https://www.explainxkcd.com/wiki/api.php?action=feedcontributions&user=199.27.128.87&feedformat=atomexplain xkcd - User contributions [en]2019-07-22T10:36:10ZUser contributionsMediaWiki 1.30.0https://www.explainxkcd.com/wiki/index.php?title=Talk:406:_Venting&diff=90767Talk:406: Venting2015-04-24T03:53:48Z<p>199.27.128.87: </p>
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<div>With the psychology of XKCD readers in mind, I thought I'd look around for real-life applications of this self-same snippet. To quote the meme: "I was not dissapoint!", although to wildly varying effectiveness and with grossly variable style.<br />
From among ''many'', I present a meagre and random selection, thus: [http://www.bbc.co.uk/ouch/messageboards/F2322274?thread=5276607&skip=40] [http://www.venganza.org/2008/08/wtf-is-wrong-with-you-ppl/comment-page-11/] [http://answers.yahoo.com/question/index?qid=20090408064430AA6kC66]<br />
:Ugh. None of those actually have sections containing the documentations that they are citing. I've been wanting to do one of those kinds of posts myself as I'm actually prone to typing out several paragraphs and including citations when I get dragged into an Internet argument. [[Special:Contributions/108.162.238.117|108.162.238.117]] 07:14, 19 January 2014 (UTC)<br />
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(...and remember to check out... what is there currently worth watching right now..? Well, check it out, whatever it is.) [[Special:Contributions/178.98.31.27|178.98.31.27]] 12:43, 18 June 2013 (UTC)<br />
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I'm not saying that the explanation is wrong (well, part of it [http://en.wikipedia.org/wiki/Almost_surely almost definitely] is), but I'm not sure that the use of Summer Glau's name is to get the last word. The kind of person that you would use this type of critical analysis on would be unlikely to be a nerd (re: grammar/syntax/spelling/capitalization errors and lack of understanding of the subject involved), but an Internet troll or general idiot. So what would be the point of using that name? My initial impression was that it was giving the appearance of hidden depths to a celebrity (who may or may not be seen as capable of it), and would thus illicit an amusing reaction from the reader. Imagine if you saw a word-by-word rebuttal attributed to Paris Hilton or Justin Beiber. An alternate interpretation is that it would make a favored celebrity look even better, much like the "memetic badass" status that Chuck Norris[http://en.wikipedia.org/wiki/Chuck_Norris#Internet_meme] has.<br />
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[[Special:Contributions/108.162.238.117|Barack Obama]] 7:14, 19 January 2014 (UTC) P.S. Don't forget to vote!<br />
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I edited the almost surely wrong part, but this explanation still needs some work by a native English-speaker. [[Special:Contributions/141.101.97.215|141.101.97.215]] 07:05, 23 April 2014 (UTC)<br />
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I'm not sure if this is so much about people losing the chance to sleep with Summer Glau. Could it be more about the character of River in Firefly, who would presumably be the kind of person to write a blog comment like this? [[Special:Contributions/199.27.128.87|199.27.128.87]] 03:53, 24 April 2015 (UTC)</div>199.27.128.87https://www.explainxkcd.com/wiki/index.php?title=Talk:1316:_Inexplicable&diff=84393Talk:1316: Inexplicable2015-02-12T16:00:52Z<p>199.27.128.87: lulz</p>
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<div>[http://xkcd.com/725/ Literally] haunted? [[Special:Contributions/173.245.53.152|173.245.53.152]] 08:22, 13 January 2014 (UTC)<br />
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I was wondering too if Randall was also taking a sideways swipe at the way many people today misuse the term "literally".[[Special:Contributions/108.162.216.30|108.162.216.30]] 22:42, 13 January 2014 (UTC)<br />
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I would say he trying to say that some errors that computers have are impossible to fathom. I've baffled our IT people on many an occasion and the solution is usual 'rebuild' which is the computer equivalent of an exorcism.[[Special:Contributions/108.162.231.228|108.162.231.228]] 10:18, 13 January 2014 (UTC)<br />
:Definitely this. It is also much harder to figure out what the problem is with a computer when you weren't the one who has spent all their time using the computer. It is why I can't understand how IT people do their jobs. [[User:Daleb|Daleb]] ([[User talk:Daleb|talk]]) 13:14, 13 January 2014 (UTC)<br />
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Surprised nobody mentioned [https://en.wikipedia.org/wiki/Ghost_in_the_machine Ghost in the machine] yet... --[[User:Koveras|Koveras]] ([[User talk:Koveras|talk]]) 10:28, 13 January 2014 (UTC)<br />
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I find the current explanation entertaining but... raises questions.<br />
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Is "This comic is inexplicable and represents a self-referencing joke about explainxkcd.com." serious?<br />
:I think it's not and I deleted the sentence. [[Special:Contributions/173.245.50.84|173.245.50.84]] 14:39, 13 January 2014 (UTC)<br />
:: If the comic is not a self-referencing joke about explainxkcd.com, then what conceivable combination of words WOULD constitute such a joke? (note: I am not the one who first made the (now deleted) point, but I agree with it.) [[Special:Contributions/108.162.231.214|108.162.231.214]] 08:46, 14 January 2014 (UTC)<br />
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"While it might [be] a reasonable conclusion [i.e. that it is 'haunted'] for a human, demons can't possess a computer." - this reads like "demons exist, but are incapable of possessing computer equipment", rather than "demons cannot possess a computer, because they don't even exist", which would be my ''preference'' (under the standard rules of not being able to ''prove'' the non-existence of the supernatral... and, believe me, I've had my fair share of totally baffling computer problems, in my time, and often anthropomorphise equipment, somewhat, ''at least'' to explain it to non-tech users... but then end up adopting the same attitude myself, of course).<br />
