than 100
* Determining whether the "build environment" of the patient is sane. This is most probably a reference to the configure script used in the {{w|GNU_build_system|GNU build system}}, which emits "checking whether build environment is sane" as one of its status messages.
* Rinsing the whole patient with a saline solution
* Removing organs from a patient regardless of response to an organ donation request

Other decisions appear to be entirely unrelated to the conditions upon which they are predicated:

* If the patient doesn't rate their pain on a scale from 0-10, sequence their genome, apply a {{w|tourniquet}}, and perform an {{w|autopsy}}
* If the patient's phone's battery is low, defibrillate until the battery is charged, sync photos, then administer general anesthesia
* If the patient is successfully comforted after an oxygen injection, check their medical history and apply skin grafts
* If green fluid is released from the patient, begin to cauterize
* If the patient has 100+ limbs, check their Vitamin D level

The title text implies that, if the patient is so lucky to ever reach one of the two places with the option "discharge patient," a minor glitch will cause to program to go back to the ''hunt down and capture patient'' option which thus force the patient and the program to repeat the process again in an infinite cycle, that will only end once the patient give another rating of their pain level than on the 0-10 scale. Then the program will start to sequence their genome then apply a tourniquet and finally perform an autopsy, on what will in the end for certain be a deceased patient, but maybe not when the autopsy began. This will finally cause the patient to leave the cycle... as a corpse!

This is one of many comics with [[:Category:Flowcharts|flowcharts]], amongst other a recent comic with that very name: [[1488: Flowcharts]].

This is the second comic in a row about health issues with the last comic being [[1618: Cold Medicine]].

The computer's behavior in this comic can be compared to the healthcare robot named Baymax in the movie {{w|Big Hero 6 (film)}}.

==Transcript and Discussion of Medical Appropriateness==
{{incomplete transcript}}
{| border=1
| | Step
| | Medically valid?
| | Conditions and following step
|-
| |
Draw Blood
| background-color:green |
Phlebotomy is a normal early step in the diagnostic process, but not as first and unconditional step
| |
Record patient’s name
|-
| |
Record patient’s name
| background-color:green |

