As any experienced turker will tell you, recovering from a bad HIT approval rate can be a frustrating experience. It seems to take forever to come back from the damage that just one or two MTurk HIT rejections can do and all the time your HIT approval rate is damaged, your ability to make money online is compromised.
If you are new to turking and aren’t aware, Amazon Mechanical Turk calculates your HIT approval rate by comparing how many of your MTurk HITS have been rejected by requesters for HITs submitted against how many have been accepted. The resulting percentages are called your HIT rejection rate and your HIT approval rate. (All these figures can be seen on the Dashboard part of your Mechanical Turk account.)
The problem is that many of the requesters insist on a HIT approval rate of 95% or better as a qualification requirement and if you don’t meet the qualification standard, they don’t allow you do their HITs. These MTurk HITS are very often some of the best paid ones and so getting a bad HIT approval rate can really damage your ability to make money online.
As I have mentioned before, when I started out with Mechanical Turk, I didn’t appreciate the problems that having a bad HIT approval rate might bring, so I just tried out lots of different HITs without really caring too much whether some of them got rejected or not. This came back to haunt me and I learnt my lesson accordingly.
More recently, however, I have seen my HIT approval rate drop again through no fault of my own. This was apparently because, as I found out from turkers at TurkopticonToolbar, a requester who had been reliable in the past suddenly started using new (faulty) software which was wrongly automatically rejecting HITs that were actually completely fine. I did complain about it, of course, but it was to no avail, as usually happens! (See 10 reasons why I hate Mechanical Turk)
Anyway, I’ve spent my time recently working my socks off on getting my HIT approval rating back up to 95%. It isn’t fun. As well as my choice of HITs being reduced, each time I do a new HIT I am worried about getting another rejection and getting pushed back down again (once bitten, twice shy!).
I’m not sure if I mentioned it in my comparison of MTurk and Microworkers: MTurk or Microworkers, which is best?, but Microworkers are more generous with when it comes to recovering from a bad HIT approval rate. With Microworkers your rate will recover naturally with time, even if you don’t do anything - so long as you don’t keep picking up rejections you will be okay.
In conclusion, my advice would be to not let your MTurk HIT approval rate fall below 95% if you can possibly help it. If it does happen, I would focus on getting it back up by doing ‘safe’ HITs, that’s to say HITs being offered by MTurk requesters that you trust, as you can’t afford to get any more rejections. Be prepared for a long haul, though - because the HIT approval rate is a proportional figure, you will need many new HIT approvals to make up for just a few rejections.