The penalty taker’s advantage

After my post last week about Jamie Vardy’s Shots on Target conversion rate, the Fantasy Premier League manager with whom I had originally been debating – JMO – replied to say that if penalties were removed the Leicester City striker was close to the trend line.

He raises an interesting point: should we be including penalty kicks when looking at player shooting statistics?

Penalty conversion rateI looked at the recent penalty conversion rate over the past few seasons and discovered that while it fluctuates a fair bit, it’s fair to say that penalties are converted into goals at around double the average Premier League Shots on Target (SoT) conversion rate. Therefore, it isn’t really fair to lump those goals – and those attempts – in with regular Shots on Target.

If we exclude penalties from player data, what does this mean for the penalty takers?

Here’s the Shots on Target trend line for those players who have taken a penalty this season, including those who have missed:

SoT conversion with penalties

Note: The dots for Yaya Touré and Glenn Murray are in the same place

The conversion rate for penalty takers is 41 per cent, with Vardy sitting well above it on 55 per cent. The next chart shows the same players with penalty attempts and penalty goals removed.

Shots on Target conversion trend line without penalties

Note: The dots for Sigurdsson and Cabaye are in the same place

JMO was right that Vardy’s conversion rate comes down – it falls from 55 per cent to 50 per cent. However, Vardy remains well above the trend line because the conversion rate for most of those players who have scored penalties this season has also dropped. The conversion rate among penalty takers for regular Shots on Target is 32 per cent.

Just 18 players have taken a penalty though, which is a small sample size. The final chart shows what effect removing penalties has in a much larger pool of players – all those who have played at least 300 minutes (which was selected as the time period because Sunderland penalty taker Adam Johnson has only played 364 minutes this season).

SoT conversion - players 300 minutes +

To avoid the chart becoming messy I have only picked out the three penalty takers that have converted more than one penalty this season. The grey dot shows their statistics with penalties and the red dot shows them without penalties.

With penalties removed, Riyad Mahrez is pretty close to the trend line and not reliant on penalties to boost his performance. It’s a different story for Yohan Cabaye as removing penalties shows the Crystal Palace midfielder is under performing a little when it comes to natural Shots on Target conversion. At the other end of the chart, Vardy is still over-performing the general trend, although without penalties the gap does come down from 23 to 18 per cent.

To be fair to Vardy, the conversion rate among his rivals for a place in Fantasy Premier League teams – forwards who have played at least 500 minutes this season – was 40 per cent when I looked at the data last week. Vardy may be over performing a bit, but given how often he is getting his shots on goal he remains a good pick.

Finally, it’s worth remembering that penalty takers are popular FPL players in part because of the high rate at which penalties are converted. Players that are performing well when the effects of penalties are stripped out should be great buys if they have penalty duties too.

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5 thoughts on “The penalty taker’s advantage

    • Haha, maybe. I was just interested to see what difference penalty taking made to SoT conversion. Now I know and I thought I would share what I had discovered. 🙂

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  1. Ruth_NZ says:

    Watford had conceded 2 penalties in 5 games prior to today. That, the high level of big chances they had also conceded and the Leicester home fixture caused me to captain Mahrez.

    You can guess that I wasn’t best pleased when I came home to discover that Leicester had indeed been awarded a penalty and that Vardy had persuaded Mahrez to let him take it.

    That sort of thing shouldn’t be allowed. 😕

    Like

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