It may not seem a good time to be predicting relegation for Reading (just after they’ve beaten us), QPR (buoyed by big new signings with an escapologist in charge) and Aston Villa (didn’t we somehow contrive to make even them seem half-decent?). But John McCormick has been pottering around with his blinding statistictal science again, attempting to calculate the impact fluctuating goal differences can have on survival prospects. As things stand, he sees safety for Sunderland but not by a comfortable margin and a possible lifeline for Reading, at Wigan’s expense …
Following on from Pete Sixsmith’s comments on the Guardian’s take on Premier League statistics, John McCormick decided to do his own piece of number crunching and what follows is the fruit of his labours. His piece was completed before the Hackers disrupted the site and before the Spurs game kicked off.
Last season was the first in five years where goal difference
has determined the title, and only once in those five years has a relegation been decided on goal difference.
How do I know? I’ve been playing around with the interactive tables on the premier league website (http://www.premierleague.com/en-gb.html). If you pay that site a visit in the next few days you’ll find their half-term report, where experts give opinions on best goals and managers, and predictions for the top four. It’s a good site but I couldn’t find any picks for relegation or teams that will scramble to safety, and there was no mention of SAFC. No wonder Sixer can’t find anything in “The Guardian” if the Premier League ignores us.
But what else can you expect when the Premier League lacks the top-class team you will find writing for the Salut site? Good though we are, though, we don’t expect to be taken too seriously. We’re a fans’ site for fans and we want to provide banter and fun that you won’t get from a club or the premier league, along with analysis and content that will get you thinking. I believe we succeed in our aim and in that vein, here’s my last posting of 2012. It contains some figures that Sixer didn’t find and comes with my my best wishes for 2013.
At the start of the season we had a solid defence. We couldn’t buy a goal, but we didn’t concede many and our goal difference remained relatively healthy. Then things changed. Our scoring improved but our defence became leaky. As a result our goal difference became negative.
This got me thinking. Can goal difference tell us anything? I began to look into it, starting with mid-season positions and goal difference over the last five years.
In some years teams arrived at 19 games at different times, so I had to work backwards and forwards to make a table which shows the situation for the last five seasons:
The following table shows Premiership position and goal difference after 19 games:
|Pos||SAFC (13th)||1||SAFC (7th)||2||SAFC (10th)||-3||SAFC||-5|
|17||QPR||-15||Fulham||-4||West Ham||-7||Boro r||-11||Wigan||-15|
|19||B’burn r||-13||Wolves||-12||Hull r||-22||B’burn||-14||SAFC||-21|
|20||Bolton r||-19||W.Ham r||-13||P’mouth r||-11||WBrom r||-21||Derby r||-34|
|also relegated||Blackpool (11th)||-5||Burnley (16th)||-19||NUFC (12th)||-2||Brum (14th)||-9|
In every season some teams with a poor goal difference have stayed up at the expense of others in better positions. For example, last season Wigan went into the new year at -20 but survived, whereas Blackburn and Wolves, both with -13, didn’t. The season before Wigan had -14 after 19 games and stayed up while Birmingham had a goal difference of -6 and then won a trophy but still slipped through the trap-door.
There’s something else. In all but one of the last five seasons a team outside the bottom five at the half-way stage has gone down. Most had been recently promoted, although our friends up the road proved an exception. They had all been in mid-table with, Burnley excepted, goal differences that gave little concern.
Goal difference can’t help to identify escapees and even a mildly negative goal difference is no guarantee of safety. It doesn’t let us form rules, or even make a prediction. We can say Reading are bottom at Christmas and therefore doomed and I’d say QPR, bottom after 19 games, will be joining them. However, this is a result of their failure to win points and not their poor goal differences.
We, of course, have just enjoyed seasonal good cheer by the barrowload. Does this mean we have turned our season around? I’d like to think we have, and maybe in such cases goal difference will give us confirmation. (Written before the Spurs game – Ed) I’d expect goal differences between the top and bottom clubs to widen between Christmas and May. I’d also expect the gap to increase more or less proportionally if teams stay as they are, as a goal difference of +20 after 19 games will have grown to +40 after 38 games, and -20 will become -40.
Are these assumptions correct?
They are for most of the clubs who find themselves in the bottom five after 19 games and who then go on to be relegated. However, the teams that stay up invariably improve their goal difference in relative terms. In our first season back in the premiership Derby went from -34 to -69, Birmingham from -9 to -16 and Reading from -11 to -25. They were relegated. We, on the other hand, went from -21 to -23, indicating a massive improvement. It appears that, for the bottom teams, an improved goal difference in the second half of the season is a key factor in survival. This shouldn’t be surprising as it requires either an improved defence or attack, or both, so points are not lost to defeats and may be gained by wins.
Where teams improve equally those starting with fewest points will always lag behind. Last season Wolves went from -13 to -42 and Blackburn from -13 to -30 and both went down. Bolton bucked the trend by ”improving” from -19 to -31 but they couldn’t catch QPR who also ” improved”, from -15 to -23, or Wigan, who did even better and remained at -20.
So, while looking at goal differences at any single time is of little use, observing trends might have possibilities as a predictor. This season’s midpoint has seven points separating six teams occupying 13th place downwards to the third relegation slot. This group includes Fulham, whose goal difference has drifted from +5 to -5, and Villa, whose goal difference has recently dropped like a stone. Who is at greater risk? An 8-0 thrashing wrecks goal difference but only loses three points. A series of 1-0 defeats loses many more points but goal difference only drops slowly. I’m going to stick my neck out and say that the five whose goal differences show the greatest improvement in the second half of the season will avoid relegation, irrespective of their points on Boxing Day, and a consistent decline will point to the doomed team.
And which way is our goal difference heading?
We’re heading downwards, which is not promising but we aren’t plunging off a cliff. We are overcoming our weakness in attack, so to reverse this trend we just need to get our defence back to what it was at the start of the season. Clean sheets against Southampton and City suggest we might be doing this. I’ll revisit around the end of January to see if we are. Until then, keep the faith.
See also: Monsieur Salut talks all things Sunderland at ESPN FC:http://soccernet.espn.go.com/blog/_/name/sunderland?cc=5739
Peter Sixsmith has been watching Sunderland since the days of Cec Irwin and Ambrose Fogarty. In that time he has witnessed some dross and he now adds Tuesday’s visit of the Premier League’s bottom side to that collection. Much of the pre match speculation was about the effect Harry Redknapp would have on the game but in truth QPR could have had Louise Redknapp in the technical area and the outcome would probably have been the same – such was the dearth of attacking options provided by Martin O’Neill’s boys. As a contributor to Total Sport said earlier this evening: “The Samaritans were outside the ground handing out leaflets after this one.” We’ll let Sixer talk it through.