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"The title text suggests that Megan insists that Cueball resume possession of his laptop, as she is unsettled by the ghost; Cueball simply refuses, seeing an opportunity to make his problem hers." - I see that as more akin to the "cursed gem" type of story. One simply cannot palm the gem off on somebody else, but it must have a legitimately willing recipient (including a thief stealing it, often) in order for the curse itself to transfer itself. Now that the 'status' of the laptop is known he's not going to accept it back and take the 'curse of errors' back upon himself. [[Special:Contributions/141.101.99.223|141.101.99.223]] 14:08, 13 January 2014 (UTC)<br />
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:I just removed the sentence "While it might [be] a reasonable conclusion for a human, demons can't possess a computer." In the real world ghosts (the comic does not mention demons) don't exist and can't possess either humans or computers; in a fictional world, they might be able to do either or both (a la King's "Trucks"). -- [[Special:Contributions/108.162.212.217|108.162.212.217]] 15:24, 13 January 2014 (UTC)<br />
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::Are you completely sure of that? How do you look at news like [http://www.independent.co.uk/news/world/europe/catholic-church-trains-more-priests-to-perform-exorcisms-9046578.html|Catholic Church trains more priests to perform Exorcism]? -- [[User:Hkmaly|Hkmaly]] ([[User talk:Hkmaly|talk]]) 11:12, 14 January 2014 (UTC)<br />
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I think the joke is just that normally the smartass that knows more about computers than you is able to easilly fix it, but not in this case. [[User:Halfhat|Halfhat]] ([[User talk:Halfhat|talk]]) 16:13, 13 January 2014 (UTC)<br />
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So am I the only one who thinks that the caption(or whatever the hover over text is called) refers to Cueball trying to return the laptop to a retail store. I mean I can see a store like Best Buy refusing to take back a laptop because a customer insists that there is a ghost in it. [[Special:Contributions/108.162.216.83|108.162.216.83]] 18:25, 13 January 2014 (UTC)<br />
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:I agree. but until more people notice it, lets leave it. [[User:Imanton1|Imanton1]] ([[User talk:Imanton1|talk]]) 03:56, 14 January 2014 (UTC)<br />
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:I thought this too, except I thought it was more a comment on people's attachment to technology, "Demon-posessed or not, it's got all my kitten videos on it!".--[[Special:Contributions/141.101.98.230|141.101.98.230]] 08:28, 14 January 2014 (UTC)<br />
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:You're not the only one. That's exactly what I thought the mouseover text was about, too. I guess it could be read multiple ways, but maybe the explanation should acknowledge that? [[User:Enchantedsleeper|Enchantedsleeper]] ([[User talk:Enchantedsleeper|talk]]) 19:12, 15 January 2014 (UTC)<br />
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Overthinking, maybe, but if the computer is haunted (read: possessed), then a valid solution IS to return (read: unpossess? dispossess?) it. [[Special:Contributions/108.162.216.57|108.162.216.57]] 23:36, 13 January 2014 (UTC)<br />
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Demons and devils can possess people or things; ghosts only loiter/haunt a location.{{unsigned ip|108.162.216.30}}<br />
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My wife says, "it's a Turing test!"<br />
[[Special:Contributions/108.162.219.199|108.162.219.199]] 02:24, 14 January 2014 (UTC)<br />
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Am I the only who have thought of a corrupted random access memory on this laptop? Last time when I had a RAM failure on one of my machines, for a non technical person it may have appeared haunted: e.g. not executing just specific applications, writing nonsensical error messages, crashing applications when a specific word was being used...you name it. Running memcheck revealed later that one RAM module had lots of corrupted bytes but the problem only appeared when one RAM module was getting hot. So as long as the machine was idling if behaved just fine. So no ghost for me, I guess. [[Special:Contributions/108.162.231.217|108.162.231.217]] 09:19, 14 January 2014 (UTC)<br />
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People, there is no implication that this is a new laptop. It cannot be returned to the store, ok? Megan does not want it in her possession, so she wants to give it back to Cueball but he will not accept it. The only reason she says "take it back" is because it this a straight line that allows Cueball to reply "No". [[Special:Contributions/108.162.219.223|108.162.219.223]] 18:33, 14 January 2014 (UTC)<br />
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I once had a computer that was a nudist. After a couple of months it allowed me to get it dressed. I must say it taught me to be more accepting of the needs of electronic devices then and now. [[Special:Contributions/199.27.128.186|199.27.128.186]] 20:02, 14 January 2014 (UTC)<br />
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I'm not convinced that the strip is genuinely inexplicable, but one thing I am certain of is that there is no explanation to be found here on this page. None. Every single one of the comments above is reaching. If the computer is literally haunted, then describing it as such is not misuse of the term "literally". If there's no terminological misuse, then there's no sideswipe at the misuse. Maybe some computer errors are impossible to fathom, but describing such errors as a 'haunting' does not constitute a joke, etc., etc., etc. To me the key, the "punchline", is Cueball's "told you". That is the only thing that requires explanation. All the stuff above is annotation, NOT explanation. Q: When did Cueball tell Megan that the computer was haunted? A: When he told her that "nothing works or makes sense". To him the two statements, "the computer is haunted" and "nothing works or makes sense" are equivalent. To him haunting can only be a valid explanation in a world which is entirely devoid of logic. I did try to explain that, but my explanation got Occam's-Razored out of existence. [[Special:Contributions/141.101.98.225|141.101.98.225]] 03:14, 15 January 2014 (UTC)<br />