OK
| |
Measure Patient’s height and Weight
|-
| |
Measure Patient’s height and Weight
| |
OK
| |
Consult Standard height/weight chart
|-
| |
Consult Standard height/weight chart
| |
OK
| |
Surgically adjust patient to match
|-
| |
Surgically adjust patient to match
| |
May be considered ethically dubious unless there are [http://www.gosh.nhs.uk/medical-information/procedures-and-treatments/limb-length-difference-and-limb-lengthening sound medical reasons] for doing so. Could be an allusion to [https://en.wikipedia.org/wiki/Procrustes Procrustes].
| |
Is patient coughing up blood?
|-
| width="33%" rowspan=2 |
Is patient coughing up blood?
| width="33%" rowspan=2 |
OK, coughing up blood is generally a sign that there is something wrong. Typical causes are respiratory tract infections (e.g. tuberculosis), lung trauma or pulmonary embolism.
| |
Yes: Gather blood and return it to body
|-
| |
No: Is patient still here?
|-
| width="33%" rowspan=2 |
Is patient still here?
| width="33%" rowspan=2 |
Not usually considered a step, but missing patients are a problem in some fields, psychiatry or intensive care for example.
| |
Yes: Record pulse rate
|-
| |
No: Hunt down and capture patient
|-
| |
Hunt down and capture patient
| |
Valid if patient should not have left the bed/unit, but the wording is possibly dubious.
| |
Is patient still here?
|-
| |
Gather blood and return it to body
| |
Dangerous idea in this case due to likelihood of contamination, although if safely done autotransfusion is an accepted medical technique to ensure a matching blood supply prior to a major operation, or to enhance stamina (blood doping)
| |
Record pulse rate
|-
| |
Record pulse rate
| |
OK, but maybe a little late.
| |
Is patient screaming?
|-
| width="33%" rowspan=2 |
Is patient screaming?
| width="33%" rowspan=2 |
Very important question, indicating patient is conscious, in pain, and aware pain is bad. First attenders can use it in classifying priorities (quiet patients may be more severely injured). Generally useful in assessing nerve damage, pain relief, etc.
| |
Yes: Ignore
|-
| |
No: Check blood O2 saturation
|-
|-
| width="33%" rowspan=2 ` |
Check blood O2 saturation
| width="33%" rowspan=2 |
Only really indicated if the patient is in danger of hypoxia. Generally normal people should have a SpO2 of 98-100%, but in chronic lung disease this can fall as low to 80%, and in premature babies a SpO2 of 90% is usually targeted to avoid problems with retinopathy. If the SpO2 were to fall as low as 50%, the patient would definitely be dead or unconscious.
| |
>50%: Remove and inspect skeleton
|-
| |
<50%: Inject oxygen
|-
| width="33%" rowspan=2 |
Remove and inspect skeleton
| width="33%" rowspan=2 |
Fatal if patient is still alive when beginning. Also not a valid medical procedure in any way as it is impossible to remove most of the long bones of the body without destroying all surrounding tissue.
| |
Too many bones: Is fluid coming out of patient?
|-
| |
Too few bones: Request consult with human doctor
|-
| |
Request consult with human doctor
| |
Medically valid in the context of obtaining an opinion from a doctor in a different speciality who is better suited to treating the patient.
| |
Dissect doctor for parts
|-
| |
Dissect doctor for parts
| | This may be considered ethically dubious. Possible reference to the Doctor Who episode “{{w|The girl in the fireplace}}”
| |
Discharge patient
|-
| |
Discharge patient
| |
Acceptable, but patient would generally be dead by then.
| |
END STATE (before you read the title text)
|-
| |
Is fluid coming out of patient
| |
Unintended fluid release is always a problem. How significant a problem depends on where the fluid came from and if it is supposed to be coming from there. Red generally is due to blood, yellow is due to pus/tissue fluid/lymph and green signifies bacterial infection or bile salts (biliverdin). Could also relate to normal fluids being lost (e.g. urine, saliva, sweat)
| |
|-
| |
Squeeze patient
| |
Could be in the medical context is in providing external ventilation (see iron lung) or other means of removing fluid (e.g. squeezing pus from a boil).
| |
Is fluid coming out of patient
|-
| |
What color?
| |
Never underestimate the number of different types of fluid the body can produce.
| |
|-
| |
Activate sprinklers
| |
Not medically valid. Presumably a reference to how much cleaning up will be required by this stage.
| |
Subdue patient
|-
| |
Subdue patient
| |
Potentially very important if patient is behaving dangerously to themselves and others around them (due to mental health issues e.g. psychosis or drugs) and/or is moving too much to be given treatment.
| |
Apply cream
|-
| |
Apply cream
| |
Medically valid as a form of barrier dressing to improve wound healing.
| |
Ask patient to rate pain level
|-
| |
Ask patient to rate pain level
| |
Useful in the sense that it provides the doctor with the means to ensure that the patient is receiving adequate analgesia during conditions of chronic and acute pain.
| |
|-
| |
Massage scalp
| |
This would belong more to the domain of palliative care and reflexology rather than being an accepted medical treatment.
| |
Patient is healthy
|-
| |
Patient is healthy
| |
A subjective assessment of the health patient is often helpful in ruling out certain diagnoses. For example, one is less likely to suspect cancer in a fit, healthy 30 year old than a thin, lethargic 50 year old.
| |
Admit for observation
|-
| |
Admit for observation
| |
Useful in the context of 'watchful waiting', in which the doctor may be unsure if the patient actually has a condition that they suspect that the patient has. By keeping the patient on the ward for a few days, the clinician can monitor the progression of symptoms and rapidly initiate adequate treatment if medically warranted.
| |
|-
| |
Laser eye removal
| |
This is not a standard medical procedure. This could be a pun on laser eye surgery where a laser is used to correct visual problems (e.g. short-sightedness), or laser hair and tattoo removal.
| |
Admit for observation
|-
| |
Sequence genome
| |
Useful in the association of extremely rare point mutations with an organic illness. See for instance the Genome 10K Project or the Cancer Genome Atlas. Or in diagnosing extremely rare mutations that are not picked up by most commercial DNA screening tests (e.g. kidney failure due to INF2 mutation).
| |
Apply tourniquet
|-
| |
Apply tourniquet
| |
Useful to stop acute bleeding from an injured extremity, but if it is drawn too tightly it can cause neuromuscular damage.
| |
Perform autopsy
|-
| |
Perform autopsy
| | Fatal if patient is still alive when beginning.
| | END STATE (taking the title text into account, the only possible one)
|-
| |
Inject oxygen
| |
May be fatal as injecting gases directly to the blood vessels can cause a serious embolism if it blocks blood flow to the brain or coronary arteries. However, if the oxygen is injected slowly into the venous circulation, it may be survivable as the bubbles may simply collect in the lungs where the oxygen is then slowly resorbed into the blood.
| |
Comfort patient
|-
| |
Comfort patient
| |
Psychological support to the patient and relatives is often useful after breaking news of a poor prognosis. It may also be useful in subduing the agitated or psychotic patient.
| |
Subdue patient
|-
| |
Review medical history
| |
Important early step, rather too late and conditional.
| |
Skin grafts
|-
| |
Skin grafts
| |
Only indicated if massive areas of the skin are damaged (typically due to burns)
| |
|-
| |
Count number of limbs
| |
Not really relevant in medicine, but may be of use to know the reason behind any missing or extra limbs on seeing the patient though a through review of the medical history will render this point moot. Probably a little late to be noticing this now.
| |
|-
| |
Remove extra limbs
| |
Medically indicated in cases of polymelia either due to cosmetic purposes or because the extra limbs pose a direct threat to the health of the baby.
| |
Subdue patient
|-
| |
Measure vitamin D
| |
Valid in diagnosis of bone related issues, for example if multiple or comminuted fractures were being counted as additional limbs/bones.
| |
|-
| |
Check whether build environment is sane
| |
Could be technical reference to the installation of the algorithm in the robot, or could relate to the sanity of:
* The robot doctor
* The patient undergoing this procedure (before or after reaching this part of the process)
* The person who programmed the robot to perform this flowchart
* The person who allowed this state of affairs to occur (I'm looking at you [[Black-Hat]])

