These researchers found, in each study (all are randomized experiments with control and treatment conditions), that a simple expression of thanks by someone in authority led people to be more likely to volunteer to do extra work. Their research shows that this happens because the simple act of being thanked makes be feel more valued — and in some of these studies — it also increased peoples' feelings of self-efficacy (essentially, the perception that they were making a bigger impact on the world around them).
…The simple act of having a boss come by and offer a public thanks to one group, and but not the other, really packed a wallop. These fundraisers were paid a fixed salary, so Grant and Gino compared the number of phone calls made be each fundraiser before and after the “thank you” intervention. The results were pretty impressive, as while there was no change in the average number of calls made by the group that was not offered thanks, the folks who heard a warm two sentence thank you from a boss made an average of about 50% more calls during the subsequent week.
Interested in reading more? See Bob's original post. <