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:Yes, my comment about the use of "literally" _was_ meant as an amused remark at best, not explanation. Otherwise I would not have put it on the discussion page :) [[Special:Contributions/173.245.53.152|173.245.53.152]] 15:34, 15 January 2014 (UTC)<br />
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Did anyone else think of the Buffy the Vampire Slayer episode "I Robot, You Jane"? It could be a reference (Giles: ... There's a demon in the Internet. Ms. Calendar: I know.) [[User:Yuriy206|Yuriy206]] ([[User talk:Yuriy206|talk]]) 17:57, 16 January 2014 (UTC)<br />
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"Ghost" was also a popular disk cloning and backup software. And restoring from a clean "ghost image" is a common way to fix "haunted" computer. --[[Special:Contributions/108.162.231.123|108.162.231.123]] 17:08, 27 January 2014 (UTC)<br />
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I think it's so funny that nobody has mentioned that 1316 is a Windows error code for a network error during an install that can be quite irritating to try and fix/diagnose esp if you are offline/not part of a network with resources. [[Special:Contributions/199.27.128.87|199.27.128.87]] 16:00, 12 February 2015 (UTC)</div>199.27.128.87https://www.explainxkcd.com/wiki/index.php?title=Talk:1477:_Star_Wars&diff=83345Talk:1477: Star Wars2015-01-23T19:23:19Z<p>199.27.128.87: </p>
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<div>Hope the transcript matches normal presentation mores. And I thought I'd keep the title text explanation simple - so I haven't wasted much time if it gets utterly changed. [[User:Mattdevney|Mattdevney]] ([[User talk:Mattdevney|talk]]) 12:55, 23 January 2015 (UTC)<br />
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Does anyone else notice a weird white line through the dates? [[User:Djbrasier|Djbrasier]] ([[User talk:Djbrasier|talk]]) 14:39, 23 January 2015 (UTC)<br />
:I came here to ask about that. [[User:Linea alba|Linea alba]] ([[User talk:Linea alba|talk]]) 16:13, 23 January 2015 (UTC)<br />
::Haha, your username is linea alba. [[Special:Contributions/199.27.128.87|199.27.128.87]] 19:23, 23 January 2015 (UTC)<br />
:Same here. I'm wondering if it's stylistic somehow (futuristic-looking?) or just a mistake.--[[User:Piratejabez|Piratejabez]] ([[User talk:Piratejabez|talk]]) 17:26, 23 January 2015 (UTC)<br />
::It looks as if he tried to move the labels down, but didn't select the whole line: [http://imgur.com/a/EZSYT]. But it seems odd that he wouldn't notice it right away, since it cut ALL the digits in half. [[User:Linea alba|Linea alba]] ([[User talk:Linea alba|talk]]) 18:47, 23 January 2015 (UTC)<br />
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If anyone's interested, I just used http://timeanddate.com to calculate the Star Wars Trilogy Tipping Point, i.e.- the date starting on which ''The Phantom Menace'' will have released closer to ''A New Hope'' than to the present day: May 13, 2021. --[[Special:Contributions/173.245.50.140|173.245.50.140]] 18:23, 23 January 2015 (UTC)</div>199.27.128.87https://www.explainxkcd.com/wiki/index.php?title=Talk:1463:_Altitude&diff=81259Talk:1463: Altitude2014-12-23T00:17:13Z<p>199.27.128.87: </p>
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<div>Ok, Is everyone on vacation today? or is this explanation that hard? [[User:Edo|Edo]] ([[User talk:Edo|talk]]) 19:27, 22 December 2014 (UTC)<br />
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: The comic was uploaded just minutes before you commented at 19:23. [[User:ThePurpleK|ThePurpleK]] ([[User talk:ThePurpleK|talk]]) 19:36, 22 December 2014 (UTC)<br />
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: "Ok, Is everyone on vacation today?" Randall was ... --[[User:RenniePet|RenniePet]] ([[User talk:RenniePet|talk]]) 20:01, 22 December 2014 (UTC)<br />
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Transcript right now assumes two Astronomers. It looks to me like three. [[Special:Contributions/173.245.52.142|173.245.52.142]] 21:03, 22 December 2014 (UTC)<br />
:I changed it to 3. [[Special:Contributions/108.162.221.201|108.162.221.201]] 22:36, 22 December 2014 (UTC)<br />
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A [http://en.wikipedia.org/wiki/Laser_guide_star laser guide star] is a device for focussing telescopes. [https://www.youtube.com/watch?v=vcjB2qN0TxM Cats go crazy chasing lasers]. I can only imagine what havoc a star cat might wreck chasing a laser guide star. [[Special:Contributions/108.162.216.40|108.162.216.40]] 21:07, 22 December 2014 (UTC)<br />
: The source of the laser is only moving at 1000 miles an hour, but it's going in a huge circle. That's a lot of leverage for our particular lighthouse. {{unsigned|Seebert}}<br />
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I may be wrong, but I think all high-altitude observatories are built on mountaintops. So the drawings indicating the astronomers are driving up a hill, at least for the last stretch, is wrong - they'd be driving up a very steep mountain road with lots of zig-zags. --[[User:RenniePet|RenniePet]] ([[User talk:RenniePet|talk]]) 23:49, 22 December 2014 (UTC)<br />
