explain xkcd - User contributions [en]

Talk:2313: Wrong Times Table

2020-06-01T19:12:36Z

162.158.158.201:

Such an illogical table. Smaller numbers multiply to larger answers than larger numbers? Even numbers multiply to odd numbers?! How?!?! What sort of illiterate alien declared this to be the multiplication table?! [[Special:Contributions/108.162.221.101|108.162.221.101]] 20:54, 29 May 2020 (UTC)

This is easily one of the worst XKCD comics, period. Not funny, nor clever. Just seems like noise. [[Special:Contributions/172.69.68.183|172.69.68.183]] 20:57, 29 May 2020 (UTC)
:I suspect Randall may have just been feeling random, perhaps after several months of mostly Coronavirus-related comics. [[User:Barmar|Barmar]] ([[User talk:Barmar|talk]]) 21:13, 29 May 2020 (UTC)
::That's fair, I'm being a bit harsh, but this just comes across as exceptionally meaningless and contrived, so much so that I felt the need to come here and comment immediately for the first time ever [[Special:Contributions/172.69.71.56|172.69.71.56]] 21:18, 29 May 2020 (UTC)
:I relate to certain mathematical facts not sounding right, like how 54 intuitively feels like it's divisible by 4. Nonsensical, but makes sense anyway. [[Special:Contributions/162.158.62.233|162.158.62.233]] 21:42, 29 May 2020 (UTC)

This seems like the multiplication equivalent of looking at a word and thinking it is spelled incorrectly. Sometimes I look at a simple word like "fish" and think: "That can't be right." Sometimes multiplication can feel that way, particularly 7's because those were tricky for some reason. The alt text confirms fishiness with 7's [[Special:Contributions/108.162.246.173|108.162.246.173]] 21:09, 29 May 2020 (UTC)
:Is it weird that I ''don't'' get this? I have this sense of "that is obviously wrong" when it comes to multiplication of small numbers like these, even with sevens and eights. If I read that 7 * 8 = 54, my brain screams "NOOOOOOOOO IT IS 56 YOU IDIOT!". [[Special:Contributions/108.162.221.101|108.162.221.101]] 21:14, 29 May 2020 (UTC)
::It's lucky for you! Careless errors [of all types] can be annoying, and sometimes difficult to locate... Some of us have ingrained this information better than others. (This comic seems less like a joke and more sharing a hindrance Randall suffers from when doing arithmetic. And speaking personally, I can certainly relate to that.)[[Special:Contributions/162.158.78.50|162.158.78.50]] 18:05, 1 June 2020 (UTC)

Well, 2,2 that's actually 2^3=8. 2,3 is addition instead of multiplication. 1,2 is division instead of multiplication. 1,1 is subtraction. 10,10 seems to be a visual gag, though most of the 10s row is either multiplication by 11 or 12... There's some logic to some of these, but it's different for each row, column, or cell. [[Special:Contributions/162.158.74.167|162.158.74.167]] 21:13, 29 May 2020 (UTC)
:Yeah, there is something going on. It looks like a lot of it is remembering the correct answer to a different problem. By my count 55 squares are the correct answer to a square next to it and 31 have a correct answer for somewhere else on the grid. Also, 2*2, 4*4 and 5*5 are double the correct answer.[[Special:Contributions/108.162.245.76|108.162.245.76]] 21:41, 29 May 2020 (UTC)

It's almost disappointing that he didn't hide one or two asymmetries in there just to throw us off! [[Special:Contributions/108.162.216.114|108.162.216.114]] 22:04, 29 May 2020 (UTC)

I get the idea that this is the sort of table you'd get if you tried to train an Adversarial AI from scratch to determine x*y purely by stocastic guessing and comparing to a co-evolving 'scorer' that also starts off naively but supports each answer according to the 'rightness' it thinks it has ''except'' for the real answer which is always hard-coded to be down-scored. (Also noting that DA reportedly came by his choice of 42 by asking people which numbers were 'funnier' than others, which can be said to be a similar kind of process but without the arrayed "original multiplication" element.) [[Special:Contributions/162.158.158.179|162.158.158.179]] 22:13, 29 May 2020 (UTC)

