Archive for October, 2021

Monday Morning Math: Adolphe Quetelet

October 25, 2021

Adolphe Quetelet (pronounced Ket-eh-lay) was a Flemish Scientist who was the first to use the normal curve.

Born in Ghent, France in1796, Adolphe’s father died when he was just seven years old. At the age of 17, after his own schooling at Lyceum in Ghent where he excelled in mathematics, he took a job teaching mathematics at a school in 1813 to support his family. He was appointed a mathematics instructor at the College in Ghent in 1815 at the age of 19.

While at the College of Ghent, Adolphe was influenced by Garnier who encouraged Quetelet’s deeper studies in mathematics. He went on to earn a doctorate from the University of Ghent in 1819 with a dissertation on conic sections. After graduating and at the age of 23, he was appointed chair of elementary mathematics at the Athenaeum in Brussels. While he taught mathematics, Quetelet had a strong interest in astrology and lobbied for an observatory in Brussels. While visiting Paris on a fact-finding mission for the observatory, Quetelet learned the importance of statistical methods in astronomy.

As a result of his “zeal for statistics,” Quetelet identified society as a topic and studied and wrote papers on social statistics and in the course of that work was the first to use the normal curve/distribution and used what astronomers knew as the error law or bell curve on human populations. He also introduced the height/weight measure that we know today as the body mass index (BMI). He used the idea of an average as a central value. He collected statistics on crime and mortality and improved census taking for the government.

In 1855 Quetelet suffered a moderate stroke and never fully recovered suffering from a poor memory which negatively impacted his writings. Quetelet died in 1874.

Sources:
https://mathshistory.st-andrews.ac.uk/Biographies/Quetelet/
https://www.famousscientists.org/adolphe-quetelet/

Compiled by Tracy Lyn Lause

Monday Morning Math: Florence Nightingale

October 18, 2021

The mathematician this week is Florence Nightingale (1820-1910). WHAT??? Yes, she is most known for being a nurse, but many do not realize that Florence Nightingale was also a mathematician and data collector and is known to be one of the most prominent statisticians in history. Quite something for a woman in the 1850s.

Born in 1820 to wealthy parents, as a child, her father fostered her education in history, philosophy and literature, but she was gifted in math and the languages. Florence Nightingale was grounded in her religious beliefs and said she was “called by God” to “reduce human suffering” and as such pursued a career in nursing.

It was as a nurse during the Crimean War (1853-1856) in the Scutari, Turkey Barrack Hospital in 1856 that she collected data on the care of the wounded soldiers, recording information about how the soldiers died and “bringing order and method to the hospital’s statistical records.” The analysis of this data prompted Florence Nightingale to demand better care and more food and supplies for the soldiers in the hospital as well as the implementation of better hygiene and cleaning procedures. Florence Nightingale used her data to show the need for standards of care and “her accomplishments reduced the mortality rate to about 2 percent.”

Thus, it is said “her work in statistics saved lives.” She also earned the title “the Lady with the Lamp” from the soldiers for whom she cared since she made rounds in the evenings carrying a lamp through the hallways.

Florence Nightingale is credited with being an innovator in displaying statistical data through graphs (infographics). She uses a Coxcomb graph or Rose Chart (similar to a pie chart) in 1858 to illustrate the improvements to the mortality rate of soldiers in the hospital after her cleaning and sanitation procedures were adopted. Two years after returning from Crimea, Florence Nightingale was elected the first female member of the Statistical Society in 1858.

Sources:
https://www.britannica.com/biography/Florence-Nightingale
https://www.history.com/topics/womens-history/florence-nightingale-1
https://thisisstatistics.org/florence-nightingale-the-lady-with-the-data/
https://www.sciencemuseum.org.uk/objects-and-stories/florence-nightingale-pioneer-statistician

This post was generously written by our own Tracy Lyn Lause. Thanks Tracy!

Monday Morning Math: Alan Turing

October 15, 2021

(Monday morning Math – this week on Friday because Hello Midterms!)

Our mathematician this week is Alan Turning.  He was born in London, England, on June 23, 1912 and studied mathematics at the University of Cambridge.  After his graduation he wrote a paper called “On Computable Numbers, with an Application to the Entscheidungsproblem” which showed the depressing sounding but powerful result that not every true statement is provable in a mathematical system.  During this time he also invented the Turing machine, which is an abstract computer (as opposed to an actual physical computer) that performs logical computations.

Turing earned his PhD at Princeton University in 1938 and returned to Cambridge where he began working on codebreaking.  The following year, at the start of World War II, he moved to Bletchley Park where he developed methods for breaking various codes intercepted from the Germans and, even after the war continued to make significant contributions to work in artificial intelligence.

While Turing was recognized for his work he was also persecuted because of his sexuality:  in 1952 he was convicted of being homosexual and given the choice of going to prison or taking hormones as a chemical castration. He chose the latter; he also lost his security clearance as a result of this conviction.  Turning continued to do work in physics and biology, but died on June 7, 1954, from self-induced cyanide poisoning.  In 2009 the British government officially apologized for how they treated him and in 2013 Turing was posthumously pardoned. 

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(This image of Alan Turning was made by Stephen Kettle from Welsh slate is sharable under creative commons, whereas the photos I could find still have a copyright.)

You can find more information about Alan Turing at BritannicaWikipedia and turing.org.uk  And to end on a more positive note, these days there is Spectra, the Association for LGBTQ+ mathematicians and their allies.

Monday Morning Math: Whose Triangle?

October 4, 2021

Today’s snippet isn’t a who, or at least not a single who.  There is a triangle that many people learn about in school, since it pops up in some interesting places.  It starts off like this

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with each number equal to the the sum of the two numbers above it.  It’s a pretty interesting triangle, but who first came up with it?

In the United States it is often referred to as Pascal’s triangle, after Blaise Pascal.  This isn’t so much because he invented it (he didn’t) but because he wrote so much about it, in a book entitled Treatise on the Arithmetical Triangle (but in French, so Traité du triangle arithmétique), written in 1654 and published 11 years later.  Here’s how he wrote it:

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But the Triangle was known before that.  Here’s a picture from 100 years earlier, in  a book by Niccolò Tartaglia in Italy:

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Here’s one from 250 years before THAT, by Zhu Shijie in his book Si Yuan Yu Jian from 1303 in China:

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There’s another version around this same time period by Omar Khayyam in Persia (modern day Iran) although I didn’t have a picture of that to include. But he wasn’t the earliest either: here’s one from 550 years before THAT (so roughly 900 years before Pascal)

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This is from a manuscript in Raghunath Library, Jammu and Kashmir, in India from 755 (according to Wikipedia) where the figure was called the Staircase of Mount Meru (Meru-prastaara).  This, too, is unlikely to be the earliest: there are indications that the earliest manuscripts showing the arithmetic triangle are copied from even earlier ones.

So who first described this Arithmetic Triangle?  We don’t know, although we can say with assurance that it was well over a thousand years ago.

More information can be found at wikipedia, at  britannica.com