On any given week during peak soccer season, FiveThirtyEight offers projections for dozens of club soccer matches across the globe. The sheer volume of matches taking place this time of year can be paralyzing. With that in mind, we’ve added a feature to our club soccer predictions that rates upcoming matches on their quality and importance. You can use this page to pick a few good ones to be sure not to miss.
This week’s biggest match — rated an overall 96 out of 100 — is today’s Champions League round of 16 first leg between Real Madrid and Paris Saint-Germain. This is a bit of a no-brainer — it features Neymar and Cristiano Ronaldo leading the second- and third-best teams in the world against each other in a high-stakes clash. But there are some other good matches to watch: Borussia Dortmund and Atalanta — two of the best eight remaining teams in the Europa League — play each other on Thursday in the round of 32. If we dig deeper, Empoli and Parma — two teams fighting for promotion and the league title at the top of a very tight Italian Serie B — play each other Saturday. And Manchester United plays Chelsea on Feb. 25 in the Premier League in what is a pivotal match for Champions League qualification.
Here’s how we calculate our match ratings:
Quality is simply a measure of how good the teams are. Specifically, it’s the harmonic mean of the two teams’ Soccer Power Index ratings. (We’re using the harmonic mean instead of merely averaging the two ratings because in lopsided matches it limits the impact of very high or low ratings, resulting in a more balanced number.) Because every team has an SPI rating between 0 and 100, our match quality stat also ranges from 0 to 100.
Importance is a measure of how much the outcome of the match will affect our forecast for how likely the two teams are to win the league, or be relegated or promoted, among other things. To calculate it, we generate probabilities conditional on each team winning the match and then find the difference between those two possible numbers.
We consider different factors depending on which league the match is being played in. For some leagues, our forecasts cover winning the league and qualifying for the Champions League, for example.
We take a weighted average of the change in each applicable factor and scale the result to between 0 and 100. All leagues are treated equally when calculating importance, so a match to decide the winner of the Swedish Allsvenskan would rate just as high as a match to decide the winner of the English Premier League.
The overall match rating is just the average of quality and importance.
Visit our club soccer predictions to explore the ratings of all the upcoming matches yourself.