Coaches Corner

I recently ran an idea by a professional sports mathematician, and ended up with some interesting ideas. Here is the email chain slightly edited. Its not a doctoral thesis, just a ‘back-of-a-napkin discussion on stats. AL At Home on the Court mentioned in a recent post about the statistical significance of the sample size in volleyball stats - and made the point that the sample sizes are not big enough in a match to really mean anything from a predictive point of view. I suspect there are both simple and complicated ways to determine if the sample size is appropriate to be predictive or not (as opposed to simply a mathematical representation of what happened). So - what's the quick answer to this? KJ The short version is “it depends”. There’s not really any such things as a “big enough” sample size, only sample sizes that give enough “power”. The more accurate you want to be, the more samples you need. I would say that 20-30 games is about what you’d need in most

I try to focus on more general themes for this blog but I've been thinking about some VERY basic volleyball statistics this morning and got on a bit of a roll. Below are two charts documenting the average heights of the Australian teams, and the eventual champions, at all major international competitions Australia has competed in since 1998. For those interested in this sort of stuff, the FIVB does a good job on their site .