How humans help computers compute and help Amazon build a new business

Artificial Intelligence, With Help From the Humans – by JASON PONTIN/NY Times

COMPUTERS still do some things very poorly. Even when they pool their memory and processors in powerful networks, they remain unevenly intelligent. Things that humans do with little conscious thought, such as recognizing patterns or meanings in images, language or concepts, only baffle the machines.

These lacunae in computers’ abilities would be of interest only to computer scientists, except that many individuals and companies are finding it harder to locate and organize the swelling mass of information that our digital civilization creates.

The problem has prompted a spooky, but elegant, business idea: why not use the Web to create marketplaces of willing human beings who will perform the tasks that computers cannot? Jeff Bezos , the chief executive of Amazon.com , has created Amazon Mechanical Turk, an online service involving human workers, and he has also personally invested in a human-assisted search company called ChaCha . Mr. Bezos describes the phenomenon very prettily, calling it “artificial artificial intelligence.”

“Normally, a human makes a request of a computer, and the computer does the computation of the task,” he said. “But artificial artificial intelligences like Mechanical Turk invert all that. The computer has a task that is easy for a human but extraordinarily hard for the computer. So instead of calling a computer service to perform the function, it calls a human.”

Mechanical Turk began life as a service that Amazon itself needed. (The name recalls a famous 18th-century hoax, where what seemed to be a chess-playing automaton really concealed a human chess master.) Amazon had millions of Web pages that described individual products, but it wanted to weed out the duplicate pages. Software could help, but algorithmically eliminating all the duplicates was impossible, according to Mr. Bezos. So the company began to develop a Web site where people would look at product pages and be paid a few cents for every duplicate page they correctly identified.

Mr. Bezos figured that what had been useful to Amazon would be valuable to other businesses, too. The company opened Mechanical Turk as a public site in November 2005. Today, there are more than 100,000 “Turk Workers” in more than 100 countries who earn micropayments in exchange for completing a wide range of quick tasks called HITs, for human intelligence tasks, for various companies.

PriceGrabber.com ,a comparison shopping site, uses Mechanical Turk to match images to the product pages. “Harnessing the power of this enormous, decentralized work force allows us to obtain images for a wide variety of items in a fraction of the time it would have taken to do it ourselves,” said Sagar M. Jethani, PriceGrabber’s director of content development and community.

Mechanical Turk’s customers are corporations. By contrast, ChaCha.com , a start-up in Carmel, Ind., uses artificial artificial intelligence — sometimes also called crowdsourcing — to help individual computer users find better results when they search the Web. ChaCha, which began last year, pays 30,000 flesh-and-blood “guides” working from home or the local coffee shop as much as $10 an hour to direct Web surfers to the most relevant resources.

Amazon makes money from Mechanical Turk by charging companies 10 percent of the price of a successfully completed HIT. For simple HITs that cost less than 1 cent, Amazon charges half a cent. ChaCha intends to make money the way most other search companies do: by charging advertisers for contextually relevant links and advertisements.

Harnessing the collective wisdom of crowds isn’t new. It is employed by many of the “Web 2.0” social networks like Digg and Del.icio.us, which rely on human readers to select the most worthwhile items on the Web to read. But creating marketplaces of mercenary intelligences is genuinely novel.

What is it like to be an individual component of these digital, collective minds?

To find out, I experimented. After registering at www.mturk.com , I was confronted with a table of HITs that I could perform, together with the price that I would be paid. I first accepted a job from ContentSpooling.net that asked me to write three titles for an article about annuities and their use in retirement planning. Then I viewed a series of images apparently captured from a vehicle moving through the gray suburbs of North London, and, at the request of Geospatial Vision, a division of the British technology company Oxford Metrics Group, identified objects like road signs and markings.

For all this, my Amazon account was credited the lordly sum of 12 cents. The entire experience lasted no more than 15 minutes, and from my point of view, as an occluded part of the hive-mind, it made no sense at all.

I was also interested in learning what it was like to be a consumer of crowdsourcing. So at 2:40 p.m. on March 14, I asked ChaCha, “Who was Evelyn Waugh’s commanding officer in the Commandos during World War II?” In an instant-messaging window, CandieSue22087 immediately welcomed me to ChaCha and asked me to be patient.

At 2:44, CandieSue threw up her virtual hands and transferred me to another guide, Tressie57635, who referred me to an academic paper on “suffixal sound symbolism in the novels of Evelyn Waugh.” When I protested, Tressie complained that it was a hard search, and at 2:49 she gave up, typing that I might do better with yet another guide. When I agreed, Tressie accidentally ended the search altogether — but not before serving me a page of 12 search results, not one of which was relevant.

A quick search on Google quickly provided the right answer.

THERE have been two common objections to artificial artificial intelligence. The first, confirmed by my own experiences searching on ChaCha, is that the networks are no more intelligent than their smartest members. Katharine Mieszkowski, writing last year on Salon.com , raised the second, more serious criticism. She saw Mechanical Turk as a kind of virtual sweatshop. “There is something a little disturbing about a billionaire like Bezos dreaming up new ways to get ordinary folk to do work for him for pennies,” she wrote.

The ever-genial Mr. Bezos dismisses the criticism. “MTurk is a marketplace where folks who have work meet up with folks who want to do work,” he said.

Why do people become Turk Workers and ChaCha Guides? In poor countries, the money earned could offer a significant contribution to a family’s wealth. But even Mr. Bezos concedes that Turk Workers from rich countries probably can’t live on the small sums involved. “The people I’ve seen commenting on blogs seem mostly to be using MTurk as a supplemental form of income,” he said.

Mitch Fernandez, 38, a disabled former United States Army linguist, said by e-mail that he became a Turk Worker for various reasons: “At first, I was just curious about the idea of crowdsourcing.” But he said he soon found that by working about two hours a day, he could often earn more than $100 a week. In the last nine months he made around $4,000, which he used to buy a high-definition television, a DVD player and a new subwoofer — all from Amazon.com .

“I do this primarily for the money, but I also view it as a form of therapy to get me used to working again.” he explained. “The experience has gotten me thinking about pursuing a library science degree.”

We probably have at least another 25 years before computers are more powerful than human brains, according to the most optimistic artificial intelligence experts. Until then, people will be able to sell their idle brains to the companies and people who need the special processing power that they alone possess through marketplaces like Mechanical Turk and ChaCha.

(Jason Pontin is the editor in chief and publisher of Technology Review, a magazine and Web site owned by M.I.T. E-mail:
pontin@nytimes.com)