2215: Faculty:Student Ratio

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Faculty:Student Ratio
They managed to briefly hit the top of the rankings when they rejected everyone except one applicant, published 5 billion research papers that just said "Hi," and hired one of their graduates for $50 trillion/year (then fired them after 10 microseconds.)
Title text: They managed to briefly hit the top of the rankings when they rejected everyone except one applicant, published 5 billion research papers that just said "Hi," and hired one of their graduates for $50 trillion/year (then fired them after 10 microseconds.)


Universities are often rated in various ways to help students/parents pick which one to attend. This comic satirizes the very real culture of schools modifying their actions to artificially inflate their ratings. One metric used in ratings is the ratio between the number of faculty members to the number of students. Typically this is expressed as the student-teacher ratio, which normally determines how much time teachers get to spend with individual students. The lower the ratio, i.e., the fewer students per teacher, the smaller classes teachers have to teach, and thus the more attention the teachers can give to each student. However, having many more teachers than student(s), as in this comic, is not very beneficial to the student(s). (For context for international readers, high student-teacher ratios are common and expected in the United States, Randall's home country, whereas some nations especially in Asia sometimes report much lower ratios, often close to 1:1 in some areas.)

Another metric commonly used to measure a college's exclusivity and therefore prestige is the college's rejection rate; more prestigious schools get more applicants, and since they can accept only a limited number, they must reject many. Less prestigious schools often accept a higher fraction of their applicants, but some schools will reject students whose test scores, résumé, etc. are much higher than average for the school since it's likely that college is a "safety school" and the student won't actually go there. This rejection can decrease the school's acceptance rate and make it appear more prestigious. However, if the above-average student does want to attend that school, they are unable to, even though it would be good for both the college and the student.

For-profit universities and diploma mills may use techniques like this to artificially boost their ratings or use fabricated metrics and accreditation mills to give an inflated appearance of value. Predatory publishers and conferences are other techniques used to inflate the perceived value of a school or to pad curriculum vitae.

In the title text, other metrics are skewed in the school's favor:

  • Having a high standard for entry is usually associated with better or high-prestige schools; however, this is subverted by the fact that the school has only one student per class. A class of one would make (at least for most students) for a poor educational experience,[citation needed] especially in this case, where the student is apparently being micro-managed by all of the teachers at once. Even if it were a good academic environment, it could only benefit one student per year, which means the school would only have a very modest impact on the world.
  • A high number of research papers would normally indicate a high level of scientific research at the school; however, these research papers have no real content in them and are all identical, rather missing the point of a research paper - namely, to make the scientific community aware of new research.
  • A high hiring rate (percentage of students that have gotten a job after education) and a high average salary after graduation is favorable, as it is one goal for many students attending college. However, the school in question artificially inflates these metrics by having all (one out of one) of their student body be hired by them, producing a 100% hiring rate, and giving them a starting salary that is astronomically high, but not giving them enough employment time to actually gain very much income. $50 trillion/year for 10 microseconds is approximately $15.85 (= $50e12 / (365 * 24 * 60 * 60) * 10e-6 * 10) if pay is assumed to be spread constantly over the full 365 days of the year. Assuming fifty-two 40-hour workweeks would make this $66.77. Since xkcd originates in the USA, and a later comic describes short scale as "normal" vs long scale as what an "old British person" would use, trillion most likely means 1e12 (i.e., short scale), as compared to 1e18 (long scale interpretation).


[Cueball is sitting hunched over a desk writing while ten people crowd around him, five on each side, all leaning towards him. On the left side, they are Hairbun, a Cueball-like man, Hairy, Megan - who speaks, and another Cueball-like man. On the right are Ponytail, a third Cueball-like man, another Megan-like woman, Blondie, and finally a fourth Cueball-like man.]
Megan: How's the work going?
Cueball: Can you all at least stand back a little?
[Caption below the panel]:
My school tried to game the ratings by having a 30:1 faculty:student ratio

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That student from the title text would have just barely made a cent, two if they were generous and rounded up. 00:21, 15 October 2019 (UTC)

Really? My calculations have him at about 16 cents ((5 trillion x 100) divided by (10^6 x 3600 x 24 x 365.25))

Regarding above average students not getting in, the scenario described is oversimplified. I used to work in admissions for a “highly selective” university and while applicants with perfect SATs and higher than 4.0 GPAs were routinely put on the wait list (not rejected) because we assumed that they viewed us as merely a “safety school”, if the applicant showed any interest at all in actually attending, such as having come on campus for an in person interview, campus tour, or had an alumni connection, or letter(s) of recommendation, or athletic scholarship, then of course we would make an offer, and similarly if they showed any interest as cited above after being put on the wait list then they would be top of the list to get an offer from the wait list. 03:39, 15 October 2019 (UTC)

