What's significant about that? - It's the highest number of pages in Category:yyyy births

Results below. First two columns are every ten years back to 1440, second two are year by year back to 1970.

Explanation? Clearly there won't be many articles about one year olds or two year olds. It takes age to gain notability. Thus the number of articles will rise until - as in Wikipedia - we reach people born in 1981, people who are now (in 2009) about 28. This is when you are most notable.

Sadly after this your notability decreases consistently by about 10% for every decade you are older (or deceased).



2000 42 2000 42
1990 2572 1999 48
1980 7868 1998 78
1970 6,278 1997 89
1960 5512 1996 113
1950 5463 1995 140
1940 4403 1994 198
1930 3768 1993 383
1920 3406 1992 715
1910 2925 1991 1394
1900 2471 1990 2572
1890 2077 1989 3686
1880 1701 1988 4880
1870 1453 1987 5714
1860 1228 1986 6743
1850 1010 1985 7475
1840 927 1984 7733
1830 780 1983 8010
1820 795 1982 8140
1810 726 1981 8147
1800 622 1980 7868
1790 437 1979 7681
1780 419 1978 7138
1770 343 1977 6939
1760 290 1976 6778
1750 281 1975 6503
1740 242 1974 6345
1730 208 1973 6322
1720 153 1972 6210
1710 141 1971 6240
1700 119 1970 6278
1690 110
1680 111
1670 85
1660 94
1650 99
1640 109
1630 107
1620 117
1610 122
1600 112
1590 99
1580 92
1570 67
1560 101
1550 101
1540 93
1530 70
1520 76
1510 57
1500 69
1490 53
1480 51
1470 41
1460 36
1450 27
1440 24

Sports?

And pop music I suppose. However, there are surely as many older sports-people as 28 year old ones. Or does your notability decrease as you become an old sportsman or popstar. Clearly so.

It would be painful, but interesting to repeat the exercise with Chamber's Biographical to see what decay function applies there.

My guess is female sex-symbols of one sort or another in entertainment (example: Beyoncé was born in 1981). I hope they all enjoy it, since it'll all be downhill for this particular cohort, after 2011.





This is when you are most notable to WP editors, who are male nerds writing about pop icons. Which is 28-yo females like Beyoncé.

If they were interested in Nobel laureates or leaders of state or captains of industry or leaders of academia, of course it would be very different. Notability on WP is what the male small-brain dictates. You know-- the one all men have toward the rear, like Stegosaurus?

Which Nobel laureates lack articles?

All the ones born in 1981.

You can argue that the numbers of Nobelists are limited, but there are not articles on all college associate and full professors in the US. Sports and entertainment figures are covered far more comprehensively than academic and industrial figures.

But which one does YOUR economy and nation's progress depend on?

I think is almost exclusively the answer. Stubs are consistently created for every player to appear in any game of professional leagues and 28 is about the right age for people making it to the top in many sports. No one bothers to create articles on people who played one game of baseball in 1956, so naturally it declines as the date moves further away. More than 19.8% of all Wikipedia biographies are of athletes (I would personally estimate the figure at around 23%, but that involves some fuzzy math).

How will the curve change shape in the future? We can probably assume that the articles written about 28 year olds now will remain at the same number. Assuming that future 28 year olds are equally notable as current 28 year olds, this implies the curve will turn into a straight line, memorialising the time Wikipedia was invented. If Wikipedia had been invented in 1928, we would see a straight line stretching back to 1900, then collapsing, reflecting the decrease in notability of people born before 1900.

http://www.youtube.com/watch?v=OANwX8pFC8A&feature=related

This makes you sad, O Mighty Arbcomdude?

Then why don't you start pushing for some of that reform stuff?
You could start with BLP reform, that would help remove the bias.

I guess that what makes him sad is he'll be 30 in 2011.

That's pretty intense. See, I always felt that there's only a finite amount of articles on Wikipedia, and not every article gets assigned a date (for example, particularly in antiquity, it's hard to get an exact year on certain people). My feeling is that one year has to be the one with the most articles, and it just happens to be 1981. It seems like more of a coincidence to me rather than a fundamental disrespect for academics, scholars, etc (not that Wikipedia doesn't have that problem either).

