How is the "average number of strokes" decided for each hole?
While watching golf competitions, the majority of players are far below the par.
Shouldn't it then be adapted? If 90% of players are doing an eagle on a Par 5, why isn't it converted to a Par 3?
It should work as long as you don't try to compare from year to year if there has been a change in-between.
The par for a hole is primarily based on the length of the hole, but other factors can also affect its value; most noticeably the type of terrain and any potential obstacles (water, hills, buildings etc). Wikipedia article for Par
The USGA lays out the following guidelines for par computation;
To quote their advice on par computation;
Yardages for guidance in computing par are given below. The effective playing length of a hole for the scratch golfer determines par. (See Section 13-3b.) These yardages may not be applied arbitrarily; the configuration of the ground and the severity of the obstacles should be taken into consideration.
Authorized golf associations are empowered to adjudicate questions of hole par. (See Decision 16/1.)
I worked on a golf app many years ago that helped map out courses in the midwest region and offer golfers help on the course - and for them to see the holes on their phone.
We had TONS of statistical data available to us and actually had a pro that was also a stats major and he found some really interesting things.
length of the hole is not a great indicator for difficulty. There was very little correlation.
most courses (not all) based their par based on what someone who shoots 75-80 would average on that hole. If a hole had a lake to shoot over for example, you could have a par 4 that was 265 that averaged 4.9 because there was such a severe penalty for going in the water. Same for bunkers, tight fairways, lots of trees and so on. Probably the reason that you see so many pros do well compared to par on some courses is because they have the ability to hit over the obstacles or not bad enough to hit into them. If joe average players that averages a 78 and loses 4 strokes per 18 because of these things, that is quite an advantage on par for the pro golfer.
"pro" courses will usually rate their courses based on a scratch golfer.
par ratings mean almost nothing. We got data on over 1000 golf courses and the average scores ranged from 79-84. If you can shoot a 75 on one course consistently but only an 81 on another, it probably has more to do with the first course having easier holes than your performance there.
the two most heavily correlated factors that we had for a holes difficulty (par rating) was the size of the green and the slope of the green. It wasn't even close. You could probably create a par 5 that was at 180 yards with a 15 foot green that had a 30 degree slope and it might average well over 5.
courses want to have 18 holes work out to 70-72. If they have a course estimated out at 67 they can try to make some holes harder or just bump up three holes. There is nothing governing this.
some courses cater to good scores to drive business. I always play a local course once a year that sucks but is really easy just so I can see the 80s.
Note: I am just a guy that saw a lot of data. I am sure someone with more golf knowledge could clarify how they deduce holes at nice courses. I am sure it has just as much to do with marketing as it does with taking statistical analysis.
