Justice Confused

Suppose that a house is robbed and police find a strand of the burglar’s hair at the scene of the crime. A suspect is in custody, and tests show that the strand matches his hair. A forensic scientist testifies that the chance of a random person producing such a match is 1/2000. Does this mean that there’s a 1999/2000 chance that the suspect is guilty?

No, it doesn’t. In a city of 5 million there will be 1/2000 × 5,000,000 = 2,500 people who produce a match, so on the basis of this evidence alone the probability that the suspect is guilty is only 1/2500.

In a 1987 article, William Thomson and Edward Schumann dubbed this “prosecutor’s fallacy.” Unfortunately, it’s matched by the “defense attorney’s fallacy,” which holds that the hair-match evidence is worthless because it increases the likelihood of the suspect’s guilt by a negligible amount, 1/2500. In fact it drastically narrows the range of possible suspects, from 5 million to 2,500, while failing to exclude the defendant, hardly cause for confidence.

Worryingly, Thompson and Schumann found an experienced prosecutor who insisted that if a defendant and a perpetrator match on a blood type found in 10 percent of the population, then there’s a 10 percent chance that the defendant would have this blood type if he were innocent and hence a 90 percent chance that he’s guilty. “If a prosecutor falls victim to this error,” they write, “it is possible that jurors do as well.”

(William C. Thompson and Edward L. Schumann, “Interpretation of Statistical Evidence in Criminal Trials,” Law and Human Behavior, 11:3 [September 1987], 167-187)

| Science & Math · Society

High Hopes

http://books.google.com/books?id=EqwCAAAAYAAJ

American life in 1980, as envisioned by Missouri attorney William McClung Paxton in his 1880 poem “A Century Hence”:

In the midst, at St. Louis, the Capitol loomed,
With lofty and glittering steeple —
The seat of a Nation, where freedom first bloomed,
Containing a billion of people.
“And now,” he exclaimed, “the whole Continent’s ours,
From Panama, North to the pole!
For naught but the ocean can fetter our powers,
Or give to us less than the whole!”

As we walked to the house, my companions reported,
That roads through the land were not found,
That men, on light wings, in the atmosphere sported,
Or walked, as they pleased, on the ground.
With the new motive power, one man could do more
Than fifty, without it, could do;
So people were able to add to their store,
And be generous, noble and true.

An order for supper, by telephone, now,
Had scarcely been made, by my host,
When in sprang a servant, I cannot tell how,
With coffee, ham, biscuit and toast.
He’d come from St. Louis, three hundred miles out,
With dishes delicious and rare;
There were venison, and turkey, and salmon, and trout,
With pine-apple, orange and pear.

When supper was ended, I found it still light;
I looked for a lamp, and found none;
I stepped to the door, and looked forth on the night,
And lo! every house had a sun.
Above me in splendor, surpassing the moon,
A disk, in the heavens gave light;
And neighboring orbs gave the brightness of noon,
And scattered the darkness of night.

By reflectors, the light of these beacons was cast,
On parlor, and chamber, and hall;
And candles and lamps were consigned to the past,
And light, like the air, was for all.
Now worn by the scenes of the day, I need rest,
And find it in slumber elysian;
But rise in the morning, perplexed and distressed;
‘Twas all but a beautiful vision.

| Poems

More Attachable Mirrors

https://www.google.com/patents/US790537

In 1904 Emmie Alice Thayer lamented that a lady had to hold a hand mirror while attending to her hair or addressing the fit of her garment. The answer, she decided, was to wear the mirror by attaching it to her ears. Kudos.

In the same vein, in 1950 John Kozloff invented a “mirror-attached spectacle frame” (below) to free one’s hands for applying cosmetics or shaving. If you’re nearsighted they can even be fitted with glasses. With a pair of these Narcissus wouldn’t have been tied to that boring pool …

See Self-Regard.

https://www.google.com/patents/US2502224

| Technology

Self-Reproach

http://commons.wikimedia.org/wiki/File:The_gout_james_gillray.jpg

Driven from bed by pain in his toe one October night, Ben Franklin imagined a parley with his tormentor:

FRANKLIN. Eh! Oh! eh! What have I done to merit these cruel sufferings?

GOUT. Many things; you have ate and drank too freely, and too much indulged those legs of yours in their indolence.

FRANKLIN. Who is it that accuses me?

GOUT. It is I, even I, the Gout.

FRANKLIN. What! my enemy in person?

GOUT. No, not your enemy.

FRANKLIN. I repeat it, my enemy; for you would not only torment my body to death, but ruin my good name; you reproach me as a glutton and a tippler; now all the world, that knows me, will allow that I am neither the one nor the other.

GOUT. The world may think as it pleases; it is always very complaisant to itself, and sometimes to its friends; but I very well know that the quantity of meat and drink proper for a man, who takes a reasonable degree of exercise, would be too much for another, who never takes any.

FRANKLIN. I take — eh! oh! — as much exercise — eh! — as I can, Madam Gout. You know my sedentary state, and on that account, it would seem, Madam Gout, as if you might spare me a little, seeing it is not altogether my own fault.

GOUT. Not a jot; your rhetoric and your politeness are thrown away; your apology avails nothing. If your situation in life is a sedentary one, your amusements, your recreation, at least, should be active. …

FRANKLIN. Oh! oh! — for Heaven’s sake leave me! and I promise faithfully never more to play at chess, but to take exercise daily, and live temperately.