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True story: Stephan James O'Meara's eyeballs are close to where it'd become statistically unlikely for there to be humans with a more perfectly shaped eyeball. He probably sees that 3 of the sky's planets are bigger than a point without an instrument. So from natural ability, being born after '55, and a bit from practice, SJO had about the best night vision of anyone alive in 1985. The guy wanted to be the first human to see Halley's Comet come back. So he traveled from Boston to a 14,000 foot volcano in the middle of the Pacific and brought a telescope so wide that Yao Ming could barely hug it. And bottled oxygen. Even people who can grow enough blood cells and heart-lung athleticism to acclimate completely still have trouble seeing in the dark. Besides some of the best observing conditions on the planet, it was also only 7.5 degrees from the latitude where Halley's Comet passed overhead so there was very little extra air to look through. Also, you have to use peripheral vision. But not too far to the side. And not the ear side, that's the blind spot. And tap the telescope and look for motion. That's the technique. It must've been freezing (it was midwinter and convection of even a human under the opening affects the view) but here is a guy staring through a telescope Yao Ming could barely get his arms around with an oxygen mask to his face. [[Special:Contributions/199.27.128.87|199.27.128.87]] 00:17, 23 December 2014 (UTC)</div>199.27.128.87https://www.explainxkcd.com/wiki/index.php?title=Talk:509:_Induced_Current&diff=71996Talk:509: Induced Current2014-07-20T08:14:25Z<p>199.27.128.87: Start discussion for possible meaning for title text.</p>
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<div>I slightly disagree with the run-through of the "hopes to see it tested on mythbusters, and then scaled up to astronomical proportions" bit. Perhaps refine the first part by ending with something like "...in order to give them enough myths to be worth filming another series". The latter (a reference to the title-text, I assume) should then be dealt with in a separate para by explaining that Mythbusters ''tests'' myths experimentally, but that even the basic "use an LHC to get black holes" idea isn't going to be practically replicatable by them, let alone being able to replicate the possibility (or impossibility) of said black holes consuming the Earth. Unless TV budgets and resources are somewhat more capable than I imagine they are... [[Special:Contributions/178.107.63.150|178.107.63.150]] 21:41, 5 June 2013 (UTC)<br />
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I think the title text is also referring to the second half of the Mythbusters’ “replicate the circumstances, then duplicate the results” method. Basically, the Mythbusters would see what it ''would'' take to destroy the world (and, in the process, actually do so). Maybe they could get help from [http://qntm.org/destroy Sam Hughes] [[Special:Contributions/199.27.128.87|199.27.128.87]] 08:14, 20 July 2014 (UTC)</div>199.27.128.87https://www.explainxkcd.com/wiki/index.php?title=Talk:1252:_Increased_Risk&diff=67216Talk:1252: Increased Risk2014-05-13T10:27:33Z<p>199.27.128.87: </p>
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<div>I think this is to address the old chestnut of "<something> will ''double'' your risk of getting cancer!", or the like, where the risk of getting that cancer (in this example) is maybe 1 in 10,000, so doubling the risk across a population wouldmake that a 1 in 5,000 risk to your health... which you may still consider to be an acceptable gamble if it's something nice (like cheese!) that's apaprently to blame and you'd find abstinence from it gives a barely marginal benefit for a far greater loss of life enjoyment. Also, this sort of figure almost always applies towards a ''specific form'' of cancer, or whatever risk is being discussed, meaning you aren't vastly changing your life expectancy at all. In fact, the likes of opposing "red wine is good/bad for you" studies can be mutually true by this same principle (gain a little risk of one condition, lose a little risk from another). (Note: I don't know of any particular "cheese gives you cancer!" stories doing the rounds, at the moment. I bet they have done, but I only mention it because I actually quite like cheese. And I probably ''wouldn't'' give it up under the above conditions.)<br />
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It's also possible that this covers the likes of "<foo> in <country> is 10 times more dangerous than it is <other country>" statements. Perhaps ''only'' ten incidents happened in the former, and a single instance in the latter, out the ''whole'' of each respective country. Or a single incident occured in both, but the second country is ten times the size, so gets 'adjusted for population' in the tables. And, besides which, that was just for one year and was just a statistical blip that will probably revert-towards-the-mean next year.<br />
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Finally, for a given risk of some incident happening on the first two trips, with no 'memory' or build-up involved, it pretty much is half-as-likely-again for the incident to have happened (some time!) in three separate trips. (Not quite, if those that lose against the odds and get caught by the incident the first or second trip never get to ''have'' a (second or) third trip... but for negligable odds like thegiven example, of the dog with the handgun, it's near-as-damnit so.) [[Special:Contributions/178.104.103.140|178.104.103.140]] 11:12, 16 August 2013 (UTC)<br />
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Where did "dogs with shotguns" come from? I only saw "handgun" in the comic. Besides, I interpreted the risk as being hit by a negligent discharge from the handgun, not being deliberately attacked by the dog. Also, since probabilities are the set of real numbers between 0 and 1 inclusive, there are an uncountable number of them. "A x% increase in a tiny risk is still tiny" is an inductive statement, which means it could only be used to argue that a countable set of numbers is tiny. [[Special:Contributions/76.64.65.200|76.64.65.200]] 12:24, 16 August 2013 (UTC)<br />
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:If induction base is uncountable, you can prove it for the whole [0; 1]. For example your induction base may be "every risk under 0.00000000000000000001% is tiny". --[[User:DiEvAl|DiEvAl]] ([[User talk:DiEvAl|talk]]) 12:38, 16 August 2013 (UTC)<br />
