To investigate this hypothesis, I grabbed some free SPL match results data from the demo version of the XMLSOCCER.COM API and wrangled it into R using the XML package. The dataset contains > 3100 matches going back to the 2000-2001 season, and dozens of match-related variables.
By the way, how lucky am I to be a Scottish football fan and data enthusiast? Just ask XMLSOCCER.COM's website.
"If you for some odd reason is [sic] only interested in the Scottish League anyway, lucky you - you just found a great API for FREE!"Jackpot.
I used the variables AwayGoals and HomeGoals to calculate the average goal difference for each away team and created a simple bar plot to visualize the results.
Goal difference is a better measure of team peformance than points earned because it takes into account the quality of the win or loss. For example, a 1-0 loss suggests a close match, while a 6-1 loss suggestes a pummeling. This is an important qualitative difference not captured by simply using points earned as a metric, since in both cases the losing side would get zero points.
As expected, Rangers and Celtic are the only Scottish clubs to have positive average goal differences away from home since 2000, because they tended to win most of their away matches, typically by a relatively large margin.
But the club in 3rd place may surprise you.
It's Inverness Caledonian Thistle (ICT), a "small" club from the Scottish highlands. The Edinburgh club Hearts is a close 4th.
This is a remarkable observation, not just because ICT has fewer resources than bigger clubs such as Hearts (historically speaking), but because the median driving distance for ICT to away locations is 156 miles!
The histogram below shows the frequency of away locations for ICT within different distance "bins" (based on Google Maps). As you can see, most of the locations the highlanders would have to travel to are > 100 miles away. Only Ross County travels further, but the Dingwall club's away record is worse than their highland rivals.
This result calls into question the commonly held notion in football that traveling far for a match puts the away team at a disadvantage. By this logic ICT should have one of the worst away records in the SPL. On the contrary, the highlanders are in fact the best of the rest when it comes to away goal difference.
What if we look at Total Shots Ratio (TSR) instead? TSR is probably the best measure of what a team does on the pitch. According to TSR pioneer James Grayson, "the higher a team's TSR the more they control the ball." This simple index is calculated as follows.
TSR = Total shots for/(Total shots for + Total shots against)
Take a look at the bar plot below. Again, third place is a surprise.
Hello Falkirk!
The Bairns had a decent run in the top flight between 2004-2010. And despite having a relatively high average TSR away from home during this time period, Falkirk was relegated to what is now the Scottish Championship.
Of course, this calls into question the predictive value of TSR...but that's a post for another time.
Hello Falkirk!
The Bairns had a decent run in the top flight between 2004-2010. And despite having a relatively high average TSR away from home during this time period, Falkirk was relegated to what is now the Scottish Championship.
Of course, this calls into question the predictive value of TSR...but that's a post for another time.