I'm pretty sure it should be $15.85 and $69.44. Although I'm not so sure now that there's 3 other answers on this page. If someone can confirm one of these and find inaccuracies in the others, go ahead and update the page. --Seaish (talk) 07:49, 15 October 2019 (UTC)

For a constant salary across the whole year, I got $15.85 as well. For paid working time it depends on the assumptions of working days per year and working hours per working day. I got 220 working days(250 official in my state-30 days of holiday, even though technically it is considered payed holiday....) and 39hours per week (8 per day, and 7 on friday), I get to $80.94. But, as stated that depends on the assumptions. --Lupo (talk) 09:48, 15 October 2019 (UTC)
"Hi!" x 5'000'000'000


I think it's a reference to "Hello, World!" test program.

It is also possible to print 5 billions of unique "Hi!" using different color (provided you have 32 bit color map for CMYK and maybe 2 differend colors of paper) (talk) (please sign your comments with ~~~~)

Unsigned Comment from Community Portal moved here


I disagree with the calculation for the amount of 50 trillion over 10 microseconds, its a lot more than the amount give,.

Wage = 50000000000000000000

Divide by 260 days for an average work year is a daily rate of = 192307692307692000.00

Divide that by 7.5, the average working day is an hourly rate of = 25641025641025600.00

Divide that by 60 for minutes in the hour to give a minutes rate of = 427350427350427.00

Divide that by 60 for seconds in the minute to give a seconds rate of = 7122507122507.12

Divide that by 1000 to give a millisecond rate of = 7122507122.51

Divide that by 1000 to give a microsecond rate of = 7122507.12

Times that by 10 = 71,225,071.23 for 10 microseconds of work, not bad.

From an ADP Payroll Specialist (talk) (please sign your comments with ~~~~)

50 trillion (in english use of the word trillion) is 5E13, not 5E19 (as you used it), so instead of $71,225,071.23 it is only $71.22 for the 10 microseconds, using your assumptions on average work days and working time. --Lupo (talk) 09:35, 15 October 2019 (UTC)
Trillion could be 1E18 in long scale, commonly referred to as Brittish, or in short scale, commonly referred to as American, it is 1E12. So the "english" use of the word trillion is ambiguous (but adding the English modifier suggests British, i.e., long scale.) I added a note to article to mention the different possible interpretations. 19:58, 15 October 2019 (UTC)
According to your wikipedia link, nearly all English speaking countries (including the UK and therefore England) use the short scale. Therefore, in contrast to my native language (German), which uses the short scale, the long scale is the "English" meaning, even though the term (English) is not scientifically correct in this context, it helps when trying to make it clear to the many people on this wiki who natively speak a language in which the long scale is the usual one. --Lupo (talk) 06:08, 16 October 2019 (UTC)
You are starting with the wage too high by a factor of a million, 50 quintillions instead of 50 trillion. (I guess you're using the British terminology instead of the US amounts) Divide all you figures by a million and you get the more reasonable $71.23, which is about what others are getting. JamesCurran (talk) 16:49, 18 October 2019 (UTC)

Is the date incorrect? The archive on xkcd says it was released on 10/14, but here it says it was released on the 15th, which would make it a tuesday comic. Landfind (talk) 14:17, 15 October 2019 (UTC)

The date was set incorrectly by the BOT that generated this page - not sure why but likely because the time of release was just past midnight GMT. I fixed it though because it is clearly the Monday comic for 10/14. Ianrbibtitlht (talk) 15:47, 15 October 2019 (UTC)
Here, a Monday the 14th seven or eight pm refresh did the trick. 17:37, 15 October 2019 (UTC)

um, "10e-6 / 3600 / 24 / 365 * 50e12)" does not mean what you think it means. are we geeks here or not? -- 08:58, 16 October 2019 (UTC)

I changed the formula. It was not actually wrong (it worked out), but the way it was displayed does not show clearly why it is applied. Also the unit $ was missing. Feel free to further edit, if this is not correct or could be done better. --Lupo (talk) 09:22, 16 October 2019 (UTC)

Where can I enlist? 14:56, 16 October 2019 (UTC)

Effect sizes by forms of instruction[edit]

Computer-aided instruction can act as a "force multiplier" increasing the effective class size ratio depending on the type of instruction used. See tables 1 and 2 here. Too tangential or ok? 12:38, 17 October 2019 (UTC)