|David Warner - photo courtesy of Flickr user Paddynapper|
He has a phenomenally high activity rate in test matches. (for a description of activity rate, click here) The rest of the opening batsmen in the world have a collective activity rate of 0.248 over the past 2 years. Warner has an activity rate of 0.381.
This means that he is effectively about 54% better than the average opener at finding runs in the field. This is a massive difference.
However it seems to have come at a cost. In recent matches he has been run out, and has also been involved in a run out for his partner.
It's difficult to quantify the effects of a run out. They are often worth more than a normal wicket, because they come against the normal run of play. I wrote an article about this last July in relation to One Day Internationals.
Warner has run 488 runs, with one run out (to him). The rest of the test openers in the same period have run 8808 runs with 13 run outs, or 677.5 runs per run out. (I only look at run outs for the batsman, rather than their partners, as it avoids double ups. To make the comparison fair I had to do the same with Warner.) On the face of it, it seems that Warner's approach is too risky. However there is another way to look at it.
A batsman gets out eventually, and they have a number of balls to use to score runs between dismissals. A run out is different from other dismissals in that it's not really related to the skill at hitting the ball. As a result a simple batting average isn't the best way to assess it. Instead we need to look at how a batsman uses both the resources that they have, namely their wicket and their deliveries between getting out in some other method.
The average opening innings lasts 68.7 balls, and includes slightly under 16 run runs. Warner only lasts 59.2 balls on average, but includes just over 20 run runs.
If we assume that if Warner had run between wickets like the other openers that he would not have been run out, then we can look at what his average would have been if he had been more careful with his running. Instead of 20.33 runs per innings from running, he would have got 13.24 runs per innings. He would have scored 170 less runs in his career to date. (892 rather than 1062) Also, instead of 24 dismissals, he would have only been out 23 times.
If everything else was the same, except for the running, and we assume that his innings where he was run out was a not out, his average would have dropped from the current 44.50 to 38.78.
While his running may seem risky, it is actually a big part of why he has made such a successful start to his career. As he is taking his running to the next level, his entire game is improving with it.