As someone who often confuses 7*8 as 54, I found the alt text very humorous. [[Special:Contributions/172.69.34.118|172.69.34.118]] 22:29, 29 May 2020 (UTC)

I'm disappointed to see that 6*9 isn't equal to 42. [[User:Probably not Douglas Hofstadter|Probably not Douglas Hofstadter]] ([[User talk:Probably not Douglas Hofstadter|talk]]) 23:01, 29 May 2020 (UTC)

This is just a collection of equations with the wrong answers. I'm not sure who finds this funny. [[Special:Contributions/108.162.219.96|108.162.219.96]] 00:33, 30 May 2020 (UTC)

https://www.explainxkcd.com/wiki/index.php/1210:_I%27m_So_Random[[User:Overlord of oddities|Overlord of oddities]] ([[User talk:Overlord of oddities|talk]]) 01:16, 30 May 2020 (UTC)

I have asked [https://codegolf.stackexchange.com/q/205425/67157 a Code Golf Stack Exchange question] with the goal of producing the shortest program that computes this function. [[User:Aaron Rotenberg|Aaron Rotenberg]] ([[User talk:Aaron Rotenberg|talk]]) 02:29, 30 May 2020 (UTC) @Aaron I had a similar thought, but was going to settle for the generator function for the main diagonal. If we can come up with one, we should submit it to https://oeis.org/ [[User:Cellocgw|Cellocgw]] ([[User talk:Cellocgw|talk]]) 13:30, 1 June 2020 (UTC)

I'm disappointed that 17 does not show up in any product cell, seeing as I've known since at least 1970 that 17 is the world's most random number. <-- a fact proved for a limited case here: https://www.youtube.com/watch?v=2JPSJL7Kvus [[User:Cellocgw|Cellocgw]] ([[User talk:Cellocgw|talk]]) 13:35, 1 June 2020 (UTC)

I too was unimpressed with this... unitl I got to the alt text. I'm in my sixties now, and for some reason, 8*7 has ALWAYS been difficult for me. I find myself always doube-checking to make sure I did it right. And 6*7 gave me problems too, but I got over that a few decades ago. I wonder what it is about those that gave us trouble. --[[Special:Contributions/162.158.62.75|162.158.62.75]] 14:35, 1 June 2020 (UTC)

I do not believe that the table was constructed rationally, but intuitively by Randall. He took the two factors (in both permutations) and thought, which resulting number he felt best about. It is more like a psychological experiment than a table constructed with a system or code in mind. Sebastian --[[Special:Contributions/162.158.89.193|162.158.89.193]] 16:27, 1 June 2020 (UTC)

Am I the only one who reads the author's intention slightly differently? I don't think that he intended that these values feel more correct than the real multiplication table. Rather, I thought he meant that from all possible ''wrong'' values, these feel ''most'' correct to him. In this way, I at least could sympathise with many values given here. [[Special:Contributions/162.158.238.216|162.158.238.216]] 17:34, 1 June 2020 (UTC)
:Agreed--he doesn't feel that the answers are incorrect, but rather, if he were given the problem on a test, "True or False: One times two equals one half.", he'd have to think for a minute. [[Special:Contributions/162.158.78.50|162.158.78.50]] 18:08, 1 June 2020 (UTC)
::I just edited that (first) bit, myself, before seeing your comments. I hope this version is better for you (might need further editing later in the paragraph, but stil considering this). [[Special:Contributions/162.158.158.201|162.158.158.201]] 19:12, 1 June 2020 (UTC)

2313: Wrong Times Table

2020-06-01T19:08:05Z

162.158.158.201: /* Explanation */ Only for two products does he actually say the correct answers look wrong, in all other respects these are wrong answers that apparently seem more correct than any alternate wrong answer.

