Amazon Mechanical Turk

The Amazon Mechanical Turk (MTurk) is one of the suite of Amazon Web Services, a crowdsourcing marketplace that enables computer programs to co-ordinate the use of human intelligence to perform tasks which computers are unable to do. Requesters, the human beings that write these programs, are able to pose tasks known as HITs (Human Intelligence Tasks), such as choosing the best among several photographs of a storefront, writing product descriptions, or identifying performers on music CDs. Workers (called Providers in Mechanical Turk's Terms of Service) can then browse among existing tasks and complete them for a monetary payment set by the Requester. To place HITs, the requesting programs use an open Application Programming Interface, or the more limited Mturk Requester site.

Requesters can ask that Workers fulfill Qualifications before engaging a task, and they can set up a test in order to verify the Qualification. They can also accept or reject the result sent by the Worker, which reflects on the Worker's reputation. Currently, a Requester has to have a U.S. address, but Workers can be anywhere in the world. Payments for completing tasks can be redeemed on Amazon.com via gift certificate or be later transferred to a Worker's U.S. bank account. Requesters, which are typically corporations, pay 10 percent over the price of successfully completed HITs (or more for extremely cheap HITs) to Amazon.

Name

The name Mechanical Turk comes from "The Turk", a chess-playing automaton of the 18th century, which was made by Wolfgang von Kempelen. It toured Europe beating the likes of Napoleon Bonaparte and Benjamin Franklin. It was later revealed that this "machine" was not an automaton at all but was in fact a chess master hidden in a special compartment controlling its operations. Likewise, the Mechanical Turk web service allows humans to help the machines of today to perform tasks they aren't suited for.

History, HIT types, and user demographics

The service was initially invented for Amazon's in-house use by Peter Cohen, to find duplicates among its web pages describing products.

The service was launched publicly on November 2, 2005 and, as of 2009, is still in beta. Following its launch, the Mechanical Turk user base grew quickly, in part the result of the Slashdot effect. At that time, there were a huge number of "Human Intelligence Tasks" (HITs) in the system. In early- to mid-November 2005, there were tens of thousands of HITs, all of them uploaded to the system by Amazon itself for some of its internal tasks that required human intelligence. Most of these were related to music CD items. Web traffic grew to a massive amount near the beginning of December.

However, the number of HITs in the system soon decreased, and by December 20, there were less than 100 groups of HITs on the average page load. In January, new types of HITs were set up, such as top three lists ranking for the (now defunct) Amazon Unspun site, and third-party HITs began to appear as well. By April 2006, there were only the occasional batch of 25 HIT groups being offered, and the service had slowed to a crawl.

As of January 2007, there were new HITs being offered of podcast transcribing and rating and image tagging. The transcription HITs, mostly offered by Casting Words [1], are still posted regularly as of March 2009. Other common HIT types ask Turkers to write or rewrite sentences, paragraphs, or whole articles. These have rewards ranging from one cent to about $10. HITs which reward people for linking to or commenting on a blog, or friending a person on Facebook are also often encountered, as are surveys.

In March 2007, there were reportedly more than 100,000 workers in over 100 countries.

According to a survey conducted through one MTurk HIT, Turkers are primarily located in the United States with demographics generally similar to the overall Internet population in the US.. However, workers on Mechanical Turk are typically younger than the average Internet user, and (correspondingly?) are poorer, tend to be single, and have smaller families. There is also a significantly higher number of females.

Searches

In 2007, the service began to be used to search for prominent missing individuals. It was first suggested during the search for James Kim, but his body was found before any technical progress was made. That summer, computer scientist Jim Gray disappeared on his yacht and Amazon's Werner Vogels, a personal friend, made arrangements for DigitalGlobe, which provides satellite data for Google Maps and Google Earth, to put recent photography of the Farallon Islands on the Mechanical Turk. A front-page story on Digg attracted 12,000 searchers who worked with imaging professionals on the same data. The search was unsuccessful. In September 2007, a similar arrangement was repeated in the search for aviator Steve Fossett. Satellite data was divided into 85 squared meter sections, and Mechanical Turk users were asked to flag images with "foreign objects" that might be a crash site or other evidence that should be examined more closely.[2] The search was also unsuccessful, the crash site was eventually found by hikers about a year later.

Third-party programming

Programmers have developed various browser extensions and scripts designed to simplify the process of completing HITs. According to the Amazon Web Services Blog, however, Amazon appears to disapprove of the ones that automate the process 100% and take out the human element. Accounts using so-called automated bots have been banned.

API

Amazon makes available an API to give users another access point to the MTurk system. The MTurk API lets a programmer submit HITs to MTurk, retrieve completed work, and approve/deny that work. Web sites and Web services can use the API to integrate MTurk work into other web applications, providing users with alternatives to the interface Amazon has built for these functions.

Related systems

Main article: Crowdsourcing

MTurk is comparable in some respects to the now discontinued Google Answers service. However, the mechanical Turk is a more general marketplace that can potentially help distribute any kind of work tasks all over the world. The Collaborative Human Interpreter (CHI) by Philipp Lenssen also suggested using distributed human intelligence to help computer programs perform tasks that computers cannot do well. MTurk could be used as the execution engine for the CHI.

Criticism

Because HITs are typically simple, repetitive tasks and users are paid often only a few cents to complete them, some have criticized Mechanical Turk as a "virtual sweatshop." Because workers are paid as contractors rather than employees, requesters do not have to file forms for, nor to pay, payroll taxes, and they avoid laws regarding minimum wage, overtime, and workers compensation. Workers, though, must report their income as self-employment income. In addition, some requesters have taken advantage of workers by having them do the tasks, then rejecting their submission in order to avoid paying. However, at least some workers on Mechanical Turk are people who are middle class and do the work for fun.

Also, Amazon does not monitor the service and refers all complaints to the poster of the HIT. This hands-off approach can be seen as a prime cause of the actions evident in many of the complaints above.

External links

• Official website
• Turker Nation A forum created by workers to discuss requesters, HITs, and MTurk in general
• Wired Magazine story about 'Crowdsourcing' June, 2006
• Business Week Article on Mechanical Turk
• New York Times Article on Mechanical Turk
• Salon.com Article on Mechanical Turk
• Intro to Amazon's Mechanical Turk