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::Aha you caught me. I also realized that if a number is tiny, any number smaller than it is also tiny. So if we can prove that 1 is tiny, then we can prove that all numbers between 0 and 1 (known as probabilities) are tiny. [[User:Diszy|Diszy]] ([[User talk:Diszy|talk]]) 15:46, 18 August 2013 (UTC)<br />
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I think it's worth mentioning that this comic doesn't [[985|distinguish between percentages and percentage points]]. --[[User:DiEvAl|DiEvAl]] ([[User talk:DiEvAl|talk]]) 12:35, 16 August 2013 (UTC)<br />
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Is it the case that doing something three times increases risk by 50% over two times inherently? I feel like this is the case, but it's early, here. Also, I'm not sure Randall is attacked by a dog, he may be using it as a diversion. I think that he's done this before. [[User:Theo|Theo]] ([[User talk:Theo|talk]]) 12:56, 16 August 2013 (UTC)<br />
:(First, good point, DiEvAl, about the percentages/percentage-points. I ''knew'' I'd missed something out in my first thoughts. I actually tend to assume ''against'' percentage points, which is somewhat the opposite from what I've seen in the general public.)<br />
:Actually, depends on how you count it. But I was using the "encounter 'n' incidents per trip", "encounter '2n' incidents per two trips", "encoutner '3n' incidents per three trips" measure, where 3n==2n+50%. But that works best with a baseline of >>1 incidents per trip assumed. In reality, if the chance is a fractional 'p' for an occurance in one instance, it's (1-p) that it ''didn't'' occur thus (1-p)<sup>n</sup> that it didn't occur in any of 'n' instances and 1-(1-p)<sup>n</sup> that it did (at least once, possible several times or even all). Not so simple, but for p tending to zero it 'does' converge on 1.5 times for across three what you'd expect for two (albeit because 0*1.5=0). Like they say, "Lies, Damn Lies...", etc. ;) [[Special:Contributions/178.104.103.140|178.104.103.140]] 14:22, 16 August 2013 (UTC)<br />
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I don't think Randall is being attacked by a dog at all. What he's saying is that if you are going to think getting attacked by a shark is so likely, then you better be watching out for that never-gonna-happen dog scenario too. [[User:Jillysky|Jillysky]] ([[User talk:Jillysky|talk]]) 13:56, 16 August 2013 (UTC)<br />
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Is 0.000001% really "one in a million"?<br />
;If 1% = 1 in 100, then<br />
:0.1% = 1 in a 1,000<br />
:0.01% = 1 in a 10,000<br />
:0.001% = 1 in a 100,000<br />
:0.0001% = 1 in a 1,000,000<br />
:0.00001% = 1 in a 10,000,000<br />
:'''0.000001% = 1 in a 100,000,000'''<br />
Would it be more accurate to leave off the % sign?<br />
Assuming I'm right, I think it'd be less confusing to leave it and reduce the numbers by a couple orders of magnitude.<br />
--Clayton [[Special:Contributions/12.202.74.87|12.202.74.87]] 14:36, 16 August 2013 (UTC)<br />
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''If the chance of the dog attack is 0.000000001% (one in a billion) on each visit to the beach, then the chance of attack over two visits is 0.000000002% whereas in three visits it becomes 0.000000003%''<br />
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Um, no. Following that logic, if I go to the beach a billion times then I '''will''' get shot by a dog that is packing. Rather, each visit to the beach has it's own odds, like the rolling of dice? On any particular visit there's a one-in-a-billion chance. And that's true on each subsequent visit as well. Tuesday's visit to the beach isn't twice as dangerous just because I was at the beach on Monday. [[User:CFoxx|CFoxx]] ([[User talk:CFoxx|talk]]) 16:26, 16 August 2013 (UTC)<br />
:For each visit that is the case. Because it's one visit, that's true. However, if (time not being a factor) one were to have a billion visits planned, the odds over all would be increased. Pretty sure that overall this means that you got the joke faster than I did. Thanks for the clarification! [[User:Theo|Theo]] ([[User talk:Theo|talk]]) 17:06, 16 August 2013 (UTC)<br />
::The odds overall may increase with multiple visits. But not, at least, at the rate listed. Otherwise that billionth trip (if one survived that long as one is likely to do) would be certain death. [[User:CFoxx|CFoxx]] ([[User talk:CFoxx|talk]]) 17:30, 16 August 2013 (UTC)<br />
:::Correct. Technically, the odds we are worried about are the "probability of being shot one or more times by a dog". So if the probability is 1/10^9 for any given day, than the odds of not being shot are (10^9-1)/10^9 for any given day, and the odds of not being shot over three days are (10^9-1)^3/10^27, and then the odds of being shot one or more times are 1-((10^9-1)^3/10^27), which is roughly 2.999999997000000001/10^9. That is close, but slightly less, than 3/10^9. [[Special:Contributions/206.174.12.203|206.174.12.203]] 18:01, 16 August 2013 (UTC)Toby Ovod-Everett<br />
::::Absolute incorrect: You always have to look at the single event. More events do not belong together, you always have the same probability at each single event. So, even 10 billion events may or may NOT result in a disaster. Math isn't easy.--[[User:Dgbrt|Dgbrt]] ([[User talk:Dgbrt|talk]]) 19:17, 16 August 2013 (UTC)<br />
:::::I believe what CFoxx was saying is that if the odds of something happening on any given day are one in three, then the odds of that thing happening at least once during a four day period is NOT 4/3rds! I was pointing out that the proper way to calculate the odds for a four day period is to say that the odds of it not happening on any given day are two in three. You take that probability and raise it to the fourth power, giving the odds that it won't happen at all during a four day period of 16/81, thus the odds that it will happen during that four day period is 65/81. I then did that same calculation for the 1 in a billion chance per day and applied it to the three day period, and recognized that he was correct that the true probability of the event happening one or more times over a three day period was not three times the probability of it happening on any given day, but also noted that the difference for a 1 in a billion chance over a small period is pretty close to the simplistic (but incorrect) approach. My rough estimate for the "one in a billion per day" event happening one or more times during a billion day period is 63.21%.[[Special:Contributions/206.174.12.203|206.174.12.203]] 21:33, 16 August 2013 (UTC)Toby Ovod-Everett<br />
