ReCAPTCHA

Humans Are Computers, Too!

The image you see to the right is an example of reCAPTCHA (revision of Completely Automated Public Turing test to tell Computers and Humans Apart).

reCAPTCHA is a digital tool used to deter automated form-filling and exploitation of web-based registration systems. Computer programs (bots) sometimes traverse the Internet to try and complete these forms quickly to generate false reviews, spam message boards with links, or generate pay-per-click revenue. However, computers have trouble translating those distorted images of text to actual text, while it is (relatively) simple for humans to do so. reCAPTCHA exploits this difference to check if form fillers are likely human.

The inventor of reCAPTCHA, a computer scientist named Luis von Ahn, noted that the computer’s difficulty deciphering text is also a roadblock to progress in a different arena—the scanning, recording, and cataloging of pre-digital era books. He decided to crowdsource some human computers to help out. Look at this example to see how he applied reCAPTCHA to the scanning of books:

By simply altering the origin of the problematic data (fuzzy text) from computer-generated images to alphanumeric text typed by human beings, the reCAPTCHA problem becomes doubly useful. Not only are you demonstrating your humanity to the system, you are also utilizing your human computing skills to help digitize the world’s books for generations to come. Good for you!

What Is Human Computation?

The word compute means to calculate or reckon, meaning a computer is simply something that calculates or reckons information. Humans have been computers for thousands of years; evidence of counting dates back to 30,000 B.C.E. Only in the past century have we defined computer as a digital/mechanical device that calculates for us.

Most of the time, digital computers work for humans. However, sometimes humans work for digital computers to help with tasks that digital computers are not currently capable of performing. A technique known as human-based computation leverages the ability of humans to process certain types of information more efficiently than machines by outsourcing certain tasks to humans. Together, man and machine are able to solve complex tasks faster and more economically than either could do on their own.

Some tasks that humans can perform remarkably well through specialized brain/neural functions are not well-suited to digital computers (yet!). For example, humans are much better at face recognition and language translation (though state-of-the-art algorithms are becoming more competitive all the time). On the other hand, computers exceed the capabilities of humans in rote data collection, organization, and in some cases, interpretation. As such, human-based computation leverages the abilities of both humans and computers to complete complex tasks. The analysis of tasks performed well or quickly by humans is accelerated or automated by computers, and vice versa.

A great example of human computation is the use of reCAPTCHA to digitize physical texts, but it’s not the only one. For instance, Luis von Ahn has also developed Duolingo, an digital tool to translate the World Wide Web into different languages by leveraging human computation and translation skills as a language learning opportunity for those who participate. Watch the following TEDx talk in which Luis explains how human computation is leveraged with both reCAPTCHA and Duolingo:

https://www.youtube.com/embed/cQl6jUjFjp4

Not all crowdsourcing efforts are entirely “noble.” Many simply want to leverage human computing on a large scale to accomplish tasks that may be more difficult for a small amount of disconnected people to complete today. Listed below are few of these very popular crowdsourcing efforts online today. How might they inspire your own crowdsourcing efforts?

  • Mechanical Turk: “We give businesses and developers access to an on-demand, scalable workforce. Workers select from thousands of tasks and work whenever it’s convenient.”
  • Kickstarter: “Kickstarter is the world’s largest funding platform for creative projects. Every week, tens of thousands of amazing people pledge millions of dollars to projects from the worlds of music, film, art, technology, design, food, publishing and other creative fields.”
  • Fold.it: “Foldit is a revolutionary new computer game enabling you to contribute to important scientific research.”