Service Error and Eff Change


*Check out the Eff Change posts if you haven’t. Output, Input, Eff Change

Returning to the very first question – How aggressively do we want to serve?

Here is what team service error% looks like graphed against the average Eff Change per serve in each match. Again we see an inverse relationship between the two variables, suggesting that an increase in SE% tends to result in less effective serving.

To be clear, this is not an absolute. Michigan State arguably had the best serving performance with around 0.175 improvement in Win Efficiency per serve, while also missing more than 5% of their serves. But as a general trend, teams with better serving performances also tended to have lower error from the endline.


This trend becomes even more pronounced when you drill down into the player specific view of each match. After removing servers with fewer than 5 serves in the match, the above results echo what we’ve already seen. Making fewer errors is associated with typically better Eff Changes.

One of the reasons this may feel strange is that we’ve become accustomed to service error. Again, this isn’t to say that those who make errors from the line can’t have good serving performances – just look at those Bailey and Kranda matches at the top – but as an overarching trend: more risk, less reward.

A logical next step may be to break this down by type of serve. Does the increase in risk by hitting a jump float make it less valuable than a “flean” standing float that achieves similar outcomes (hey Karch). Is hitting a full jump spin serve worth the risk? And how does this change when you look at the men’s collegiate game?

Or is it more important to look at who you’re serving against? Adding 5% more error against Michigan State add more value than adding 5% more error against Nebraska. If Nebraska is going to pass and attack similarly, then why add the errors? But if that 5% is what drops MSU from hitting .350 in serve receive to hitting .150 because they’re not running quicks from off the net or something – then maybe that’s where the value lies, in the specific matchups. And eventually…in the specific rotations?

Food for thought. Nibble away…