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Why oDesk Has No Spammers
© Image: Panos Ipeirotis

Why oDesk Has No Spammers

Editor's Note: The following is a guest post from one of our contributing experts, Panos Ipeirotis, an Associate Professor and George A. Kellner Faculty Fellow at the Department of Information, Operations, and Management Sciences at Leonard N. Stern School of Business of New York University. This post appeared originally on his blog and is re-posted here with permission.

So, in my last blog post, I described a brief outline on how to use oDesk to execute automatically a set of tasks, in a "Mechanical Turk" style (i.e., no interviews for hiring and completely computer-mediated process for posting a job, hiring, and ending a contract).

A legitimate question by appeared in the comments:

"Well, the concept is certainly interesting. But is there a compelling reason to do microstasks on oDesk? Is it because oDesk has a rating system?"

So, here is my answer: If you hire contractors on oDesk you will not run into any spammers, even without any quality control. Why is that? Is there a magic ingredient at oDesk? Short answer: Yes, there is an ingredient: Lack of anonymity!

It is a very well-known fact that if a marketplace allows anonymous participants and cheap generation of new identities, the marketplace is going to fall victim to malicious participants. There are many examples of markets that allowed anonymity and each generation of pseudonyms, that ultimately became "market for lemons." Unfortunately, when you have cheap identity generation, the reputation system of the marketplace becomes extremely easy to manipulate.

So, what is different with oDesk? oDesk has contractors that are not anonymous and their userids are tied (strongly) to a real world identity (onymous?). For example, to withdraw money from oDesk into a bank account, the name in the bank account needs to match the name that listed on oDesk. There are other mechanisms as well for verifying the identify of the contractors (e.g., when I listed myself as a contractor, I had to upload copies of my driving license, copies of my bank statements, etc), but the details of the implementation do not matter. The key element is to make it difficult or costly to create new or false identities.

A strong identity verification pretty much eliminates any type of spam. Why? Because the spammers cannot simply shut down their account after being caught spamming and create a new one. Therefore, all the oDesk contractors with 99.9% probability will not try to spam you. Now, do not get me wrong: you are going to run into incompetent contractors. But there is a difference between an incompetent contractor and one that deliberately tries to spam you.

As my colleague John Horton says: "An incompetent worker who puts some effort in the task is like a bad bus driver: Very slow to take you to your destination but at least you are going towards the correct place, albeit slowly. The spammers are like the unlicensed cab drivers that take you to a random place in order to demand arbitrary fare amounts afterwards to take you to your correct destination."

- Panos Ipeirotis is an Associate Professor and George A. Kellner Faculty Fellow at the Department of Information, Operations, and Management Sciences at Leonard N. Stern School of Business of New York University. He is also the Chief Scientist at Tagasauris, and in 2012-2013 serves as “academic-in-residence” at oDesk Research. His recent research interests focus on crowdsourcing and on mining user-generated content on the Internet. He received his Ph.D. degree in Computer Science from Columbia University in 2004, working with Prof. Luis Gravano. He has received three “Best Paper” awards (IEEE ICDE 2005, ACM SIGMOD 2006, WWW 2011), two “Best Paper Runner Up” awards (JCDL 2002, ACM KDD 2008), and is also a recipient of a CAREER award from the National Science Foundation and several other industry grants. In his spare time, he writes about crowdsourcing and various other topics on his blog, “A Computer Scientist in a Business School,” an activity that seems to generate more interest and recognition than any of the above.

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  • Seth W Seth W Oct 29, 2012 12:17 am GMT

    Bravo, could not agree more. This is your work we're talking about; there has to be some accountability! Ziptask does a huge portion of its hiring from oDesk for this exact reason.

  • Mark Sears Mark Sears Nov 01, 2012 01:22 am GMT

    Accountability in a workforce is 100% required to get good results. Lots of layers or technology on top of a faceless crowd will not lead to quality results, just like a top chef with a great recipe can't bake a great cake with stale flour and rotten eggs ;-)

    This is fundamental to how CloudFactory is building up our workforce and it is leading to great results for early clients doing microtask work similar to Mechanical Turk.

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