::::::Wow, we still have many great scientists here!--[[User:Dgbrt|Dgbrt]] ([[User talk:Dgbrt|talk]]) 21:46, 16 August 2013 (UTC)<br />
::::::THANK YOU, Toby! [[User:CFoxx|CFoxx]] ([[User talk:CFoxx|talk]]) 18:09, 17 August 2013 (UTC)<br />
<br />
Just a thought: is the title text a reference to the Sorites paradox? --AJ [[Special:Contributions/80.42.221.105|80.42.221.105]] 17:25, 16 August 2013 (UTC)<br />
<br />
Rats! I made the newbie mistake of editing something before I found the discussion page. I looked for it, honest I did! I see that UTC has already brought up what I referred to as "Cueball's error" in my (pre-log-in) edit. I did find it hard to believe I'd be the first xkcd fan to notice this error. I think this is worth addressing in the explanation, though I of course won't take offense if someone wants to obliterate my edit and start over. (CLSI){{unsigned|CLSI}}<br />
<br />
Maybe he means this: Florida man shot by his dog, police say http://usnews.nbcnews.com/_news/2013/02/26/17107343-florida-man-shot-by-his-dog-police-say?lite{{unsigned|Jb}}<br />
<br />
Saying that unfortunately Cueball is mistaken in his calculations because he said 50% instead of 49.99999992% is a bit of an exaggeration. [[User:Xhfz|Xhfz]] ([[User talk:Xhfz|talk]]) 20:19, 16 August 2013 (UTC)<br />
<br />
In regards to the "flipping a coin and having it come up with heads 9 times in a row being no indication of future results" thing, I have to throw out that ''that'' is a common misunderstanding in basic logic; it's an example that people throw out all the time without really considering the real-life implications. With a truly fair coin, the situation as described is certainly true. But the odds of a fair coin coming up heads 9 times in a row is 512-to-1 against. That coin is overwhelmingly likely not a fair coin. I would say the odds of that coin flipping heads on the 10th flip is pretty damn close to unity. [[User:Hoopy Frood|Hoopy Frood]] ([[User talk:Hoopy Frood|talk]]) 17:00, 25 August 2013 (UTC)<br />
<br />
;Chaos at explain section<br />
Please stop adding this, it does not explain the comic, it only belongs to this discussion page:<br />
<br />
:Note that the 50% figure is an approximation. Assuming the odds of being attacked by a dog is ''x'', the odds of being attacked by a dog at least once in two visits is 1 - (1-''x'')<sup>2</sup>. The odds of being attacked at least once in three visits is 1 - (1-''x'')<sup>3</sup>. Therefore, if one visit has one in a billion probability of attack, then two visits have not 2 in a billion, but 1.999999999 in a billion. Similarly, three visits have a probability of 2.999999997 in a billion. Saying 50% instead of 49.99999992% is a reasonable approximation. <br />
<br />
:Unfortunately, [[Cueball]] is mistaken in his calculations. This is easier to see with an event that has greater probability, such as a coin toss. Assuming the odds of getting heads in one flip is .5, the odds of getting heads at least once in two flips is .75 (i.e., 1 minus [.5 X .5], the odds of getting tails both times), and the odds of getting heads at least once in three flips is .875 (1 minus [.5 X .5 X .5], the odds of getting three tails in a row). Getting heads in three flips is not 50% more likely than getting heads in two flips. With very low probabilities (such as the probability of attack by a dog swimming with a handgun), Cueball's calculation gives an extremely close approximation of the actual probability, but one can't apply the same logic to events of just any probability.<br />
<br />
::Cueball says *statistically* the risk of some bizarre event increases 50%. This is essentially correct as many have pointed out that 49.99999999 is not really statistically different than 50. What is likely bothering a lot of people (including myself) is that the explainxkcd description states "If the chance of the dog attack is one per billion on each visit to the beach, then the chance of attack over two visits *is* two per billion whereas in three visits it *becomes* three per billion." There are no weasel words like "approximately", "about", "around", etc. This reminds people of flatly incorrect uses of probabilities like the one you describe. But surely the probability of getting heads from a fair coin toss is not on a similar order of magnitude as the probability that a swimming dog shoots someone with a handgun. [[User:S|S]] ([[User talk:S|talk]]) 00:40, 17 August 2013 (UTC)<br />
:::''What is likely bothering a lot of people (including myself) is that the explainxkcd description states "If the chance of the dog attack is one per billion on each visit to the beach, then the chance of attack over two visits *is* two per billion whereas in three visits it *becomes* three per billion." There are no weasel words like "approximately", "about", "around", etc.'' '''Exactly.''' Explanations here have been very helpful in explaining some of the more scientific aspects of things Randall includes. Noting this one makes a (albeit slight) mistake in that regard is appropriate. (And the irony of incorrectly using probabilities in explaining a comic about how people do that is amusing.) [[User:CFoxx|CFoxx]] ([[User talk:CFoxx|talk]]) 18:15, 17 August 2013 (UTC)<br />
<br />
I had to think of http://xkcd.com/1102/ when reading the first paragraph of the explainxkcd description. (The context is different, but the dubious use of percentages is the same.) [[User:S|S]] ([[User talk:S|talk]]) 00:40, 17 August 2013 (UTC)<br />
<br />
;Proof<br />
I believe Cuball's calculation is way off. The odds of a dog attack should increase by 50% when looking at two beach trips rather than one. But the odds of an attack occurring with 3 visits should only increase by about 16.67%. This can be seen by analyzing a fair dice roll or a coin toss. Unless I am missing something, even with extremely small probabilities, this will hold. Can anyone write a proof to show otherwise?{{unsigned ip|174.98.234.239}}<br />
