Isegoria

Art History Can Trade Insights With the Sciences explains a scientific discovery the art historians didn’t want to hear about:

The controversy over Hockney and Falco grew out of Hockney’s discovery of a sudden shift toward naturalism in the 1420s and ’30s in Flanders. Hockney claimed that the shift was too abrupt to have occurred without the use of optical aids that allowed artists to project images of the 3-D world onto a canvas and trace them. With the entry of Falco, evidence took the place of opinion. Falco pointed out that concave mirrors can serve as lenses that project images and that such mirrors were available as early as the 13th century. He went on to analyze anomalies in certain paintings that were consistent with the use of a lens and — most important — difficult to explain otherwise.

Lorenzo Lotto’s painting called “Husband and Wife,” of 1523-24, depicts a carpet with a complex geometric design covering a table. The carpet recedes into space. Falco demonstrated that the lines on two of the borders of the design start off receding toward one vanishing point and then move slightly toward another vanishing point. It’s strange that there are two vanishing points. It’s even stranger that the vanishing points of both borders shift at approximately the same depth into the scene.

But Falco offered an intriguing (somewhat technical, very precise) explanation: Lotto’s use of a lens led to systematic and predictable errors. Falco calculated that Lotto must have placed his lens 150 cm. from the carpet he was painting and 84 cm. from the canvas onto which he was projecting the image of the carpet. He also calculated the focal length (54 cm.) and diameter (2.5 cm.) that Lotto’s lens had to be. Those calculations were all derived from one measurement: a comparison of the shoulder width of the woman in the painting with the average shoulder width of actual women today. The difference in size between the two widths showed how much the objects on canvas were reduced — in this case, by 56 percent.

When a lens is used to project an image, the less that image is reduced in size, the lower the depth of field that the lens can project. Because Lotto was projecting images reduced in size by only 56 percent, he had a problem — he could project only part of the image onto the canvas. Once that part was traced, he would have had to move the lens just a tiny bit to focus farther back. Hence a slightly different vanishing point and a slightly different magnification — both subtle errors. Falco calculated exactly how much the two vanishing points would diverge and the magnification would decrease, and his calculations agreed to within 1 percent with measurements he made from the painting. Falco tested his lens hypothesis against many paintings, and found other instances in which the errors were mathematically predicted by the use of a lens. His hypothesis did not rely only on such predictions; he also found that sometimes highly complex, three-dimensional, nongeometrical objects were rendered so precisely that use of a lens was highly probable. But the litmus test of the lens hypothesis was Falco’s ability to so precisely predict nonrandom errors.

I now have to check which state I’m in before phoning home — or I have to finally get a hands-free headset. From WSJ.com – As Industry Pushes Headsets In Cars, U.S. Agency Sees Danger:

Earlier this month, New Jersey and Washington, D.C., joined New York in requiring drivers to use headsets or other so-called hands-free devices when they talk on cellphones.

Pushing hands-free headsets may not make phones safer though:

A sizable body of research concludes that headsets and speaker-phones don’t improve safety because it’s the mental distraction of talking on the phone, not holding it, that causes the danger while driving. And recent research suggests the devices could actually increase risk by encouraging people to spend more time on their cellphones and drive faster while doing so.

What’s more, according to a new study by NHTSA that has been reviewed by The Wall Street Journal, people spent more time on the distracting task of dialing when they use headsets and voice-activated dialing systems. The new voice-activated dialing method took nearly twice as long as punching the buttons on the phone the old-fashioned way, according to the study.

What voice-activated dialing method are they talking about? My phone has a convenient key on the side. I press it, it beeps, and I say “home” in a stentorian voice — then it phones home for me. Granted, it may take two or three times — particularly if anyone’s around — but it’s much less distracting than looking at the phone’s display.

Some of these studies mix cause and effect:

In 2001, a Norwegian study of about 9,000 drivers found that hands-free users made more calls than callers who held their phones to their ears, potentially putting drivers more at risk. Meanwhile, the Swedish National Road Administration installed cameras in 40 cars and found that drivers wearing headsets drove faster than drivers holding their phones.

Maybe people who make a lot of phone calls buy a headset? And maybe people who find it harder to drive with phone in hand drive more slowly than people with a hands-free headset.

This looks like a meaningful finding though:

Braking time slowed by as much 45% for cellphone users, with no improvement for those wearing headsets.

An interesting study:

Most recently, three Utah psychology professors — Frank Drews, Monisha Pasupathi and Dr. Strayer — put 48 adults behind the wheel of a driving simulator. They found drivers talking on the phone with headsets missed four times as many exits as drivers talking to another passenger. The study notes that a fellow passenger “collaborates in the task of driving safely by referring to traffic and conversing about it … something that a person on the other end of a cellphone cannot do.”

When Microsoft finally researched how their customers used Excel, they learned that they rarely used it as a spreadsheet; they used it primarily as a database (of sorts). Geneticists have been using Excel to process the massive amounts of data coming out of microarrays — but Excel wasn’t designed for that. From Excel ate my DNA:

Excel is widely used in genetic research to process microarray data. A microarray chip detects amounts of protein produced from thousands of different genes, enabling researchers to see which particular gene is being expressed in a sample of diseased tissue, for example.

The errors are introduced because some genetic identifiers look very like dates to Excel. If the spreadsheet is not properly set up, it will convert an identifier, such as SEPT2 to a date: 2-Sep. The conversion, the researchers say, is irreversible: once the error has been introduced, the original data is gone.

(Hat tip to Boing Boing.)

NPR : Status of Women in Iraq, Part II: Villages surprised me by noting that Oprah is the most popular television show in rural Iraq:

Women in Iraq’s cities have made strides in education and civil rights since the fall of Saddam Hussein. But rural women still struggle with illiteracy, poverty and confining traditions. They rarely leave their villages. Now the outside world is creeping into their lives via satellite TV. But shows like Oprah ? a favorite ? also underscore the problems facing rural women and the paucity of solutions to those problems.

One of the women interviewed (via interpreter) mentioned how she loved the stories about people surviving terrible medical conditions ? people in Iraq don’t get cured like that, she noted.

The other night, I caught NPR : The Industrious Nature of ‘Bolero’:

Bolero started out as a ballet score commissioned by dancer Ida Rubenstein. Her troupe danced the composition’s first performance at the Paris Opera in 1928. It was an instant hit.

Ravel, whose roots were in the Basque country on the French-Spanish border, originally called the piece Fandango. As romantic as it may seem, Ravel said the pulsing, rhythmic composition was inspired by one of the factories he had visited with his father, who was an engineer.

“It’s the orchestra that makes it work,” Hoffman says. “It’s the colors in the orchestra. He keeps adding instruments, he keeps changing the orchestration. But he doesn’t change the tune, he doesn’t change the harmony, he doesn’t change the rhythm. Nothing changes except the orchestration — and the volume.”

The radio show cited an amusingly named CD compilation of nothing but Bolero variants: Ravel’s Greatest Hit: The Ultimate Bolero. (Note the singular Hit.)