NB: Whether the build environment is sane is irrelevant to the flowchart.
| |
Rinse patient with saline solution
|-
| |
Rinse patient with saline solution
| |
Tepid sponging may be indicated if the patient has a high fever. Could also refer to internally rinsing patient with saline solution i.e. providing intravenous sodium chloride to boost circulating volume or to perform peritoneal dialysis.
| |
|-
| |
Is patient phone battery low?
| |
Invalid in medical terminology, could be a technological metaphor for the patient's consciousness or stamina. "Your life-force is running out"
| |
|-
| |
Defibrillate
| |
Indicated in cases where there is ventricular fibrillation, and to a lesser extent in atrial fibrillation (chemical cardioversion with adenosine is usually preferred)
| |
Is patient phone battery low?
|-
| |
Sync photos from camera
| |
Definitely invalid. Could refer to the robot attempting to backup photos from a camera before attempting to repair it/attempting to back-up patient's consciousness.
| |
Administer general anesthesia
|-
| |
Administer general anesthesia
| |
Valid, but not at this stage. Only used when the procedure will invoke unnecessary distress or pain to the patient if they were to be awake beforehand.
| |
Discharge patient
|-
| |
Blood loss?
| |
Useful. Patient may die if this clinical sign is missed.
| |
|-
| |
Patient address changed?
| |
Useful to ensure that the organisation has current contact details for the patient in the event that they may need to contact the patient (e.g. to arrange further appointments)
| |
|-
| |
Request organ donation
| |
Generally done prior to registering an individual for a driving licence or to a medical practice, or to the relatives of the deceased if consent had not been acquired beforehand.
|Remove organs
|-
| |
Remove organs
| |
The only organs which can be safely removed from a living person without resulting in serious, chronic medical issues are the kidneys/lungs (only one can be removed), spleen, part of the liver (as long as one lobe is left it can regrow to its original size) and colon (usually consisting of the appendix only). With some serious lifestyle modifications, the pancreas, pituitary gland, frontal lobe of brain, half of the brain, adrenal glands, bladder and most of the gut can be removed. The heart can be removed from the body and replaced with an artificial pump for a few months at the most. However, such organ removals are only indicated if there is a genuine clinical need to do so due to the non-negligible risk of death associated with these operations.
| Discharge patient
|-
| |
Discharge patient
| |
| END STATE (before you read the title text)

|}

{{comic discussion}}

[[Category:Artificial Intelligence]]
[[Category:Flowcharts]]

526: Converting to Metric

2014-03-29T19:51:31Z

108.162.218.95: It clearly says bic pen not Big Penis.

{{comic
| number = 526
| date = January 5, 2009
| title = Converting to Metric
| image = converting to metric.png
| titletext = According to River, "adequate" vacuuming systems drain the human body at about half a liter per second.
}}
==Explanation==
Most people will eventually develop an intuitive feel for how big certain measurements are (e.g., how long an inch or a foot is, how much a pound weighs). This comic points out that people who were brought up using the {{w|Imperial measurement|imperial system}} probably don't have the same intuitive understanding for metric units and attempts to provide some benchmarks for these people. Most of the benchmarks are common sense, highly-useful ones (e.g., if it's 30 degrees centigrade [86°F], you'd be quite comfortable outside dressed for the beach) but some of the benchmarks are humorous and/or completely useless. Benchmarks include:

