Friday, 19 June 2020

Sound of Silence

There are a number of people jumping on the "no crowd / no home advantage" bandwagon, although it is very early days in the experiment and the number of trials is still very low.

One typical posting is from BitEdge where the latest article has the title "Why EPL away teams are good value this season".

While he doesn't mention it, blindly backing Aways this season had actually been profitable with an ROI of 4.6% - don't get too excited - up to the enforced break, but the crux of the article is that Away sides should continue to show value in empty stadiums.

A full season of 380 matches is a small sample, so a sub-set of only 92 isn't likely to give us too much information, but better than nothing.

The author then states that "the good news is that odds compilers are yet to make allowances for this".

I'm not sure who these "odds compilers" are because prices are determined by the markets, and anyone offering odds out of line with the market wouldn't be in business for long.

He suggests that five teams are worthy of "consideration" whatever that means adding that "all five are realistic shots. But what’s remarkable is every single one of them is still available at an odds-against price. The prices are assuming home advantage still exists."

Having just claimed that the prices have not yet "made allowances" for this expected loss of Home advantage, this now becomes "an assumption" which is a huge difference. It's also highly unlikely that the market, with some highly sophisticated participants, hasn't taken this into account.

I'm also at a loss to understand what the significance of being odds-against is. 

A price is the probability, and is value if it is greater than the true probability. 

A price of 1.01 can be value, a price of 1000 may not be value, and there is absolutely nothing magical about a selection being odds-against.  

The author claims to make a 4% return from sports betting, which would be phenomenal if true, but perhaps he is new to the EPL. 

If you're interested, the five to "consider" this week are Southampton, Manchester United, Leicester City and Arsenal. Sheffield United were the other selection, but they failed to win on Wednesday.

For the record, backing Away teams that are not-odds on does have a higher ROI this season so far than backing ALL Aways with an ROI of 6.4%but the trouble with small samples is that the profitability of blindly backing the Away team would actually be a loss were it not for just one result (Wolverhampton Wanderers win at Manchester City last October).  

Regarding Home Advantage, an October 2002 study titled "The Influence of Crowd Noise and Experience upon Refereeing Decisions in Football" concluded that:
The noise of the crowd influenced referees' decisions to favour the home team. It is suggested that referees' decisions are influenced by the salient nature of crowd noise, the potential use of heuristic strategies, and the need to avoid potential crowd displeasure by making a decision in favour of the home team.
The results found that:
The presence of crowd noise had a dramatic effect on the decisions made by referees. Those viewing the challenges with background crowd noise were more uncertain in their decision making and awarded significantly fewer fouls (15.5%) against the home team, compared with those watching in silence.
But this is nothing new. What is new is the possibility to more accurately evaluate this advantage, although I suspect it has eroded somewhat since 2002 by the implementation of goal-line technology, VAR and modern schedules as I have written about before. I suspect this will be a returning topic over the next few weeks.

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