But that won't be as bad for him, as he's a man and will thus remain attractive for many decades after that point, as is typical of our sex. It's a matter of attitude. We just look good most of the time.

Women seem unduly concerned about such things. I was recently dragged naked in front of a full-length oval tilting dressing mirror that my woman had bought at a garage sale (no, this happened long after we got it home). And I discovered it was a circus mirror! And now, the amazement: whereas, I myself have aged very little in the last couple of decades, this clownish evil thing acted in the VERY manner of The Picture of Dorian Gray. My image was aging, but not me. Especially I could see this when I turned sideways, when it appeared that my body (which is a temple) was tending toward, well, landfill.

"What do you want with this silly thing?" said I, pointing at the circus mirror.

So she stood there, along side me.

"Must be a height-distortion thing, as I recognize you," I said. "And, also, I am reminded that you've been getting a bit broad in the beam, lately."

I won't report the rest of this, as it was highly uncivil, and only would illustrate my view that females are fundamentally obscessed with images, and also highly excitable for no really good reason. Probably it's best that only a small fraction of WP editors are supposedly female. They'd do better on COMMONS.

Milton

If you are saying it's random, that's nonsense. If you chart the numbers then you get a very smooth curve, except for a few slight bumps here and there, which seem to be explained by important historical events creating notability for people who otherwise might have remained un-notable. The curve can also be explained mathematically, at least for the part where notability declines - there is an exponential decay of about 10% every decade. Generally any phenomenon that is smooth and has a mathematical explanation, is not random. Indeed, that's practically a definition of non-randomness.

It's more of a speculation as to why the curve has that shape. Clearly the sharp rise from 0 to age 28 reflects the fact that your probability of notability rises with age. The fact there is exponential decay after that clearly reflects the tendency to forget - everyone becomes non-notable with time. Sad.

Given that, how do we explain the hump at age 28? It must be a Wikipedia phenomenon. Having checked in Chambers biographical, there is almost no one of that age. Most are very old or dead people.

My final observation is that there is a further piece of mathematics driving it. Given that articles about people aged 28 will remain in Wikipedia, which seems reasonable, and assuming that people will not become on average more notable over time, it follows that the curve will develop a 'plateau'.

Britney Spears was born in 1981... who could be more notable than that?

Kelly Clarkson misses by one year, born in 1982.

Thanks, Milton! Thanks sexist societal norms!

Glad to help. And yes, Britney Spears is also a 1981. Very few pro atheletes achieve height of fame at age 28 (Olympics of course are different --it's probably actually younger for everything except endurance sports-- but far fewer atheletes are Olympians). But height of desirability and fandom, is something else slightly different. The one is cumulative. The other is RIGHT NOW. These are tribute bios by wankers.

But if you have a way to check the sex of the BLP subjects, you have a way to see if my theory is good, or yours, or a mix. If it's pro atheletes, it will be predominantly male. If entertainers, given that the writers on WP are mostly male (albeit some of them, er, light on their feet) the 28 year-old bios will be at least half female. Perhaps predominantly.

A random sample of 100 of the 1981-born BLPs will tell us, just on inspection. Whoever noticed this, could you post the first 100, starting in alphabetical order or any other order which doesn't depend on you selecting them by occupation cat?

I tried a similar exercise with Chambers' Biographical using 160 articles, and plotted a distribution. Nowhere near enough data (I may try again sometime) but two things are clear:

1. you have to be a lot older to achieve notability in Chambers. The most recent birth year was 1959, and 'peak notability' is for those born in the 1870's, i.e. 139 year olds.

2. The decay factor seems less pronounced, i.e. your notability declines less per decade than in Wikipedia.



I tried the first 20 and it is overwhelmingly dominated by sports. Stubs.

I didn't say it was random. I barely know what that word means. I'm just not convinced that it's intentional or deliberate or purposeful on the part of so many people.