===Temperature===
* {{w|Extremes on Earth|Earth's Hottest}}: 60⁠℃ [140°F]: The hottest temperature recorded on earth is actually {{W|List_of_weather_records#Heat|"only" 56.7}}. There have been reports of ten-twenty degrees higher (70-80⁠℃) but these measurments ae not verified or accepted as world records.
* Various heat waves: {{w|Dubai}} is a city in the United Arab Emirates, and is smack-dab in the middle of an equatorial desert, so their heat waves can get ''hot!''. The southern Unites States will typically be a few degrees hotter than the northern United states simply because it's closer to the equator, but as mentioned they're both above "Beach Weather".
*30℃ [86°F]: A little too hot so perfect for a trip to the beach.
*20℃ [68°F]: Is defined as room temperature in many experimental settings. For some this would feel a little cool. But 25℃ [77°] would as mentioned be too warm for room temperature...
*10℃ [50°F]: Definitely wear a jacket. Especially if there is just a little breeze.
*0⁠℃ [32°F]: The freezing point of water (32°⁠F)
*-5 to -10℃: In Moscow -10℃ is not really that cold - it can go "spit goes clink" cold in {{W|Moscow#Climate|Moscow}}, whereas -5℃ [23°F] in {{W|Boston#Climate|Boston}} may be very cold...
*-20⁠℃: FuckFuckFuckCold and -30⁠℃ - Fuuuuuuuuuuuuck!: This is basically what some people would say when they step outside at this temperature. At -30⁠℃, without taking wind chill into account, exposed skin will feel painful in under a minute and frostbite could begin in as little as ten minutes [http://www.ec.gc.ca/meteo-weather/default.asp?lang=En&n=5FBF816A-1].
*-40⁠℃: Spit goes "clink": As shown in the drawing your spit would freeze ''before'' it hits the ground. This is the crossing point of the two temperature scales i.e. -40⁠℃ = -40°F.

===Length===
*1 cm [.4 inch] : Width of microSD card and 3cm - Length of SD card: Refers to the {{w|MicroSD card|memory cards}} used in cell phones, digital cameras, etc.
*12 cm [almost 5 inches]: CD rom are a common object so nice to know it is a dozen centimeters.
*14 cm [5 1/2 inches]: Most males would probably exaggerate the size of their penis, but 14-15 cm is very average.
*15 cm [almost 6 inches]: A Bic Pen
*80 cm [31 1/2 inches]: A typical doorway is also of standard size. This is barely over the minimum size typically required by codes for buildings [30 inches or 76.2 cm], but more than 50% over the size required for aircraft emergency exits. (It may seem illogical that larger doors are required in buildings than in airplanes, given airplanes are arguably more dangerous. However, there is no real disadvantage to using larger doors in buildings, which are not significantly pressurized, but using larger doors in aircraft would increase the force on the door caused by cabin pressure proportionally.)
*1 m [39.37 inches]: {{w|Lightsaber|Lightsaber Blade}}: Refers the weapon used in the {{w|Star Wars}} movie franchise. Canonically, the length of a Lightsaber's blade varies greatly depending on the setting of the weapon, but "one meter" is by no means a bad approximation.
*170 cm [5 feet, 7 inches]: {{w|Summer Glau}}: Refers to the height of the actress who portrays the character River Tam on the TV show {{w|Firefly (TV series)|Firefly}}.
*200 cm [6 feet, 6 and 3/4 inches]: Darth Vader: Refers to the height of the main antagonist from Star Wars.
*2.5 m [almost 10 feet]: Ceiling - of course very much depending on which type of building you are in!
*5 m [almost twenty feet]: Car Length - also very much depending on the car...
*16 m 4 cm: Human tower of Serenity crew: Again, this refers to the Firefly TV show, which takes place mostly on a space ship called Serenity.
**Presumably, if all the crew of Serenity were stacked on top of each other, this would be their combined height.
**The comic depicts four characters from the show standing on top of each other; the bottom figure is the crew's captain, {{w|Malcolm Reynolds}} in his signature coat. Judging from the other drawing of Summer Glau from the volume section, she is standing on top of the captain.
**The other five members of the crew should also be stacked on top of these four to reach the 16m height - giving them an average height of 1,82 cm (12 cm more than Summer Glaus height!)

===Speed===
:Here both the SI unit m/s as well as the more used unit kph is given.
*5 kph [3 mph] - 1.5 m/s: Walking at a normal pace
*13-25 kph [8-15 mph]: Jogging to sprinting.
*35 kph [21.75 mph] - 10 m/s: Fastest human: As of 2009, the fastest a human has been recorded to run in a single sprint is actually 45 kph, a record set by {{w|Usain Bolt}}.
*45-55 kph: Both cats and rabbits go much faster than normal people.
*75 kph [46.6 mph] - 20 m/s: Raptor: It's a comic written by Randal, of course a reference to the raptors from ''Jurassic Park'' was going to be here.
*100 kph - 25 m/s: A slow highway (62 MPH).
*110 kph [68.35 mph] - 30 m/s: Interstate (65 MPH): Refers to the {{w|Interstate|American highway system}}. (65 mph would actually be only 104.6 kph.)
*120 kph - 35 m/s: Speed you actually go when it says "65": People routinely break the aforementioned speed limit, and the police typically don't mind as long as it's not posing any danger. For the record, 120 kph is 74MPH.
*140 kph - 40 m/s: Raptor on Hoverboard: The Hoverboard is probably a reference to the ''Back to the Future'' series, though it's a fairly common trope in older science fiction stories.

