We heard from Dr. S., asking how to do a partial payment? Dr. S and her team want a specific population (people who are above a certain age and consume a certain product on a regular basis) and want to use a screening survey to screen people in and out of the survey. Dr. S, who is a good person, wants to pay the people who are screened out for their time.
I can think of two ways to do this:
1. Pay everyone the ‘base’ amount and give a bonus to people who meet the criteria.
With this way, you’d post the hit with the payment for the screamingly ONLY (maybe .05 or so) and then promise that people who passed the screener and completed the entire survey would get a bonus (say of .25). After all the responses are in, you can go back into MTurk and give everyone who did the whole survey the bonus. You’d have to separate out the people who did the whole survey from those who are screened out, which you can probably assess via the time spent (or else match worker IDs collected via Qualtrics to worker IDs in the researcher management section). This could be a bit time consuming.
The downside to this is that many workers who will qualify for the survey may shy away from a survey that promises a bonus, as many people who do promise that do not follow through. That has the potential of screwing up your ultimate purpose—figuring out whether the population of interest differs from the gen pop.
2. Screen people out and invite the people screened out to an invitation only HIT to get paid.
With this way, you’d post the hit for the whole survey payment (.30) but then screen people out based on them not being in the population of interest. You would set up the ‘sorry you don’t qualify’ screen on Qualtrics with a request for their Mturk ID and a promise that they would be invited to an invitation only HIT to get paid for the screening test. To set up an invitation only HIT, look at this blog post BUT ONLY POINTS 3, 4 AND 5.
Then you invite people, they accept it and put in their ID again (or whatever task you want them to do that takes 1 second) and then pay them.
Do our readers know any other methods?