Opportunity

Tyre tracks on Mars from the Opportunity Rover.

Last week, NASA announced that “One of the most successful and enduring feats of interplanetary exploration, NASA’s Opportunity rover mission is at an end after almost 15 years exploring the surface of Mars and helping lay the groundwork for NASA’s return to the Red Planet”.

Opportunity landed on Mars on 24 January 2004. It was designed to last 90 Martian days and travel 1,000 metres. It exceeded its life expectancy by 60 times and traveled 45 kilometres. Its resting place on Mars is, by delightful serendipity, Perseverance Valley.

Opportunity’s history is a great metaphor many endeavours. Last week on hearing about the end of NASA’s contact with the rover, I thought about all those who have charted the world of performance in sport. The image of Opportunity’s tracks on Mars provide a great reminder of the tracks each of us follow in our own journeys of discovery.

Our tracks in analysing performance come from some very basic technologies and, in the case of some of the foundational ideas about performance, remain as relevant today as they were when they were first recorded.

When will goals be scored in the group games at #AsianCup2019?

The group games are about to start at the 2019 Asian Cup football tournament (link).

I have used goal scoring data from the group games of the previous two Asian Cup tournaments to derive some naive priors for when goals will be scored in the group stage of the tournament.

It will be interesting to see the early trends in goal scoring. The previous goal scoring patterns (2015, 2011) were:

My data from goal scoring in 2015 and 2011 are:

Time Interval20152011
0-15 minutes0.100.19
16-30 minutes0.130.17
31-45 minutes0.250.19
46-60 minutes0.160.14
61-75 minutes0.160.11
76-90 minutes0.200.21

Elo ratings and FIFA rankings prior to #AsianCup2019

The most recent Elo World Football Ratings were published on 3 January 2019 (link) and the FIFA Rankings on 20 December 2018 (link).

At the start of the 2019 Asian Cup (link), the ratings and rankings of the teams in the competition are:

TeamEloFIFA
Iran1929
South Korea2353
Australia3541
Japan3650
Syria5874
Uzbekistan6095
Saudi Arabia6269
Iraq6388
Oman7482
Qatar7793
China8076
UA Emirates8579
Lebanon9181
Jordan97109
Bahrain99113
North Korea100109
Palestine11299
Thailand113118
Vietnam124100
Kyrgyzstan14091
Turkmenistan150127
India15597
Yemen164135
Philippines169116

In the 2015 Asian Cup tournament, the performances against Elo ratings were:

  • Higher Elo rated team scores first and wins: 22 games (69% of games played)
  • Higher Elo rated team does not score first and wins: 2 games (6%)
  • Higher Elo rated team scores first and loses: 3 games (9%)
  • Higher Elo rated team does not score first and loses: 5 games (16%)

I am going to monitor performance against Elo rating in 2019 and will start with these naive priors:

  • 0.69 Higher Elo rated team scores first and wins
  • 0.75 Higher Elo rated team wins
  • 0.25 Higher Elo rated team loses

The tournament starts this evening with the United Arab Emirates v Bahrain Group A game in Abu Dhabi (link).