===Volume===
*3 ml: The amount of blood in a fieldmouse.
*5 ml: A teaspoon - a very common measure.
*30 mL: Nasal Passages and 40mL - Shot Glass: The comic points out that you could just about fill a shot glass using the mucus from your nose. Since shot glasses are usually used for mixed drinks, the comic jokes that this mucus could constitute a new, disgusting drink - and this is depictured in the drawing.
*350 ml: Soda can (this is roughly correct for the cans used in the U.S., which hold 12 fluid ounces; in Europe, soda cans hold 500 ml).
*500 ml: Water bottle (this is the also the volume of a European water bottle).
*3 L: Two-liter bottle: Refers to a bottle which contains two liters (in the US usually soda). There is debate as to the reason for the discrepancy in volume.
*5 L: An adult male has about 5 L of blood in his body (An ''adequate'' vacuuming systems could drain this blood out in 10 s - as per the title text!)
*30 L: Milk Crate: Refers to a {{w|Milk crate|type of small box}} originally used to transport milk but now often in demand to be used as bicycle basket, storage spaces, etc.
*55 L: Summer Glau: Again, this refers to the actress from Firefly.
*65 L: {{w|Dennis Kucinich}}: An American politician belonging to the {{w|Democratic Party (United States)|Democratic party}}, noted for his relatively strong (for the US) leftist views.
*75 L: {{w|Ron Paul}}: An American politician belonging to the rival {{w|Republican Party (United States)|Republican party}}, noted for his strong rightist views.
*200 L: Volume of refrigerator.
*As shown in the drawing of this part of the comic, the three persons mentioned above - Glau, Kucinich and Paul (summing up to 195 L) - could in principle all fit inside a standard refrigerator. Cueball thus attempts to push them all inside of one - and from the above mentioned political views it would be clear, the two men would not at all get along together trapped inside a fridge.

===Mass===
*3 g: {{w|M&M's|Peanut M&M}}: A small chocolate candy with a peanut inside
*100 g: Cell phone - this very much depends on the age of the cell phone, and the type etc.
*500 g [1 lb.]: A bottle of water contains 500 ml according to the volume section and thus have mass of 500 g.
*1-3 kg: Different types of laptops. The newest and the best is the lightest...
*5 kg [11 lb.]: {{w|Lcd monitor|LCD Monitor}}: A modern flat-screen-style monitor.
*15 kg: {{w|CRT monitor|CRT Monitor}}: An older-style, cathode ray tube-based monitor.
*4 kg: Cat and 4.1 kg - Cat (With Caption): Refers to the internet's love of putting {{w|Lolcat|captions on cats}}. Usually, this is done in a graphics program, but here the cat is actually physically carrying around his caption. The "with caption" part is most likely a reference to [[262:_IN_UR_REALITY|Comic 262]], where [[Black Hat]] glues captions to cats, after running out of staples.
*60 kg [130 lb.]: Lady - for instance if she is Summer Glau - could be her again depicted in the comic - average weight of an adult woman.
*70 kg [150 lb.]: Dude - here depicted as Cueball who is the average guy, and 70 kg is average weight for an adult man.
*150 kg: Shaq: {{w|Shaq|Shaquille O'Neal}}, a famously tall basketball player.
*200 kg [440 lb.]: Your Mom
*220 kg: Your Mom (incl. 20 kg of cheap jewelry) and
*223 kg: Your Mom (also incl. 3 kg of Makeup)
*These last refers to a common type of {{w|Your mom}} joking insult whereby someone insults someone else's mother in a creative way. Here, the comic slyly calls your mom fat, then implies she wears way too much jewelry and finally also almost 7 pounds of makeup. This is a common theme in XKCD.

==Title text==
The title text refers once again to Summer Glau's Firefly character, River, who (after being subjected to a long series of medical experiments) is severely mentally ill and often comes out with macabre — though scientifically accurate — pronouncements.

==Transcript==
:Guide to Converting to Metric
:The key to converting to metric is establishing new reference points. When you hear "26 degrees centigrade", instead of thinking "That's 79 degrees fahrenheit" you should think, "that's warmer then a house but cool for swimming." Here are some helpful tables of reference points:

:Temperature:
:60 degrees centigrade - Earth's Hottest
:45 degrees centigrade - Dubai Heat Wave
:40 degrees centigrade - Southern US Heat Wave
:35 degrees centigrade - Northern US Heat Wave
:30 degrees centigrade - Beach weather
:25 degrees centigrade - Warm Room
:20 degrees centigrade - Room Temperature
:10 degrees centigrade - Jacket Weather
:0 degrees centigrade - Snow!
:-5 degrees centigrade - Cold Day (Boston)
:-10 degrees centigrade - Cold Day (Moscow)
:-20 degrees centigrade - FuckFuckFuckCold
:-30 degrees centigrade - Fuuuuuuuuuuck!
:-40 degrees centigrade - Spit goes "clink"
:[Stick figure next to last three lines.]
:Man: ''Pthoo'' [Man spits.]
:Spit: ''Clink!'' [Spit bounces off ground.]