{{comic
| number = 2313
| date = May 29, 2020
| title = Wrong Times Table
| image = wrong_times_table.png
| titletext = Deep in some corner of my heart, I suspect that real times tables are wrong about 6x7=42 and 8x7=56.
}}

==Explanation==
{{incomplete|Created by 6x7. Please mention here why this explanation isn't complete. Do NOT delete this tag too soon.}}
A "times table" (or {{w|multiplication table}}) is a table used to define multiplication between numbers. Typically, elementary school children are taught to memorize the table as part of learning arithmetic.

In this comic, [[Randall]] supplies his own alternate version of the times table, with entirely incorrect values that nonetheless "feel" reasonably correct to him. It is unclear how his values are derived, as they don't follow a consistent pattern, but it could be that when calculating products, he sometimes has to correct his mental arithmetic, perhaps thinking along such lines as "8*4 is 36... Or, wait, is it 32?". Most of the values are transposed from their correct position (i.e. adding or subtracting one -- or two, or three -- from one or both multiplicands), some are "off by one" (or two, or by a factor of two), and some (mostly in the 1 row and column) could be created by adding, subtracting, or dividing the two factors instead of multiplying them. It is notable that some properties of mathematics are not followed, as sometimes smaller multiplicands multiply to a larger product than larger multiplicands, and sometimes two even multiplicands produce an odd product.

The times table is symmetric, indicating that Randall's form of multiplication is [[wikipedia:Commutative property|commutative]].

The title text (referencing Randall's suspicion that 6x7=42 may be wrong) may be an allusion to ''{{w|The Hitchhiker's Guide to the Galaxy}}'', in which the ultimate answer to life, the universe, and everything is said to be {{w|Phrases_from_The_Hitchhiker%27s_Guide_to_the_Galaxy#The Answer to the Ultimate Question of Life, the Universe, and Everything is 42|forty-two}}. However, this answer is meaningless without knowing the ultimate ''question'', and so a planet-sized computer is constructed to calculate the ultimate question, which later becomes Earth, but Earth is destroyed shortly before its calculation is complete. Arthur Dent, one of the last surviving humans, attempts to recreate the ultimate question (hoping it may be stored within himself somehow, as a remnant of Earth) by picking letter tiles from a bag, and produces the sentence "What do you get if you multiply six by nine". This leads him to remark "I always thought something was fundamentally wrong with the universe." (6x9 = 42 in base thirteen, but when asked about this, Douglas Adams replied, "I may be a sorry case, but I don't write jokes in base 13.") In this table, neither 6x7 nor 6x9 are said to result in 42, but 7x7. Note however that operation of said planet-sized computer was disrupted so it's also possible the universe is ok and just the question was computed incorrectly.

If we consider the smaller multiplicand to be ''a'' and the larger to be ''b'', then (one of infinitely many possibilities of) the formulas used by Randall are as follows:

{| class="wikitable" style="text-align: center;"
!
! scope="column" | 1 || 2 || 3 || 4 || 5 || 6 || 7 || 8 || 9 || 10
|-
! scope="row" | 1
| a-b || a/b || a+b ||a+b || a+b || a+b || a+b || a+b || a+b || a (b-1)
|-
! scope="row" | 2
| a/b || 2ab || a+b || a(b-1) || a(b+1) || a(b+1) || a(b-1) || b+10 || b+10 || a(b+1)
|-
! scope="row" | 3
| a+b || a+b || ab+1 || (a+1)b || a(b-1)+1 || (a-1)b || a(b+1) || (a+1)b || a(b-2) || a(b+1)
|-
! scope="row" | 4
| a+b || a(b-1) || (a+1)b || 2ab || (a+1)b || (a+1)(b-1) || ab+1 || a(b+1) || a(b-2) || a(b+2)
|-
! scope="row" | 5
| a+b || a(b+1) || a(b-1)+1 || (a+1)b || 2ab || (a-1)b || a(b+1) || a(b+1) || a(b-1) || (a+1)b
|-
! scope="row" | 6
| a+b || a(b+1) || (a-1)b || (a+1)(b-1) || (a-1)b || (a-2)(b+2) || a(b+1) || ab+2 || a(b+3) || a(b+2)
|-
! scope="row" | 7
| a+b || a(b-1) || a(b+1) || ab+1 || a(b+1) || a(b+1) || a(b-1) || (a-1)(b+1) || (a-1)(b+1) || a(b+2)
|-
! scope="row" | 8
| a+b || b+10 || (a+1)b || a(b+1) || a(b+1) || ab+2 || (a-1)(b+1) || a(b-2) || ab+2 || a(b-3)
|-
! scope="row" | 9
| a+b || b+10 || a(b-2) || a(b-2) || a(b-1) || a(b+3) || (a-1)(b+1) || ab+2 || a(b-1) || a(b-1)
|-
! scope="row" | 10
| a(b-1) || a(b+1) || a(b+1) || a(b+2) || (a+1)b || a(b+2) || a(b+2) || a(b-3) || a(b-1) || a(b+1)
|}

The "correct"{{Citation needed}} times table for the numbers from 1-10 is below:
{| class="wikitable" style="text-align: center;"
! ×
! scope="column" | 1 || 2 || 3 || 4 || 5 || 6 || 7 || 8 || 9 || 10
|-
! scope="row" | 1
| 1 || 2 || 3 || 4 || 5 || 6 || 7 || 8 || 9 || 10
|-
! scope="row" | 2
| 2 || 4 || 6 || 8 || 10 || 12 || 14 || 16 || 18 || 20
|-
! scope="row" | 3
| 3 || 6 || 9 || 12 || 15 || 18 || 21 || 24 || 27 || 30
|-
! scope="row" | 4
| 4 || 8 || 12 || 16 || 20 || 24 || 28 || 32 || 36 || 40
|-
! scope="row" | 5
| 5 || 10 || 15 || 20 || 25 || 30 || 35 || 40 || 45 || 50
|-
! scope="row" | 6
| 6 || 12 || 18 || 24 || 30 || 36 || 42 || 48 || 54 || 60
|-
! scope="row" | 7
| 7 || 14 || 21 || 28 || 35 || 42 || 49 || 56 || 63 || 70
|-
! scope="row" | 8
| 8 || 16 || 24 || 32 || 40 || 48 || 56 || 64 || 72 || 80
|-
! scope="row" | 9
| 9 || 18 || 27 || 36 || 45 || 54 || 63 || 72 || 81 || 90
|-
! scope="row" | 10
| 10 || 20 || 30 || 40 || 50 || 60 || 70 || 80 || 90 || 100
|}

==Transcript==
{{incomplete transcript|Do NOT delete this tag too soon.}}
:[Caption above table:]
:<big>Wrong Times Table</big>
:The incorrect answers that feel most right to me

{| class="wikitable" style="text-align: center;"
!
! scope="column" | 1 || 2 || 3 || 4 || 5 || 6 || 7 || 8 || 9 || 10
|-
! scope="row" | 1
| 0 || ½ || 4 || 5 || 6 || 7 || 8 || 9 || 10 || 9
|-
! scope="row" | 2
| ½ || 8 || 5 || 6 || 12 || 14 || 12 || 18 || 19 || 22
|-
! scope="row" | 3
| 4 || 5 || 10 || 16 || 13 || 12 || 24 || 32 || 21 || 33
|-
! scope="row" | 4
| 5 || 6 || 16 || 32 || 25 || 25|| 29 || 36 || 28 || 48
|-
! scope="row" | 5
| 6 || 12 || 13 || 25 || 50 || 24 || 40 || 45 || 40 || 60
|-
! scope="row" | 6
| 7 || 14 || 12 || 25 || 24 || 32 || 48 || 50 || 72 || 72
|-
! scope="row" | 7
| 8 || 12 || 24 || 29 || 40 || 48 || 42 || 54 || 60 || 84
|-
! scope="row" | 8
| 9 || 18 || 32 || 36 || 45 || 50 || 54 || 48 || 74 || 56
|-
! scope="row" | 9
| 10 || 19 || 21 || 28 || 40 || 72 || 60 || 74 || 72 || 81
|-
! scope="row" | 10
| 9 || 22 || 33|| 48 || 60 || 72 || 84 || 56 || 81 || 110
|}