That makes sense. I never thought it was random. I just don't understand why it's significant. I'm sure you would agree that if you tried to assign a birth year to every biography on Wikipedia (which as far as I can tell, hasn't been done yet and isn't even possible), there will have to be one year that has more than everyone else since there isn't an equal distribution of so-called "notable" people in every year.



I thought it was just simple laziness. It's actually pretty easy to find information on someone like Britney Spears. It's a lot harder to find information on someone like, say, Diotama. A truly dedicated encyclopedia would take the time to research people even if they have to go to an actual library and not rely heavily on Google hits for sources. Then again, no one has ever accused Wikipedia of having a dedicated research staff.

By the way, how many biographies actually have birth dates on them? It could simply be that people born more recently have more reliable or easier-to-cite birth dates. That and laziness might explain why recentness and notability seem to correlate more than on better encyclopedias.

You'd get better results with a larger sample, and that would be a trivial task if only enwiki categorized people by sex. Over on the die Deutschsprachigewiki for example, bio articles belong directly to kategorie "Mann" or "Frau".

Twenty-eight doesn't seem so unreasonable. In the wild triangular world of sports-music-n-acting one can easily be famous, dead, and buried by that age if they know what they're doing.

Is it true that people born more recently have more reliable or easier-to-cite birth dates? That would be fair enough if we were talking about the difference between the 18th and 19th century. But virtually everyone born in Britain or America in the 20th century will have a verifiable birthdate unless they choose to conceal it.

Can you imagine how many disputes that woukd cause on the English site?

- "But I have a reliable source that uses "he" to refer to Marie Curie."

- "Just because someone has a female name and went to a girls school, you can't assume he's female. That's original research."

More nonsense. If you are saying that there is an approximate mean value for any year, with a random fluctuation around that mean, so that one year will have the greatest number, you haven't looked at my figures. These show a very smooth curve with no significant random fluctuations, such that there is no mean value. notability clearly and markedly decreases over the age 28, with a 'decay' of 10% every decade. I.e. if there are 100 notable people of one decade, the previous decade will have 90 notables, the decade before that 81, and so on. This is known as exponential decay.

The function is so pronounced that there must be an explanation for it. The simplest being that 'recentism' - the tendency to overestimate the notability and interest of recent phenomena, is more pronounced in popular culture than in serious research. Perhaps there is another explanation.



Correct. Virtually all birth dates of notable people after 1500 are reliable. Before that it is more difficult and relies on guesswork and inference.

Something nobody seems to have mentioned is that there has been a steady growth in the world population for the last 100 years or so - so if one assumed that the proportion of the population who are "significant" remains roughly constant, then a steady growth followed by a sudden drop off (when we reach the stage where people are too young to have made an impact) is surely exactly the pattern one would expect to see in any collection of biographies. I strongly suspect that you'd see the same pattern in any biographical collection (aside from those like the Dictionary of National Biography which have a "must have been dead for five years" rule).

I looked at the decades from 1930 to 1980, sampling 66 individuals from each year alphabetically, and sorted by some very crude classifications. Results in the table below. Very much what you would expect. Sports dominates 1980, but falls rapidly after that. Very few politicians in 1980, because there aren't many young politicians. Peak decade for them is 1950, probably because you make your mark when in your 50's. Scientists, artists and academics become notable in their 40's and onwards. I'm afraid this editor loses the formatting.

1980 1970 1960 1950 1940 1930
scientist 0% 3% 3% 2% 8% 11%
academic 0% 2% 6% 5% 6% 8%
artist 0% 5% 3% 8% 3% 11%
acting 6% 11% 9% 3% 9% 8%
politician 3% 8% 18% 29% 23% 14%
sports 68% 47% 26% 11% 18% 15%



I had wondered about that but it makes no sense with the mathematics. The decay is exponential and smooth and generally does not follow the patterns of population growth in Europe and the world since the 1800's. Population is no guide to notability. American population grew rapidly in the 1800's but there was no corresponding growth in notable American writers and academics in that period (that occurred later).

Notability is closely connected with cultural and imperialistic phenomena.



(1) Standard reference works (unlike Wikipedia) have a similar rule. Ask yourself why there is such a rule.