:Length
:1cm - Width of microSD card
:3cm - Length of SD card
:12cm - CD Diameter
:14cm - Penis
:15cm - BIC pen
:80cm - Doorway width
:1m - Lightsaber Blade
:170cm - Summer Glau
:200cm - Darth Vader
:2.5m - Ceiling
:5m - Car-length
:16m4cm - Human tower of Serenity crew
:[Human tower of Serenity crew stick figures depicted taking up from second line of panel to bottom.]

:Speed
:5 kph - 1.5 m/s - Walking
:13 kph - 3.5 m/s - Jogging
:25 kph - 7 m/s - Sprinting
:35 kph - 10 m/s - Fastest Human
:45 kph - 13 m/s - Housecat
:55 kph - 15 m/s - Rabbit
:75 kph - 20 m/s - Raptor
:100 kph - 25 m/s - Slow Highway
:110 kph - 30 m/s - Interstate (65 MPH)
:120 kph - 35 m/s - Speed you actually go when it says "65"
:140 kph - 40 m/s - Raptor on Hoverboard

:Volume
:3mL - Blood in a fieldmouse
:5mL - Teaspoon
:30mL - Nasal Passages
:40mL - Shot Glass
:So when it's blocked, the mucus in your nose could about fill a shot glass.
:[Image of a shot glass.] Related: I've invented the worst mixed drink ever.
:350mL - Soda Can
:500mL - Water Bottle
:3L - Two-Liter Bottle
:5L - Blood in a Human Male
:30L - Milk Crate
:55L - Summer Glau
:65L - Dennis Kucinich
:75L - Ron Paul
:200L - Fridge
:[Cueball shoving Ron Paul, Summer Glau, and Dennis Kucinich into fridge.]
:[Above fridge, circled, is 55+65+75<200]

:Mass
:3g - Peanut M&M
:100g - Cell Phone
:500g - Bottled Water
:1kg - Ultraportable Laptop
:2kg - Light-Medium Laptop
:3kg - Heavy Laptop
:5kg - LCD Monitor
:15kg - CRT Monitor
:4kg - Cat [Drawing of cat.]
:4.1kg - Cat (With Caption) [Drawing of cat, going "Mrowl?", and holding a caption.]
:60kg - Lady
:70kg - Dude
:150kg - Shaq
:[Stick figure of Megan and Cueball beside previous 3 lines.]
:200kg - Your Mom
:220kg - Your Mom (incl. cheap jewelry)
:223kg - Your Mom (also incl. Makeup)

{{comic discussion}}
[[Category:Charts]]
[[Category:Comics featuring real people]]
[[Category:Comics featuring Megan]]
[[Category:Comics featuring Cueball]]
[[Category:Velociraptors]]
[[Category:Your Mom]]
[[Category:Firefly]]

1345: Answers

2014-03-21T11:17:13Z

108.162.218.95:

{{comic
| number = 1345
| date = March 21, 2014
| title = Answers
| image = answers.png
| titletext = Stanford sleep researcher William Dement said that after 50 years of studying sleep, the only really solid explanation he knows for why we do it is 'because we get sleepy'.
}}

==Explanation==
Cueball claims that humans are driven by their curiosity, which is never-ending. This appears to be a riff on the recurring philosophical question of what separates humanity from the rest of the animals. Jenny (unless I forget her name) answers this blanket statement by observing an apparent paradox: Everyone spends approximately eight hours per day in an unconscious state of sleep, but no one has yet discovered the biological purpose of sleep. This implies that every member of the human species is confronted daily with a mystery, yet no one "loses sleep over it"---that is, almost no one is distracted by this mystery. This implies that Cueball's observed curiosity has a perceptible and proximate limit.

It should be noted that many scientists are in fact busily investigating the reasons that humans sleep, although that inquiry has not resulted in satisfying answers. Some offered explanations are: to avoid nocturnal predators, to give the body a chance to repair itself, and to allow the brain a period to sort out long-term from short-term memories.

It should also be noted that "Which is why it keeps me awake all night" would have been a better punchline for Cueball than "touché."

The tooltip makes a semi-tautological statement that people sleep only "because we get sleepy." This is an example of question-begging, because getting sleepy only means that someone is feeling the urge to sleep. This may be an oblique reference to the French playwright Moliere [https://en.wiktionary.org/wiki/dormitive_principle], who created a satirical character who claimed to have discovered the answer to a popular question: The reason opium makes someone sleepy, said the character (a doctor), was that it contained a "dormitive principle" (i.e., something that makes someone sleepy).

==Transcript==
:[Cueball and Megan are talking.]
:Cueball: Humans are defined by our curiosity, our hunger for answer.
:Megan: We all spend a third of our lives lying down with our eyes closed and '''''NOBODY KNOWS WHY.'''''
:Cueball: Touché.

