Survey incentives

Question

Not sure if UX is the right place for this, but it is partly a behavioral economics question so I hope I'm in a reasonable place.

For a survey prize draw, has there been any research done to assess whether, everything else being equal, a better response will be achieved with either a small number of high-value prizes, or a larger number of lower-value incentives? For example, if I have a £150 research budget, does it make more sense for me to offer than as

• 1 of 5 £30 Amazon vouchers
• 1 of 3 £50 Amazon vouchers

Answer 1

Great question! I recently attended a masterclass on The Power of Persuasion of Robert Cialdini. One of the most powerful principles is the Reciprocation principle.

By giving a gift before asking something of someone, they in most cases feel obligated to help you.

The example used in by Robert Cialdini on the website is as followed:

One of the best demonstrations of the Principle of Reciprocity comes from a series of studies conducted in restaurants. So the last time you visited a restaurant, there’s a good chance that the waiter or waitress will have given you a gift. Probably about the same time that they bring your bill. A liqueur, perhaps, or a fortune cookie, or perhaps a simple mint.

So here’s the question. Does the giving of a mint have any influence over how much tip you’re going to leave them? Most people will say no. But that mint can make a surprising difference. In the study, giving diners a single mint at the end of their meal typically increased tips by around 3%.

Interestingly, if the gift is doubled and two mints are provided, tips don’t double. They quadruple—a 14% increase in tips. But perhaps most interesting of all is the fact that if the waiter provides one mint, starts to walk away from the table, but pauses, turns back and says, “For you nice people, here’s an extra mint,” tips go through the roof. A 23% increase, influenced not by what was given, but how it was given.

During the masterclass there was a different example given, sending a survey to CEO's. I don't have acces to the slides but I remember it as followed (there might be some errors in the actual percentages etc)

In one case they promised a reward after the survey was filled in (I believe 20$), in the other variant they gave the CEO a gift. A $5 voucher they could use however they liked, they could also not fill in the survey and still use the $5 voucher.

Surprisingly the variant had with giving the gift of 5$ first and asking someone to fill in had a much higher response rate. Version A where they got the reward after the survey had a 5% response rate. Version B had a response rate of 20%.

To sum it up, I think neither of your rewards will get the highest response rate (percentage wise). I believe that if you give out 30x 5$ to everyone you email you will get the highest response rate (percentage wise) but if you send the survey to 10.000 users you probably will get more responses by offering a reward.

If you wish to hook the most users, I would re-frame the reward. Instead of saying you get a chance on 1 of the 5 giftcards. You could change it to 'have a chance to receive a gift card of 5$ to 100$.' This is because the 'unknown' part in the reward gives more dopamine to users (that is why gambling is so addictive, the 'unknown possible reward' generates the most dopamine.')

Answer 2

Amount of effort participants will put in (quality of responses) will be proportional to the value of the prize. Hence, the higher the prize the more will participants be incentivized.

So if you are only measuring the quality of the responses, go with 1 $150 voucher, but that will yield in a lower response (and completion) rate. Finding a good balance is key.

If you have some in depth tasks / questions in your survey, always lean towards higher value prizes. If you are conducting more basic (demographic type) research, lean toward the quantity of prizes.

Answer 3

Basically, surveys are meant to gather higher volume of data which means greater number of participants as you can validate the data by data analysis. It is more towards quantitative methods. This being said, it depends on the type of questions you ask. If the survey has a lot of close-ended questions then its most likely lan towards quantitative analysis. However, if the survey has lot of open-ended questions then it is leaning more towards Qualitative analysis where you will have to look for emerging themes and patterns. If your budget is $150, then I will divide the gift voucher based on the type of questions (open Vs close), which indirectly provides if you are leaning towards Quant or Qualitative methods. Distribute the money accordingly.