AFCON 2015: Deserving Finalists, Skill Overcame Luck, and Luck Ran Out

Cast your mind back to one of my earlier posts on the 2015 Africa Cup of Nations where I used statistics to look at the skill and luck teams had in the group games. According to these stats, 6 of the Quarter-Finalists had benefitted from a lot of luck in the group stages. This came from my PDO vs SoTR chart: 6 of the Quarter-Finalists had PDO values of over 1000. 

Now, if you recall PDO is a measure of luck - the higher the number the more the luck the team has had. You arrive at a team's PDO figure by adding the percentage of goals scored from shots on target, to the percentage of goals conceded from shots on target against them. More broadly, the score percentage and the save percentage. The SoTR - Shots on Target Ratio - is the proportion of shots on target a team has of the total number of shots on target by the two teams. The higher this number is, the more skill a team has as it indicates they dominate the number of shots on target.

For reference, I bring back the PDO vs. SoTR chart from the group stages below. The chart clearly shows that Ghana and the Ivory Coast exhibited the highest skill - as indicated by SoTR - in the group stages of all the Quarter-Finalists (those teams with a Gold or Silver icon beside their three-letter country code).

This chart got a bit of love on Twitter in the past couple of days as it shows that despite a limited sample size (16 teams competing over the course of 24 matches) the SoTR (Skill) PDO (Luck) comparison yields some intuitive insights as to why teams succeed and/or fail. Additionally, the simple fact that there are no "lucky" teams - as shown by PDO, anyway - in the final shows that using this chart has some power in explaining things in this particular tournament.

Again, this is a small sample of data, and it must be stressed that Ghana faced, in Guinea and Equatorial Guinea, two massively inferior opponents in the knockout stages. The Ivory Coast have overcome bigger challenges to get to the final, so it will be an interesting one to watch. If, the skill levels (SoTR) continue to hold some predictive power - if I could call it that? - Ghana looks like the winner.

I've said it before. I'll say it again: I can't bloody wait for this final!