Rosenqvist & Skans use European Tour data from the past decade to measure the impact of confidence on performance. Because of the existence of the cut in most tournaments and the natural division of the field into successes and failures by the cut, it’s possible to look at how making or missing the cut affects performance in the subsequent tournament. Players who make or miss the cut are separated by very small differences in performance (as little as a single stroke for those directly on either side of the cut line) and are also nearly identical in terms of long-term talent. That means we should expect their performances to be similar in subsequent weeks – assuming that there isn’t any impact from prior weeks. What Rosenqvist & Skans find is that there is a difference in performance between those who barely made the cut and those who barely missed the cut (they create these groups using players within six strokes of the cut in either direction, though they also compared smaller ranges). Players who just made the cut in the treatment tournament are ~3% more likely to make it in the outcome tournament. Players who make the cut also play ~0.125 strokes better per round in the first two rounds of the following tournament. The authors explain this outcome as a product of enhanced or diminished confidence effecting the players’s performance. - golfanalytics.wordpress.com