:As far as I understand it: doing something twice doubles your chance of getting the desired outcome. For example, you want to role a dice and get a six. If you role it twice, you have double the chance of getting at least one six. If you role it three times you have triple the chance of getting a six; in other words you increase it from two chances to three chances, which is an increase of 50%. {{unsigned ip|213.86.4.78}}<br />
::It doubles the likely number of sixes, but does not double the chance of getting at least one six. This is because there is a small chance of getting two sixes, and while that counts as two sixes for the number of occurrences, it still only counts as one chance of getting at least one six. The easiest way to visualize this is to look at the probability that you won't get a six in any given roll of the die, which is 5/6ths. Each time you roll, the probability you won't get a six at all goes down by 5/6ths. So the probability for two rolls is 25/36ths, and thus the probability of getting one or more sixes in two rolls is 11/36ths. This is 1/36th less than 2/6ths, and 1/36th is the probability of getting two sixes. Similar (although more complicated) logic applies to rolling it three times, for which the probability of getting at least one 6 is 91/216ths (not 108/216ths, as the naive approach would imply). As others (CFoxx) have pointed out, if you roll a die 6 times, there is still a chance you won't get any sixes. If you roll it a million times, it is still possible (albeit very, very, very unlikely) that you wouldn't get any sixes! As far as the 50% and 16.67% figures given by the original poster, I believe those were calculated for events that have a 50% probability for each event. The increase in probability from 1 to 2 events where 1/x is the probability looks like (1-(1-1/x)^2)/(1/x)-1, which is (1-(1-2/x+1/x^2))*x-1 or (2/x-1/x^2)*x-1 or (2-1/x)-1 or 1-1/x. Thus for an event like a fair coin toss, the increase in probability for two tosses over one toss is 1/2. For a 6-sided die, the increase in probability is 5/6th. For a 1/billion, the increased probability for one or more occurrence for two events compared with one event is 0.999999999. Finally, the probability of the second event being the desired event is always the same. It is unchanged by the first event. It is the probability of either (or both) of the events being desired that we are calculating here. If the first die roll is a six, the probability of the second being a six is still 1/6. If the first die roll is not a six, the probability of the second being a six is still 1/6 (assuming a fair die). But the probability of either or both being a six is the absence of any information about the two rolls is not 2/6, but rather 11/36! [[Special:Contributions/206.174.12.203|206.174.12.203]] 17:06, 21 August 2013 (UTC)Toby Ovod-Everett<br />
<br />
I shared this comic with risk-assessor friends in Massachusetts and got the following responses:<br />
"Tee-hee. If you change the beach to Chatham, however, it's just not as funny!" (Cape Cod beaches have new signs warning of great white shark attacks: http://www.bostonglobe.com/magazine/2013/08/17/chatham-bold-attempt-become-new-england-great-white-shark-capital/TtfcEZsAo6PN7lUoBKe1kO/story.html)<br />
"Or in our line of work, we worry (in MA) if the risk of cancer is 0.00002 but not if it is 0.00001 or less, which, as the base rate of cancer is around 40%, means that we're worried about a cancer incidence rate of 0.40002 but not 0.40001. And one could almost argue that it'd be pretty hard to distinguish these two, and even that if we presented risks in this form to the general public, they might wonder why we're so concerned..."<br />
"Makes you wonder what the risk was for that Marlin coming on board that boat in Florida - http://www.wfla.com/story/23239959/350-pound-marlin-jumps-in-boat-landing-on-crew?"<br />
I guess it all depends on your point of view. One might argue that the "gambler's fallacy" is the primary driver of lottery income, which, according to the North American Association of State and Provincial Lotteries: "During fiscal year 2012 (which for most jurisdictions ended June 30) U.S. lottery sales totaled $78 billion ($US). Canadian sales reached $9.3 billion ($Can)." (http://www.naspl.org/index.cfm?fuseaction=content&menuid=14&pageid=1020). Is "Remember to Play all Lottery Games Responsibly" an oxymoron?{{unsigned|Hoopy}}<br />
<br />
I am troubled with this paragraph: "This also can be illustrated by coin flips: if one flips a coin 10 times in a row, no matter what the result of each previous flip is (even if it were nine heads in a row), the odds of getting heads on the next coin flip remains 50%. In other words, past experience does not impact subsequent flips."<br />
<br />
This paragraph does not specify the use of a fair coin. If 9 flips all come up heads, then there is strong statistical evidence that the probability of getting a head in a flip is not 50% (P=1/2^9=1/512~0.2%). It is still true that "past experience does not impact subsequent flips", but in this case, our judgment about the true probability should change in light of new data. [[Special:Contributions/199.27.128.87|199.27.128.87]] 10:27, 13 May 2014 (UTC)</div>199.27.128.87https://www.explainxkcd.com/wiki/index.php?title=1351:_Metamaterials&diff=644091351: Metamaterials2014-04-04T21:53:04Z<p>199.27.128.87: </p>
<hr />
<div>{{comic<br />
| number = 1351<br />
| date = April 4, 2014<br />
| title = Metamaterials<br />
| image = metamaterials.png<br />
| titletext = If I developed a hue-shifting metamaterial, I would photobomb people's Instagram pics with a sheet of material that precisely undid the filter they were using.<br />
}}<br />
<br />
==Explanation==<br />
<br />
{{w|Metamaterials}}, artificially created materials typically composed of very finely structured “conventional” materials, may cause light passing through them to shift. The exact color it shifts to varies based on the design of the material. (At least that seems to be the underlying assumption of the comic. Real metamaterials, however, are spectrally linear systems. They have a spatially modulated structure, hence they can do weird stuff with light ''spatially''. Color is a function of frequency/time though.)<br />
