A Comparison of Methods to Assess Putting Green Trueness.

Because there was not a standard method to measure putting green surface trueness, a study was done to compare three methods for measuring putting green trueness.  The Royal & Ancient “Holing Out Test” (HOT), a visual bobble test, and a ball spread test were conducted in 2013 on 150 greens from 50 golf courses in New Zealand.  A ball rolling ramp (Greenstester.com) was used to roll balls for each method.  For the HOT, the number of balls out of 10 rolled from a fixed location that entered a golf hole about 2.5 meters away were counted.  The spread test measured dispersion of the stopping positions of a group of balls rolled approximately 2.5 meters from a fixed location.  The bobble test was a visual rating from 1 to 10 of the amount of bobbling and snaking of balls while rolling 2.5 meters.  Ball exiting and tracking issues with the Greenstester ramp led to the HOT and spread test being more subjective than expected and more difficult to administer than the bobble test.  Weak correlations (r = 0.02 to 0.40) and a large difference in sensitivity between the HOT and bobble test were proof that the methods were not measuring the same thing.  For many greens, rolled balls visually bobbled and snaked, however, most balls rolled for the HOT went in the hole.  The HOT provides evidence that despite the appearance of the putting surface and how the ball visually rolls, balls can still be holed when hit on the proper line with the correct speed.