Referee Review 2013: Was there Home/Away bias

By Walter Broeckx

 

This article is part of the series of the Referee Review 2013. You can find links to earlier articles on the bottom of this article.

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Last year in our season review we pointed at the fact that we found a Home and Away bias. And this was based on calculating the incorrect decisions and then see who was receiving the favour of that wrong decision. We then showed that there was a bias in favour of the home team. So now with the new system we will be able to see in detail how this has worked out in the last season and we then will give you the total of all incorrect decisions and look at who was on the good end of that decision.

 

So will we be able to see again that there is a home bias? Or will things have evened out a bit? Referee Decisions and Untold Arsenal will give you the answer in the coming days. Keep in mind of course that Home/Away bias is just one of the type of biases that we can have or find. We can also have team bias and that is something we will talk about later in this series. We also find it difficult to compare with what we found last season as the numbers and events we covered were much changed to last season.

 

First we will start with the different decisions that we covered in our reviews.

 

Total incorrect	Favour  Home	Favour Away
2541	1346	1195
Total incorrect	Favour Home	Favour Away
2541	53%	47%

 

We had a total of 2548 wrong decisions in the games we reviewed. And in total we found that 1346 of those incorrect decisions favoured the home team. And 1195 of those decisions favoured the away team. Or in % we had 53% in favour of the home teams and only 47% in favour of the away team.

 

So it is fair to say that the Home/Away bias is still there. But it gets rather interesting and sometimes even strange when we look at the different decisions in detail.

 

We will now first have a look at the important decisions and in the table I will show you each type of decision and the home and away bias both in numbers and in %.

 

Call	Total incorrect	Fav Home	Fav Away
2ND YELLOW		20	18
	38	53%	47%
	Total incorrect	Fav Home	Fav Away
FOUL		447	423
	870	51%	49%
	Total incorrect	Fav Home	Fav Away
FREE KICK		407	379
	786	52%	48%
	Total incorrect	Fav Home	Fav Away
GOAL		27	18
	45	60%	40%
	Total incorrect	Fav Home	Fav Away
OWN GOAL		1	1
	2	50%	50%
	Total incorrect	Fav Home	Fav Away
PENALTY		36	40
	76	47%	53%
	Total incorrect	Fav Home	Fav Away
RED		22	24
	46	48%	52%
	Total incorrect	Fav Home	Fav Away
YELLOW		180	155
	335	54%	46%
	Total incorrect	Fav Home	Fav Away
		1140	1058
	2198	52%	48%

 

If we look at the last number we see that the major decisions have been slightly in favour of the home teams.

 

And to start with the most amazing thing and I hope the colour red is copied in to the article so you can see that when it came to penalties and red cards the most decisions went in favour of the visiting teams. I must tell you that this is a rather amazing result from our reviews. But we cannot but confirm that in the reviews we did the away teams got more benefit from wrong penalty calls and wrong red cards decisions than the home teams.

 

But visiting teams must not celebrate too soon because when we look at the wrong goal decisions we see that 60% of those decisions went in favour of the home team. And that is the largest bias difference we can find in this table. So the most important decision of them all (goals) is still largely in favour of the home teams.

 

Later on in this series we will try to go in to detail for each of those decisions and link them with the teams involved. Maybe we could see some strange things and patterns coming up at that time? But that is for later.

 

We can also see that the decisions on fouls and free kicks are rather close to the 50% margin in general. I think this is good news and confirms a feeling I got during the season at times. Of course there are exceptions but it is fair to say that in general the refs have done rather well when it came to calling the fouls.

 

It is obvious from these numbers that the incorrect goals is a very big worry for me and should be for whoever is involved in football. Goals decide who wins games and who gets the points. So we really should be doing something about it. The least that can happen in my opinion is an immediate check if a goal was correct by the 4^th official or a video ref.

 

In a next article we will focus on the not that important decisions and who knows we might see some surprising numbers.

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Earlier articles:

1. Who reviewed the games

2. What we did and what next

3. All the decisions in numbers

4. The first at times astonishing numbers