GOUT. I know you too well. You promise fair; but, after a few months of good health, you will return to your old habits; your fine promises will be forgotten like the forms of the last year’s clouds. Let us then finish the account, and I will go. But I leave you with an assurance of visiting you again at a proper time and place; for my object is your good, and you are sensible now that I am your real friend.

As the dialogue shows, Franklin had understood the risks he was incurring — at 28 he had written in Poor Richard’s Almanack:

Be temperate in wine, in eating, girls, and slouth;
Or the Gout will seize you and plague you both.

But he accepted the consequences. Three years before his death he wrote, “People who live long, who will drink of the cup of life to the very bottom, must expect to meet with the usual dregs, and when I reflect on the number of terrible maladies human nature is subject to, I think myself favoured in having to my share only the stone and the gout.”

| Literature

Season’s Greetings

http://commons.wikimedia.org/wiki/File:Der_afrikanische_Elefant.jpg

Apparently bored in December 1936, the eccentric Gerald Tyrwhitt-Wilson, 14th Baron Berners, placed an advertisement in the personals column of the London Times:

“Lord Berners wishes to dispose of two elephants and one small rhinoceros (latter house-trained). Would make delightful Christmas presents.”

When a newspaperman telephoned, Berners took the call himself, pretending to be the butler. “Actually, I haven’t seen the rhino, myself, sir,” he said, “but it’s often about the house. It’s quite gentle, I’m told. The weather was getting too cold for the elephants, so I’m glad they’ve gone. They went on Saturday. I understand Mr. Harold Nicolson has bought one and Lady Colefax the other. I hope they have good homes.”

A bewildered Nicolson found himself insisting, “I have NOT bought an elephant! I do not intend to buy one! I do not want an elephant, and I have nowhere to put an elephant! This looks like a joke. I have known Lord Berners for twenty-five years, but I don’t feel friendly to him this morning. I do not want an elephant, have never wanted one, and I have not bought one.”

More Berners mischief.

| Hoaxes

“Baby Food”

http://www.julianbeever.net/index.php?option=com_phocagallery&view=category&id=2:3d-illusions&Itemid=7

The baby is real; the lobster and the bowl were drawn in chalk on a Hartlepool sidewalk by artist Julian Beever. Beever draws in anamorphic perspective, so his work appears distorted when viewed from most angles (below) but creates an illusion of three dimensions when seen from one privileged viewpoint.

“I expected more complaints when I posted this on my website of drawings,” he writes, “but surprisingly there have been very few. It shouldn’t be taken too seriously.”

http://www.julianbeever.net/index.php?option=com_phocagallery&view=category&id=2:3d-illusions&Itemid=7

| Art

Fixing Dates

In 1899, British statistician Moses B. Cotsworth noted that recordkeeping could be greatly simplified if each month contained a uniform number of whole weeks. He proposed an “international fixed calendar” containing 13 months of 28 days each:

international fixed calendar

This makes everything easier. The 26th of every month falls reliably on a Thursday, for example, and statistical comparisons between months are made more accurate, as each month contains four tidy weeks with four weekends. (Unfortunately for the superstitious, every one of the 13 months contains a Friday the 13th.) A new month, called Sol, would be wedged between June and July, and an extra day, “Year Day,” would be added at the end of the year, but it would be independent of any month (as would Leap Day).

In 1922 the League of Nations chose Cotsworth’s plan as the most promising of 130 proposed calendar reforms, but the public, as always, resisted the unfamiliar, and by 1937 the International Fixed Calendar League had closed its doors. It left one curious legacy, though: George Eastman, the founder of Eastman Kodak, was so pleased with Cotsworth’s scheme that he adopted it as his company’s official calendar — and it remained so until 1989.

| Science & Math · Society

Unquote

“The thoughts that come often unsought, and, as it were, drop into the mind, are commonly the most valuable of any we have, and therefore should be secured, because they seldom return again.” — John Locke, letter to Samuel Bold, May 16, 1699

| Quotations

Parting Words

http://commons.wikimedia.org/wiki/File:Edouard_Manet_059.jpg

Dear Betty:

I hate you.

Love,

George

— Suicide note quoted in Marc Etkind, Or Not to Be: A Collection of Suicide Notes, 1997

From the agony I have been through for no reason whatever I can only come to the logical conclusion that if there is a god that he is not so good as is made out.

— A young clerk’s suicide note, quoted in Olive Anderson, Suicide in Victorian and Edwardian England, 1987

Kids, if there are any errors in this letter, I did not proof it carefully.

— From the 1985 suicide note of Cleveland superintendent of schools Frederick Holliday, who shot himself in a high school stairwell on learning that the school board planned to oust him

In 1930, San Quentin death row inmate William Kogut removed one of the hollow steel legs from his cot, stuffed it with red pips torn from from several packs of playing cards, and soaked them with water. Then he plugged one end of the pipe with a broom handle, rested it on a kerosene heater, and held the open end against his head. The red ink contained enough nitrocellulose to cause an explosion that drove the card fragments into Kogut’s head, killing him.

His note to the warden said that he was punishing himself for the murder of Mayme Guthrie. “Do not blame my death on any one because I fixed everything myself,” he wrote. “I never give up as long as I am living and have a chance, but this is the end.”

| Death