Posts tagged with facts

Over the last century-and-a-half, mathematicians found every possible multiplication table.

The largest irreducible multiplication-table, dubbed the Monster Group, contains

808017424794512875886459904961710757005754368000000000
=
2⁴⁶×3²°×5⁹×7⁶×11²×13³×17×19×23×29×31×41×47×59×71

interlocking pieces.

That’s like the number of atoms in Jupiter.

Richard Borcherds

(modified by me)

(Source: ams.org)




An astounding 26 percent of black males in the United States report seeing someone shot before turning 12.

Conditional on reported exposure to violence, black and white young males are equally likely to engage in violent behavior.
Aliprantis, Dionissi, 2014. “Human Capital in the Inner City,” Federal Reserve Bank of Cleveland, working paper no. 13-02R.

(Source: clevelandfed.org)




We eat energy and poop entropy.
Stephen C Stearns




The $400 billion US retail grocery industry includes about 40,000 companies that operate 70,000 grocery stores (excluding convenience stores).

About 50 large national and regional chains like Kroger, Albertsons, Ahold, and Safeway hold more than 60 percent of the market. The industry is highly concentrated: 500 companies that own more than five stores control 80 percent of the market.

First Research

(Source: edsuite.com)




[Scientific theories can be accurate and even make novel predictions, whilst being ultimately wrong. Scientific theories can also be inaccurate, whilst being ultimately right.]



Consider specifically the state of ætherial theories in the 1830’s and 1840’s. The electrical fluid, a substance which was generally assumed to accumulate on the surface rather than permeate the interstices of bodies, had been utilized to explain inter alia the attraction of oppositely charged bodies, the behavior of the Leyden jar, the similarities between atmospheric and static electricity and many phenomena of current electricity.

Within chemistry and heat theory, the caloric æther … explain[ed] everything from the role of heat in chemical reactions to the conduction & radiation of heat and … standard problems of thermometry.

Within the theory of light, the optical æther functioned centrally in explanations of reflection, refraction, interference, double refraction, diffraction and polarization. (Of more than passing interest, optical æther theories had … made … startling[, true] predictions, e.g., Fresnel’s prediction of a bright spot at the center of the shadow of a circular disc: a surprising prediction which, when tested, proved correct. If that does not count as empirical success, nothing does!)

There were also gravitational (e.g., LeSage’s) and physiological (e.g., Hartley’s) æthers which enjoyed some measure of empirical success. It would be difficult to find a family of theories in this period which were as successful as æther theories. Compared to them, 19th century atomism … a genuinely referring theory … was a dismal failure. Indeed, on any account of empirical success which I can conceive of, non-referring 19th-century æther theories were more successful than contemporary, referring atomic theories.

[According to] J.C. Maxwell…the æther was better confirmed than any other theoretical entity in natural philosophy!

Larry Laudan’s A Confutation of Convergent Realism, Philosophy of Science, 48(1), 19-49

via David Corfield




Research focuses on real wages—wages that are adjusted for inflation. Getting data on wages is tricky. But accounting for inflation is even harder. (For example, workers often paid rent informally, meaning that there are few records around).

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And so it is unsurprising that researchers differ in their estimations of real wages. Some, such as Peter Lindert and Jeffrey Williamson, suggest that full-time earnings for British common labourers, adjusted for inflation, more than doubled in the seventy years after 1780. But Charles Feinstein argued that over the same period, British real wages only increased by around 30%. It’s a bit of a … mess.

Most people agree that after about 1840, real wages did better. Nicholas Crafts and Terence Mills shows that from 1840 to 1910, real wages more than doubled. Their findings are mirrored by other researchers ….

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in almost all British cities, mortality conditions in the 1860s were no better—and were often worse—than in the 1850s. In Liverpool in the 1860s, the life expectancy fell to an astonishing 25 years. It was not until the two subsequent decades that rises in life expectancy were found

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Advertising rises and falls with the economy, though how much is a matter of debate. Randall Rothenberg … points to the remarkable stability of advertising at about 2% of GDP since 1919, when the data began to be collected.

(Source: economist.com)





Since [2008], the [US] labor force participation rate (LFPR) has dropped from 66 percent to 63 percent. [Out of 314M people.] Many people have left the labor force because they are discouraged … (U.S. Bureau of Labor Statistics data indicate that a little under 1 million people fall into this category)….
…Knowing the reasons why people have left (or delayed entering) the labor force can help us [guess] how much of the ↓ might … ↑ if the economy ↑ and how much is permanent. (For more on this topic, see here, here, and here.)

The chart … shows the distribution of reasons in the fourth quarter of 2013…. Young people [usually say they] are not in the labor force … because they are in school. Individuals 25 to 50 years old who are not in the labor force mostly [say they] are taking care of their family or house. After age 50, disability or illness becomes the primary reason [given]—until around age 60, when retirement begins to dominate.
…
Of the 12.6 million increase in individuals not in the labor force, about 2.3 million come from people ages 16 to 24, and of that subset, about 1.9 million can be attributed to an increase in school attendance (see the chart below).

—Ellyn Terry

HT @conorsen
off-topic sidenote: the natural cohort —vs— year adjustments, like “the baby boom has shifted 7 years since 7 years ago” are an economic example of the covariant/contravariant distinction

Since [2008], the [US] labor force participation rate (LFPR) has dropped from 66 percent to 63 percent. [Out of 314M people.] Many people have left the labor force because they are discouraged … (U.S. Bureau of Labor Statistics data indicate that a little under 1 million people fall into this category)….

…Knowing the reasons why people have left (or delayed entering) the labor force can help us [guess] how much of the ↓ might … ↑ if the economy ↑ and how much is permanent. (For more on this topic, see herehere, and here.)

The chart … shows the distribution of reasons in the fourth quarter of 2013…. Young people [usually say they] are not in the labor force … because they are in school. Individuals 25 to 50 years old who are not in the labor force mostly [say they] are taking care of their family or house. After age 50, disability or illness becomes the primary reason [given]—until around age 60, when retirement begins to dominate.

Of the 12.6 million increase in individuals not in the labor force, about 2.3 million come from people ages 16 to 24, and of that subset, about 1.9 million can be attributed to an increase in school attendance (see the chart below).

Ellyn Terry

image

HT @conorsen

off-topic sidenote: the natural cohort —vs— year adjustments, like “the baby boom has shifted 7 years since 7 years ago” are an economic example of the covariant/contravariant distinction


hi-res




U.S. homelessness dropped nearly 17% over the past eight yearsvia The State of Homelessness in the USA

hi-res




There are very few facts I think “everyone should know”. The huge income differences across countries are an exception.

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Everyone should know that income per person in Burundi is about 1% of in the U.S. (yes, even though there’s a recession on).

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And everybody should know a rough quantitative history of the world.

13 minutes by Tyler Cowen & Alex Tabarrok