If you are facing your nemesis hole in a weekend round of golf, instead of telling yourself it is easy, you may in fact be better off telling yourself it is hard, scientists have found.Researchers at Denver University studied professional courses where a single hole had been rated as both a par five or a par four in different tournaments – meaning the player was expected to play either five strokes on the hole, or four strokes respectively.The study found that professional players performed better on the hole when it was rated as a par four than when it was rated as a par five. Bizarrely that appears to show that players presented with what appears to be a harder hole – a par 4 – perform at a higher level than when exactly the same hole is labelled a par 5, and should in theory be easier. Want the best of The Telegraph direct to your email and WhatsApp? Sign up to our free twice-daily Front Page newsletter and new audio briefings. Behavioural scientists Ryan Elmore and Andrew Urbaczewski, of Denver’s Daniels College of Business, said: “It is immediately obvious that more threes and fours are recorded when holes are rated as par 4s rather than as a par 5. “On the other hand, more fives and sixes are observed when holes are rated as a par 5 than when the same hole was rated a par 4.” They said their findings were a demonstration of loss aversion theory in action. Translated on to the fairways and greens of the golf course that means that if a player goes over par by taking five strokes on what should be a four-stroke hole they would feel worse than if they used five strokes on a par five, thereby meeting their expectation and maintaining their score. The researchers said that, according to the loss-aversion theory, they fear coming over par on the “easier” par 5 hole more than on the “harder” par 4, so play more conservatively on the par five to avoid the greater sense of loss.Mr Elmore and Mr Urbaczewski examined the scores at a number of holes at Pebble Beach – where the US Open is to be held next month – and Oakmont in the US where the par was changed from five to four to maintain the course’s difficulty in the face of improved equipment design.That gave the researchers the opportunity to examine how players approached these holes to see if the outcome chimed with loss aversion theory. The researchers’ hypothesis was that when the hole was par four professional golfers would tend to take fewer strokes than when that same hole was par five. Hideki Matsuyama, of Japan, hits from a sand trap on the 11th hole during the first round of the Wells Fargo Championship golf tournament at Quail Hollow Club in Charlotte, N.C. on May 2Credit:Chuck Burton/AP In their paper Loss Aversion in Professional Golf the pair state: “We estimate that a professional golfer will score (on average) between 0.010 and 0.187 strokes lower when Pebble Beach hole number two is labelled as a par 4 versus when the hole is labelled a par 5 in US Opens. A very similar interpretation holds for par labelling of hole number nine at Oakmont during US Opens.“The total effect over four rounds is potentially as much as a full stroke, often the difference between first and second place in a professional tournament.” Has someone told Tiger?