<br />
In today’s comic, Megan uses her metamaterial (which is in the shape of a box) to switch the colors of the cliché Valentine’s Day poem, “{{w|Roses are red}}, violets are blue, sugar is sweet and so are you.”<br />
<br />
The title text references this with Randall pondering making a metamaterial that reverses the effect of {{w|instagram}} filters, likely by placing the material between the camera and the subject just before the picture is taken. Instagram is a photo application that applies one of a variety of filters (usually hue shift/contrast adjustments) meant to simulate the look of old photographs.<br />
<br />
==Transcript==<br />
<br />
:[Picture of a red violet.]<br />
:Megan (off-screen): Violets are red.<br />
<br />
:[Picture of a blue rose.]<br />
:Megan (off-screen): And roses are blue.<br />
<br />
:[Megan holding sheet of transparent material in front of the two flowers: red violet, blue rose. Cueball stands nearby.]<br />
:Megan: When metamaterials<br />
<br />
:[Megan moves the object away from the flowers. Now violet is blue, and rose is red]<br />
:Megan: Alter their hue.<br />
<br />
{{comic discussion}}<br />
[[Category:Comics featuring Cueball]]<br />
[[Category:Comics featuring Megan]]<br />
[[Category:Comics with color]]</div>199.27.128.87https://www.explainxkcd.com/wiki/index.php?title=User:199.27.128.87&diff=59476User:199.27.128.872014-02-05T22:18:32Z<p>199.27.128.87: Created page with "IP address for a Charter internet subscription in Laramie, WY."</p>
<hr />
<div>IP address for a Charter internet subscription in Laramie, WY.</div>199.27.128.87https://www.explainxkcd.com/wiki/index.php?title=61:_Stacey%27s_Dad&diff=5947561: Stacey's Dad2014-02-05T22:17:24Z<p>199.27.128.87: /* Explanation - small addition */</p>
<hr />
<div>{{comic<br />
| number = 61<br />
| date = February 8, 2006<br />
| title = Stacey's Dad<br />
| image = staceys_dad.jpg<br />
| titletext = I bet she gets you to mow the lawn, doesn't she?<br />
}}<br />
<br />
==Explanation==<br />
This comic refers to the song "{{w|Stacy's Mom}}", by {{w|Fountains of Wayne}}. As the background singers repeatedly say, "Stacy's mom has got it goin' on." <br />
<br />
Here are the lyrics for the second verse:<br />
:<i>Stacy, do you remember when I mowed your lawn? (mowed your lawn)<br />
:Your mom came out with just a towel on (towel on)<br />
:I could tell she liked me from the way she stared (the way she stared)<br />
:And the way she said, "You missed a spot over there" (a spot over there)<br />
:And I know that you think it's just a fantasy<br />
:But since your dad walked out, your mom could use a guy like me</i><br />
<br />
(chorus)<br />
:<i>Stacy's mom has got it goin' on<br />
:She's all I want, and I've waited so long<br />
:Stacy, can't you see you're just not the girl for me<br />
:I know it might be wrong,<br />
:but I'm in love with Stacy's mom</i><br />
<br />
The humor in this is that in the song the singer finds Stacy's Mom desirable, but in the comic the dad, who walked out, is saying that she is very undesirable and the singer should run away while he still can. "That woman has a lot going on" alludes directly to the first line of the chorus, but refers to the things that are going on in a negative, rather than a positive, light.<br />
<br />
The title text elaborates on this idea, implying that she manipulated the singer to mow her lawn through rewarding the singer by making an appearance with "just a towel on."<br />
<br />
==Transcript==<br />
:Stacey's Dad: Look, I know you think that since I walked out she could use a guy like you. But trust me. That woman has got a lot going on, and you want none of it. Get out while you still can.<br />
<br />
:[Printed across the bottom of the panel.]<br />
:Stacey's dad.<br />
<br />
{{comic discussion}}<br />
[[Category:Music]]</div>199.27.128.87https://www.explainxkcd.com/wiki/index.php?title=1313:_Regex_Golf&diff=567071313: Regex Golf2014-01-06T06:13:59Z<p>199.27.128.87: /* Explanation */ Provided initial explanation</p>
<hr />
<div>{{comic<br />
| number = 1313<br />
| date = January 6, 2014<br />
| title = Regex Golf<br />
| image = regex_golf.png<br />
| titletext = <nowiki>/bu|[rn]t|[coy]e|[mtg]a|j|iso|n[hl]|[ae]d|lev|sh|[lnd]i|[po]o|ls/ matches the last names of elected US presidents but not their opponents.</nowiki><br />
}}<br />
<br />
==Explanation==<br />
<br />
This comic revolves around a set of increasingly complicated [http://en.wikipedia.org/wiki/Regular_expression regular expressions], which are patterns used to search through text for blocks of text matching the pattern. There is a saying in professional programming that goes like this: <br />
Some people, when confronted with a problem, think “I know, I'll use regular expressions.” Now they have two problems.<br />
The comic exemplifies this as Megan's problems grow increasingly convoluted - originally she was writing regex as a game, then moved on to automatically building regex on arbitrary lists of text, to searching through her files for code that appears to be a regex golf generator. At the end, Cueball quips that she now has "Infinite Problems" as a result of her efforts, tying back to the saying above.<br />
<br />
==Transcript==<br />
:Regex golf:<br />
:[Megan is sitting at a laptop. Cueball is standing behind her.]<br />
:Megan: You try to match one group but not the other.<br />
:Megan: /m | [tn]|b/ matches ''Star Wars'' subtitles but not ''Star Trek''.<br />
:Cueball: Cool.<br />
<br />
:Meta-regex golf:<br />
:Megan: So I wrote a program that plays regex golf with arbitrary lists...<br />
:Cueball: Uh oh...<br />
<br />
:Meta-meta-regex golf:<br />
:Megan: ...But I lost my code, so I'm grepping for files that look like regex golf solvers.<br />
<br />
:...And beyond:<br />
:Megan: Really, this is all /(meta-)*regex golf/.<br />
:Cueball: Now you have ''infinite'' problems.<br />
:Megan: No, I had those already.<br />
<br />
{{comic discussion}}<br />
[[Category:Comics featuring Cueball]]<br />
[[Category:Comics featuring Megan]]<br />
[[Category:Computers]]</div>199.27.128.87