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

1361: Google Announcement

2020-04-27T12:05:09Z

162.158.158.201: /* Explanation */

{{comic
| number = 1361
| date = April 28, 2014
| title = Google Announcement
| image = google_announcement.png
| titletext = The less popular 8.8.4.4 is slated for discontinuation.
}}

==Explanation==
At the time of this comic's release, {{w|Vic Gundotra}} had recently left {{w|Google}}. Because he was the head of {{w|Google+}}, this had caused many people, including [http://techcrunch.com/2014/04/24/google-is-walking-dead/ TechCrunch], to theorize that Google+ was going to be shut down, despite the continuing comments from Google that it would remain active and updated. It lasted five more years, finally being closed on April 2nd, 2019.

Google has a history of closing popular services {{w|List of Google products#Discontinued products and services|listed}}.

The comic extrapolates this to an announcement that Google would be closing '''all''' its popular services, up to and including its e-mail service, Gmail, and even the core business of the company, its Internet search engine, to wholly concentrate on a relatively obscure part of its product lineup. According to Google, its Public {{w|Name server|DNS servers}} (Domain Name System servers), better known by their IPv4 addresses {{w|8.8.8.8|8.8.8.8 and 8.8.4.4}}, are supposed to be a faster alternative to using one's ISP's DNS servers (because of caching effects due to a large user base), as well as less susceptible to censorship. When Turkey started blocking access to Twitter and YouTube in March 2014, Turkish ISPs first did this on the DNS level by manipulating the results from their own name servers. The most popular workaround was using Google's DNS server instead, so much so that its address was written as [http://gawker.com/turkish-graffiti-spreads-the-ip-addresses-of-googles-d-1548946312 graffiti on the side of a building].

The joke may also be related to the fact that 8.8.8.8 is an IP address heavily used by network administrators to perform connectivity tests (''ping'') because it is easy to remember and fast to type. Google would want to concentrate on this feature to build a business model using that fact.

The reason behind this decision may be that Google considers a DNS server, a fairly low-level component of the Internet's service stack, to be the optimal place to collect information on its users, an accusation leveled at Google ever since it introduced the service.

The title text refers to the impression held by some that Google will shut down services that prove less popular than desired at short notice, even though they may in fact have a significant user base. A recent example of that is the closure of the RSS aggregation service, Google Reader, in July 2013. While the same DNS service is provided under both addresses, the more memorable 8.8.8.8 is likely to receive far more requests than 8.8.4.4.

==Transcript==
:[Cueball is standing at a lectern marked Google.]
:Cueball: The rumors are true. Google will be shutting down Plus—
:Cueball: Along with Hangouts, Photos, Voice, Docs, Drive, Maps, Gmail, Chrome, Android, and Search—
:Cueball: To focus on our core project:
:Cueball: The 8.8.8.8 DNS Server.

==Trivia==
*Google quickly responded with an acknowledgment to a query for "xkcd". The TXT record for the DNS name of the IP address 8.8.8.8 was set to "http://xkcd.com/1361/", an entry just meant to be informal.
*In October 2018 Google really announced to [https://www.blog.google/technology/safety-security/project-strobe/ shut down Google+].

{{comic discussion}}
[[Category:Comics featuring Cueball]]
[[Category:Internet]]