(2) As pointed out above, the pattern is entirely unrelated to population statistics. You should also consider the factor of the rise in universal education which began in the mid nineteenth century. But this would not explain the Wikipedia statistics, e.g. the proportion of scientists remains relatively constant, and even rises with age.

Maybe the real question is why there are so few notable actors born 1950.

A city with a hundred TV stations is going to have more TV stars than the same city 30 years ago with three TV stations; the current English football league of 92 teams will produce more professional footballers than the old football league of 18 teams; an increase in literacy and the number of bookshops means a greater number of successful authors; the increase in the number of independent countries means more legislatures, and hence more politicians to fill them; the huge growth in the size and numbers of universities in Europe and Asia over the last 20 years means more academics; the spread of religions, as evangelical Christianity spreads in Africa and Asia and Islam spreads in Europe and North America, means more religious leaders... Add to that that it's relatively easier to source recent events (if I wanted to write a biography of every contributor to Reynold's News it would involve digging through numerous dusty libraries and archives, and may be impossible due to the German bombing of the British Library's newspaper archive; if I wanted to write a biography of every person who had appeared on Gilligan's Island I could get at least basic material without leaving my seat). Oh, I don't doubt that some of the spurt is due to systemic bias, but do you see where I'm going with this?

I don't see where you are going. The figures above clearly contradict what you say. The notability of sports stars rapidly decreases with their age. The notability of academics increases with age. With the 'rapid expansion' of the number of universities, you would have expected the opposite for the academics. A reasonable explanation is that the average Wikipedian is obsessed with ephemeral subjects like minor league sports players. The few Wikipedians who are interested in academic subjects rely on tertiary sources which tend to be dated.

And has there been a 'rapid expansion' in universities? My impression is that many institutions which were around 20 years ago but weren't called universities (polytechnics, teacher training colleges) are now called universities. How does that make them more notable?

This http://en.wikipedia.org/wiki/Category:Acad..._United_Kingdom suggests that the traditional classification still applies (look at the number of pages devoted to Oxford university, by contrast with the old polys).

I do agree with you about the ease of sourcing recent events.

The growth in the number of students in higher education - at old universities and former polytechnics combined - has shot up in recent years in every major country other than Spain; the current rate of increase is 50% per decade. Oxford, Yale etc are always going to have a greater number of "notable academics", because they recruit people who have become established elsewhere, but I don't think you can dispute that it's going to cause a demographic bulge; it may not be the direct cause of the 1981-births peak (not many academics outside a few mathematicians reach their peak in the late 20s) but it surely is having an impact on the disproportionately western student group who both write Wikipedia and are its biggest users.


No, that ties in exactly with what I'm saying, I just said it in a roundabout way. There are now 216 countries in the world, and every one of them has a national league in most sports and their own music chart, vastly increasing the pool of people who are (a) automatically "notable" by Wikipedia standards and (b) easily created with at least basic data. If you look at the articles on which people are actually writing, as opposed to the bot-created stubs - for example, those articles at WP:GA - you get a far more balanced picture.

What, like, say, Jimmy Wales?


We don't have a reliable birthdate or birthplace for Chester A. Arthur, even though he was President of the United States a while back. While it's probably true that most "notable" people have "settled" birthdates, in quite a few of those cases the "settled" birthdate isn't really all that "reliable".

You missed the sentence that followed, which was that academic notability apparently increases with age. That is not consistent with your assertion about the huge 'growth' of higher educational institutions. However your second point, about the availability of information, is correct. It is much harder to get information about 'high' culture than 'low' culture. Add to that the average Wikipedian's interest in 'low' culture, and I think that explains what we are seeing pretty well.



This increase is largely explained by the use of cheap 'adjunct' teaching labour. The result is also that most 'students' can't get jobs.

Such as Nancy Reagan, Charo, and any sports figure originating in the PRC.

Certainly among academics, you are most unlikely to be notable before the age of 30. I would guess that even among living academics the peak would be nearer 60. Of course, if you include dead academics the peak birth year would be even earlier. Undoubtedly, British academics are dramatically under-represented. Of all those whose work I can claim to know enough to judge and who I believe meet WP:PROF, fewer than 10% have articles. I was minded to create 100 or so articles then I thought why should I?

