2009年12月大學(xué)英語(yǔ)四級(jí)考試模擬試題(一)

　　Mechanical Turk, by contrast, is based on “crowd sourcing”, or breaking a task into lots of tiny pieces and giving it to a big group of people to complete quickly. Most of these jobs — which the site calls HITs, for human intelligence tasks — pay just a few cents. Efficient MTurkers, as they call themselves, can make more than $100 a week doing things such as finding someone’s email address or labeling images of a particular animal in a photograph.

　　Amazon says that MTurk now has 200,000 workers from 100 different countries, but it doesn’t keep track of past figures.

　　The site — named for an 18th-century stunt involving a turbaned chess-playing “machine” with an actual chess master hidden within — began as a way to help Amazon manage its product database, says Sharon Chiarella, vice president of Amazon Mechanical Turk. Amazon uses the site to help sort images and content, paying people a few cents a task. Mechanical Turk also serves a variety of companies who need Web tasks performed, especially those that require a human element. Test-prep startup Knewton Inc., for example, uses it extensively for focus-group-type tasks, as well as enlisting people to take its practice tests.

　　Keri Knutson, a mother of five from Independence, La., discovered Mechanical Turk when her eldest son was headed for college. Ms. Knutson, now 45, needed money for his tuition and fees. She took on all kinds of low-paying but easy tasks at the beginning, from finding a place to purchase a specific item to identifying the name of a street in a photograph.

　　People looking to make money online as fee-for-service experts should read the fine print. Live Person has one of the more formal payment systems, requiring users to sign up for an account before talking with an expert. Some sites, including Associated Content and Mechanical Turk, reserve the right to refuse payment if a task is not completed satisfactorily.

　　Most sites have a robust community of workers who regularly offer one another tips on which tasks pay the best. Mechanical Turk users have an independent site called Turker Nation (turkers.proboards80.com), which reviews the companies that solicit (索求) and pay for tasks so that workers can check a company’s record before taking on a task.

　　Consumers who use these sites also need to exercise caution. Relying on legal or medical advice from an unknown online source has obvious drawbacks, and the Web sites acknowledge that some users have registered complaints about the advice offered on the sites. LivePerson warns consumers to offer their financial and personal details with care.

　　For the workers on these sites, even incremental sources of income are helpful these days. Ms. Knutson now spends the majority of her time transcribing Web audio and video for clients, earning about $250 a week for 30 hours of work. She says she has seen more competition lately but is determined to keep up her weekly pace.

　　“If I didn’t have this money,” she says, “we’d be struggling to find what to eat every week.”