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Is there any app or start-up which delegates work to my social connections? Like a Mechanical Turk for my social sphere. Would be a nice solution.
Earlier quoted context omitted.
looks like there's a need for a mturk preferred worker aggregation service.
Seriously, for being a fire-and-forget API to the lowest possible level of human tasks, it requires a heck of a lot of hands on management, including arguing with identifiable people over two cents . (YOU DIDN'T SAY TO TURN OFF CAPS. I wish I were exaggerating.) I ended up writing off five hours to goodwill when I did a project with a $100 turking component for a client. To use a line favored by my old Indian colleag…
I have the ominous feeling that it will be mind numbingly boring, but nonetheless money is money.
Is there any app or start-up which delegates work to my social connections? Like a Mechanical Turk for my social sphere. Would be a nice solution.
What about a local mech turk type program for small tasks? Maybe craigslist or angieslist is filling this need?
They are tackling tasks like extremely difficult OCR and collaborative editing and proofreading.
I've used mturk at work to automate transcribing short recordings and have found that it works pretty well. The trick is to qualify your workers so that they pass some kind of test. You can also only accept workers that have a rating above some minimum. Then, critically, as suggested by others here, get each task done multiple times for cross-checking. And make sure that your instructions are clear.
I think this article doesn't reflect everyone's experience with Mechanical Turk. We get lots of high quality work out of Mechanical Turk and lots of other companies do as well. It does take a fair amount of work to get the quality right - that's how we got started as a business and that's why many people still come to us.
As an aside, if the author of the article is reading this thread and wants data, we would be happy to talk about it.
I think that your HIT design highlights several common mistakes requesters make on MTurk:
- You are underpaying for the task (would you write a good review of Berkeley, CA for $1 for a stranger?)
- You provide no aggregation or verification step, to ensure that turkers know their work should jive with other turkers' output. You also give no indication that such verification is possible or likely to happen.
- Your task output is poorly defined and open to interpretation. You may have asked a straightforward question, but I assume you placed a blank textbox on the screen and expected well-formed paragraphs in return.
If you want a great example of text synthesis of relatively high quality using MTurk for prices in the range of your budget, see http://borismus.com/crowdforge/
If you want to learn more about how to design HIT workflows, see http://projects.csail.mit.edu/soylent/ (disclosure: I share an office with and work with Michael Bernstein, but not on this work). One of Soylent's contributions was the Find-Fix-Verify design pattern, which helps with some of the problems you raise.
Your task is even harder, of course, since you require subject-matter experts in a fictional location. So perhaps MTurk is the wrong crowd for your task.
The article raises an interesting point: that many turkers just assume there is no quality assurance being done on the requester end and everything will automatically be accepted and paid for. Since it is tricky to automate QA for huge sets of tasks I would guess this assumption is mostly correct, and turkers take advantage of it.
"Tricky to automate" what? Are you not literally in the middle of using a tool that helps you automate QA for huge sets of tasks? It should be trivial to create a task, create a task for evaluating that task, and yet another task for evaluating that task. Run all three long enough and you will in fact get good results. Obviously if you're going to use an unreliable protocol there have to be management protocols in ef…
So you'd think this tool would do this for you - but instead you need another layer on top, either one you code, or some 3rd party tool like CrowdFlower.
The article raises an interesting point: that many turkers just assume there is no quality assurance being done on the requester end and everything will automatically be accepted and paid for. Since it is tricky to automate QA for huge sets of tasks I would guess this assumption is mostly correct, and turkers take advantage of it.
"Tricky to automate" what? Are you not literally in the middle of using a tool that helps you automate QA for huge sets of tasks? It should be trivial to create a task, create a task for evaluating that task, and yet another task for evaluating that task. Run all three long enough and you will in fact get good results. Obviously if you're going to use an unreliable protocol there have to be management protocols in ef…
Even if in theory, feeding back the results into Mechanical Turk for manual evaluation will correct errors, there are still huge tradeoffs in practice.
Suppose you had three people look at a task and say if it was done correctly or not. We pick the most popular choice out of the three. This works fine for tasks like speech transcription where it is easy to tell if it was done correctly or not. But what about tasks like labeling features in biological images? Surprisingly, even if you show people examples of what is correct and not correct, they still have a hard time distinguishing between the two. This are the kinds of difficult tasks that are especially in need of QA.
If the people evaluating correctness are only right 60 percent of the time, you'd better have more than 3 people vote on whether it's correct, just to get a good estimate. (Also, we are assuming people are biased toward the correct answer, rather than toward the wrong answer, or toward a fixed response) If you need a lot of people to evaluate each task, then you're paying several times more money than you were for the original tasks, and you have to write some infrastructure for feeding things back into mechanical turk.
Like you said, it will work in principle, but there are some tradeoffs.
Personally, I prefer the gold-data method and being conservative about accepting results in the first place rather than feeding them back to get fixed or labeled incorrect.
[1] www.vision.caltech.edu/publications/WelinderPerona10.pdf