This reminds me of the way that the closing credits on old films would occupy a single screenshot, appearing for a few seconds. Some time in the 1970's this all changed and now there is an endless list of the technicians (grips, gaffers, make-up artists, animals, police department officials, inanimate objects) who were remotely involved in the making of the film, taking several minutes.

Has the notability of such people increased since the 1930's?

No, but they've unionized.

Apropos of not much, my first born was born this date in 1981. In the US we write the date as 9/27/81. In the first minute after birth an epiphany hit me. I turned to my wife and said "Do you realize A____'s birth date is 3 squared, 3 cubed, 3 to the fourth?"

If she had had the strength I think my wife would've slugged me.

Fortunately eldest daughter is not notable.

Yes. Well, we all have our hobbies. I'm reminded of Professor Hardy going to the see his far more talented protégé Ramanujan, who is ill (pretty much a Good Will Hunting story, but true), and remarking that his cab number 1729 was not very interesting (what touchy feely conversations these mathematicians have). And then Ramanujan says in his East Indian accent: "Oh, no, Hardy, it is a most interesting number! It is the smallest number which can be expressed as the sum of two cubes, in two different ways..."

1729 = 1^3 + 12^3 = 9^3 + 10^3

But I'm sure Hardy was more edified by this than your wife was.

Cool story, bro.

Well for a small but not particularly biased sample of what "notable" 28-year-olds do for a living, we can look at the 19 article subjects born on this mathematically significant day:

1. Neha Ahuja, olympic skier
2. Lakshmipathy Balaji, cricketer
3. Patrick Bengondo, footballer
4. Sophie Crumb, comics artist
5. Mike Esposito (baseball), major-league pitcher
6. Espen Hægeland, footballer
7. Guus Hoogmoed, olympic sprinter
8. Yekta IbrahimoÄŸlu, footballer
9. Giovanni Lanaro, olympic pole-vaulter
10. Ida Ljungqvist, playboy bunny
11. Brendon McCullum, cricketer
12. Beth Morgan (cricketer), cricketer
13. Mitar Novaković, footballer
14. Andrej Pečnik, footballer
15. Vince Perkins, minor-league pitcher
16. Jeremy Stenberg, motorcycle stunt guy
17. Cytherea (person), porn star
18. Nene Tamayo, Big Brother (Philippines) contestant
19. Mirjam Weichselbraun, tv host

Looks like 14 for sports and 5 for the... uh... "humanities" (yeah that's it).

I assume this is roughly the distribution we expected to see?

[pedant]Ramanujan was from India, not the East Indies.
[/pedant]

In America where we still have politically incorrect films about Cowboys and Indians, we sometimes say "East Indian" to refer to people from India.

An "Indian accent" here, is thus the kind you hear from the great actor Sal Mineo in Cheyenne Autumn.

This one's for you, Horsey:

Wowie! Talk about two countries divided by a common language! So how do you describe people from the East Indies?

Really-far-East Indians. What do you call them?

I hear that in the UK you have a "near East" and a "far East" according to how far it is from London.

Here in the US, we just call all that stuff "many-day-travel-heap-far-place." All same.

East Indians.

Indubitably. I'm pretty impressed myself. Guess that's why Ramanujan is notable and I'm not.


Eldest daughter does wear a bunny suit

But she's a state biologist and tests blood and tissue samples for all kinds of nasties


I suppose I would expect more "humanities". Would be mildly interesting to run some stats.

"Southeast Asian" I thought!

In the real world I doubt I've seen "East Indies" printed outside a history textbook. Not something you'd drop into casual conversation lest they look raise an eyebrow and say "oh Warren Park eh?"

No, really, we don't have an "East Indies" in the US, just East Indians, meaning people from India. The East Indies thing is for the colonialists of the places East-of-India, which we never were. As WP informs one, the British East Indies refers to Malaysia, the Dutch East Indies means Indonesia, and Spanish East Indies means the Philippines. I can't keep it all straight. I prefer the latter names. And no "West Indies" for my Caribbean.

That will cause a problem for Test cricket.