{{comic discussion}}

912: Manual Override

2014-03-09T19:30:58Z

108.162.218.95: /* Explanation */

{{comic
| number = 912
| date = June 15, 2011
| title = Manual Override
| image = manual_override.png
| titletext = I think you mean 'GNU Info Override'.
}}

==Explanation==
{{Incomplete|Wiki links are missing on further explain on man pages and GNU info pages. The real joke here is that the pilot has typed "MANUAL OVERRIDE" to manually override the plane's computer and steer the plane to safety, but instead ends up opening the manual page for "OVERRIDE". He did not intentionally open the manual page..}}

This comic makes fun of a trend in documentation for UNIX-like systems, specifically those that use the open source GNU toolchain.

Historically, UNIX systems had a way to access descriptions of the available programs: the "man" (from "manual") command. Typing "man program-name" would output a detailed text, called a "man page", describing the program's functionality, available command-line options, a list of related programs, etc. For many GNU-based programs, however, the output of "man program-name" will be very brief, mainly directing the user to invoke a GNU-specific information system (GNU Info), thus rendering the man page useless and annoying for the user.

In this comic, it appears that the plane's pilot is attempting to read the man page for the Emergency Override System, in an effort to land the plane safely. However, the Emergency Override System's man page has hardly any useful information at all, costing the pilot precious seconds he could be using to save the lives of his passengers. Instead of simply getting the information from the man page, the pilot has to go to the GNU info page for the override system. By the time he types the command in, it'll probably be too late.

==Transcript==
:[A plane is in a nosedive with smoke pouring from one wing. Text comes from someone reading in the cockpit.]
:"This is the emergency override system, which can be used to regain control of the aircraft.
:Complete instructions for activating this system are available as a GNU info page."

{{comic discussion}}
[[Category:Linux]]

350: Network

2014-02-20T22:10:55Z

108.162.218.95: Added the fact that Cueball wishes for welchia and Blaster to get along since part of welchia's payload was to remove Blaster.

{{comic
| number = 350
| date = November 28, 2007
| title = Network
| image = network.png
| titletext = Viruses so far have been really disappointing on the 'disable the internet' front, and time is running out. When Linux/Mac win in a decade or so the game will be over.
}}

==Explanation==
[[Cueball]] shows off his virtual fishtank of virus-infected {{w|Virtual machine|virtual}} Windows machines to [[Megan]]. The machines nominally have {{w|Trojan_horse_(computing)|mail trojans}}, {{w|Warhol worm}}s, all sorts of {{w|polymorphic virus}}es, and explicitly {{w|Blaster (computer worm)|Blaster}} and {{w|w32.welchia}}. Cueball relates to the viruses as though they are fish, and hopes that they are all getting along together nicely. This is because part of {{w|w32.welchia|welchia's}} malicious payload was to remove the {{w|Blaster (computer worm)|Blaster Worm}}
, effectively destroying it.

It would be possible to set up a virtual fishtank as described. The main issue would be to make sure that you don't accidentally let anything escape from the fishtank. Consider it like a smallpox lab. Also, some viruses are quite malicious and will prevent a computer from running normally, or at all. An aquarium of dead computers would not be very interesting to watch.

The first part of the title text refers to the difficulty viruses have in the common doomsday threat of "disabling the internet" as a whole. SQL Slammer had some brief success. The second part of the title text indicates that Randall believes A) that Linux and Mac OS X are inherently less vulnerable to virus attacks than Windows, and B) that Windows will become less important and disappear, so the virus writers had better get their act together soon.

It is not certain how justified this opinion is. Six years after this comic was written, Windows still dominates the desktop, and Linux and OS X are not ''that'' much harder to attack with viruses. A side issue is the wild growth in 'smart devices' connected to the internet, powered by non-traditional operating systems such as iOS and Android. Desktop operating systems such as Windows, Linux and OS X are ''all'' becoming less relevant (although note that Android is based on the Linux kernel), so both the operating system war and the struggle against computer viruses are still "anyone's game".

==Transcript==
:[Megan looking at a large screen with many green and red squares. The squares have writing in them and lines connecting them.]
:[Side view. The screen is a huge LCD connected to a wireless router.]
:Cueball: Pretty, isn't it?
:Megan: What is it?
:Cueball: I've got a bunch of virtual Windows machines networked together, hooked up to an incoming pipe from the net. They execute email attachments, share files, and have no security patches.
:Cueball: Between them they have practically every virus.
:Cueball: There are mail trojans, warhol worms, and all sorts of exotic polymorphics. A monitoring system adds and wipes machines at random. The display shows the viruses as they move through the network. Growing and struggling.
:[Cueball walks past the girl and touches the monitor.]
:Megan: You know, normal people just have aquariums.
:Cueball: Good morning, Blaster. Are you and W32.Welchia getting along?
:Cueball: Who's a good virus? You are! Yes, you are!

