It is said that he who controls the big data will control the future, and the race to collect and analyze massive volumes of data is on – and tennis is no exception. Technological advances provide us with all sort of statistical information unavailable in the past, and it is our job as coaches to use this data to make our practices more effective. However, this is not always as straightforward as it seems.
Let’s look at a couple of theoretical and not so theoretical examples of data and try to interpret it:
Example 1. One of the most talked about statistics now days is that most points in tennis last between 1 and 4 shots including serve and return.
a) We should spend most of our practices working on the first 4 shots.
b) We should spend our practices working mostly on the serve because aces and un-returnable serves is what ultimately shortens the points.
c) We should make sure that our young players can hit many quality shots in a row because that is the only way that they will eventually be able to hit with enough power and precision to finish the points quickly.
d) We should practice like we have always practiced – doing a bit of everything. After all the pros that are finishing the points in four shots did not scheduled their practices around the first four shots because that was not a “thing” back then.
Example 2. A 15 year analysis of Wimbledon offered us the following statistic about points won on the Men’s side: from the baseline 46%, approaching the net 64% and Serve and Volley 68%.
a) Everybody should approach the net more and serve and volley more.
b) Since there is a better chance of winning the points at the net we should spend our practice time working more around the net than on groundstrokes.
c) Players serve and volleys so seldom these days that when they do it they catch the opponent by surprise and that increase their chances of winning the point. Therefore, we should mainly work on groundstrokes but tell our students to serve and volley occasionally.
d) Professional players only approach the net when they are in total control of the point and that is why they win most of those points. Therefore, when it comes to volleying, knowing when to approach is a more important skill than the technical execution of the shot and that is what we should focus on.
The correct interpretation is somewhere in there….or not.
Having access to more information is nice, but when it comes to statistics, it is important to keep Aaron Levenstein’s quote in mind: "Statistics are like a bikini: What they reveal is suggestive, but what they conceal is vital.”