{{comic discussion}}
[[Category:Comics featuring Megan]]
[[Category:Comics featuring Cueball]]
[[Category:Comics with color]]

Talk:936: Password Strength

2014-02-11T15:17:27Z

108.162.218.95:

You still have to vary the words with a bit of capitalization, punctuation and numbers a bit, or hackers can just run a dictionary attack against your string of four words. '''[[User:Davidy22|{{Color|purple|David}}y²²]]'''[[User talk:Davidy22|<tt>[talk]</tt>]] 09:12, 9 March 2013 (UTC)

No you don't. Hackers cannot run a dictionary attack against a string of four randomly picked words.
Look at the number of bits displayed in the image: 11 bits for each word.
That means he's assuming a dictionary of 2048 words, from which each word is picked randomly.
The assumption is that the cracker knows your password scheme.
[[Special:Contributions/86.81.151.19|86.81.151.19]] 20:17, 28 April 2013 (UTC)
Willem

Sometimes this is not possible. (I'm looking at you, local banks with 8-12 character passwords and PayPal) If I can, I use a full sentence. A compound sentence for the important stuff. This adds the capitalization, punctuation and possibly the use of numbers while it's even easier to remember then Randall's scheme. I think it might help against the keyloggers too, if your browser/application autofills the username filed, because you password doesn't stand out from the feed with being gibberish. [[Special:Contributions/195.56.58.169|195.56.58.169]] 09:01, 30 August 2013 (UTC)

The basic concept can be adapted to limited-length passwords easily enough: memorize a phrase and use the first letter of each word. It'll require about a dozen words (you're only getting 4.7 bits per letter at best, actually less because first letters of words are not truly random, though they are weakly if at all correlated with their neighbors -- based on the frequencies of first letters of words in English, and assuming no correlation between each first letter and the next, I calculate about 4 bits per character of Shannon entropy). SteveMB 18:35, 30 August 2013 (UTC)

Followup: The results of extracting the first letters of words in sample texts (the {{w|Project_Gutenberg|Project Gutenberg}} texts of ''The Adventures of Huckleberry Finn'', ''The War of the Worlds'', and ''Little Fuzzy'') and applying a {{w|Entropy_(information_theory)|Shannon entropy calculation}} were 4.07 bits per letter (i.e. first letter in word) and 8.08 bits per digraph (i.e. first letters in two consecutive words). These results suggest that first-letter-of-phrase passwords have approximately 4 bits per letter of entropy. --[[User:SteveMB|SteveMB]] ([[User talk:SteveMB|talk]]) 14:21, 4 September 2013 (UTC)

Addendum: The above test was case-insensitive (all letters converted to lowercase before feeding them to the [[http://millikeys.sourceforge.net/freqanalysis.html frequency counter]]). Thus, true-random use of uppercase and lowercase would have 5 bits per letter of entropy, and any variation in case (e.g. preserving the case of the original first letter) would fall between 4 and 5 bits per letter. --[[User:SteveMB|SteveMB]] ([[User talk:SteveMB|talk]]) 14:28, 4 September 2013 (UTC)

I just have RANDOM.ORG print me ten pages of 8-character passwords and tape it to the wall, then highlight some of them and use others (say two down and to the right or similar) for my passwords, maybe a given line a line a little jumbled for more security. [[Special:Contributions/70.24.167.3|70.24.167.3]] 13:27, 30 September 2013 (UTC)
:Remind me to visit your office and secretly replace your wall-lists by a list of very similar looking strings ;) --[[User:Chtz|Chtz]] ([[User talk:Chtz|talk]]) 13:53, 30 September 2013 (UTC)

Simple.com (online banking site) had the following on it’s registration page:

“Passphrase? Yes. Passphrases are easier to remember and more secure than traditional passwords. For example, try a group of words with spaces in between, or a sentence you know you'll remember. "correct horse battery staple" is a better passphrase than r0b0tz26.”

Online security for a banking site has been informed by an online comic. Astounding.
[[Special:Contributions/173.245.54.78|173.245.54.78]] 21:22, 11 November 2013 (UTC)

The Web service Dropbox has an Easter egg related to this comic on their sign-up page. That page has a password strength indicator (powered by JavaScript) which changes as you type your password. This indicator also shows hints when hovering the mouse cursor over it. Entering "Tr0ub4dor&3" or "Tr0ub4dour&3" as the password causes the password strength indicator to fall to zero, with the hint saying, "Guess again." Entering "correcthorsebatterystaple" as the password also causes the strength indicator to fall to zero, but the hint says, "Whoa there, don't take advice from a webcomic too literally ;)." [[Special:Contributions/108.162.218.95|108.162.218.95]] 15:17, 11 February 2014 (UTC)