Sunday, 19 June 2011

England v Sri Lanka, 3rd Test at the Rose Bowl: Day 3

Good morning all! As the action gets underway on day 4 in Southampton we're here to give you a quick update of the WPA situation in this Test as of the end of the third day. Apologies for not making it on yesterday, by the way...

So here is the summary of how the players have contributed to their team's chances of winning/losing/drawing the match (we don't include rain in this table, but it has certainly been the most dominant force in the game so far!):


Eng win
SL win
draw
Trott -4.2% 6.9% -2.7%
Tremlett 40.3% -20.5% -19.8%
Pietersen 9.6% -8.0% -1.6%
Anderson 10.5% -9.9% -0.6%
Broad -9.8% 5.2% 4.7%
Bell 3.3% -2.5% -0.8%
Cook 3.8% -5.1% 1.3%
Strauss -3.2% 5.7% -2.6%
Swann 3.2% -1.1% -2.1%
Prior -0.3% 0.2% 0.1%

SL win
Eng win
draw
Wel'ara -0.2% 3.4% -3.2%
Thiri'ne -5.9% 8.3% -2.4%
Fernando 3.5% -6.2% 2.7%
Sang'ara -6.2% 9.0% -2.8%
M'Jay'dene -6.2% 11.4% -5.2%
Herath -2.1% 3.3% -1.2%
Lakmal 0.1% 5.4% -5.5%
P.Jay'dene 1.0% -2.6% 1.6%
Perera -5.8% 9.4% -3.7%
Parav'ana -6.4% 9.2% -2.8%
Sam'eera -1.4% 6.7% -5.3%

Unsurprisingly, Tremlett's outstanding 6-48 in Sri Lanka's first innnings was massive, and he is the clearly the player of the match so far, earning around 40% of a win from England. Anderson and Pietersen have also made significant contributions of ca. 10% of an England win. It looks like a sorry situation for the Sri Lankans, who have barely seen the game swing in their direction in the match so far.

Here is the story in graphical format; England have a decent chance as it stands currently, in large part due to Kevin Pieterson's brisk scoring pace yesterday evening:



Thursday, 16 June 2011

England v Sri Lanka, 3rd Test at the Rose Bowl: Day 1

We return with a brief cricketWPA update of the 3rd Test between England and Sri Lanka. As so few overs were played, we thought we'd hold off on the graph for today, but here is the tally of the match so far, in terms of wins/losses/draws (Prior has been penalised for byes):



Eng win
SL win
draw
Tremlett 19.9% -13.2% -6.7%
Anderson 18.2% -13.1% -5.2%
Broad -5.6% 3.4% 2.2%
Prior -0.3% 0.3% 0.0%

SL win
Eng win
draw
Thim'ne -5.9% 8.3% -2.4%
Sang'ara -6.2% 9.0% -2.8%
M.Jayd'ene -7.0% 10.6% -3.6%
P.Jayd'ene 1.2% -2.6% 1.4%
Parav'ana -6.4% 9.2% -2.8%
Sam'eera 3.4% -5.8% 2.4%

Clearly Tremlett and Anderson were the stars of the day, bagging large chunks of WPA with two wickets apiece. They seemed to benefit from the conditions in their early spells, whilst late in the day Prasana Jayawardene and Samaraweera were able to trim England's win probability by 8%. Another 50 or so wicketless runs would have a greater impact than that. One more wicket means the tail is exposed, and that yields plenty of WPA!

We should be looking at tomorrow morning as a turning point due to the aforementioned game sensitivity to runs and wickets; instead we'll be probably be watching an Ashes highlight reel as the Win Probability leaks slowly away.

Wednesday, 8 June 2011

England v Sri Lanka, 2nd Test at Lord's: Day 5

So, somewhat inevitably, the second Test rolled to a draw. The fifth day at Lord's was rather inconsequential to be honest, so we won't linger on it (or the window incident). Here is the tale of the five days, in terms of how much each player contributed to his team's chances of winning/losing/drawing the match:


Eng win
SL win
draw
Tremlett 14.9% -7.3% -7.7%
Morgan 7.7% -9.6% 1.8%
Strauss -8.2% 21.5% -13.4%
Finn 0.3% 2.4% -2.7%
Trott -0.5% 0.0% 0.5%
Cook 1.8% -26.7% 25.0%
Bell -5.5% -1.3% 6.7%
Pietersen -11.8% 7.9% 3.9%
Broad -18.6% 10.5% 8.1%
Prior 17.7% -21.7% 4.0%
Swann -26.1% 11.6% 14.5%

SL win
Eng win
draw
Maharoof -19.2% 16.8% 2.4%
Weleg'ara 6.0% 6.2% -12.2%
P.Jay'dene 2.3% -4.5% 2.2%
Sang'ara -3.1% 5.1% -2.0%
Parav'ana 0.0% -9.2% 9.2%
Sam'eera -3.0% 4.0% -1.0%
M.Jay'dene 4.2% -8.7% 4.5%
Herath -6.7% -8.1% 14.8%
Lakmal -4.2% -0.2% 4.4%
Fernando -13.4% 4.7% 8.7%
Dilshan 19.4% -29.3% 9.8%

And here is the story of the match in graphical form; note the extent to which England's decision to keep batting on hindered their chances of winning:



Tuesday, 7 June 2011

England v Sri Lanka, 2nd Test at Lord's: Day 4

The fourth day of the Test began with yet more bad weather, leaving us to wonder what could have been had we had a full four days' play. Despite this, Swann and the quicks actually did quite a good job of restraining the Sri Lankans, leaving them all out on 479. The draw probability took an early blow in England's second innings whan Strauss was dismissed for a duck, but soon rebounded as Trott and Cook began to build a healthy lead.

Here's how much each player has altered his team's chances of winning the Test match, as of the end of the fourth day:



Eng win
SL win
draw
Tremlett 10.6% -7.3% -3.4%
Morgan 8.3% -9.6% 1.3%
Strauss -8.2% 21.5% -13.4%
Finn 5.2% 2.4% -7.6%
Trott -2.1% 0.0% 2.1%
Cook 11.3% -26.6% 15.4%
Bell 1.3% -1.3% -0.1%
Pietersen -11.4% 8.1% 3.3%
Broad -16.4% 10.5% 6.0%
Prior 14.3% -17.7% 3.5%
Swann -19.4% 11.6% 7.8%

SL win
Eng win
draw
Maharoof -19.2% 16.8% 2.4%
Weleg'ara 6.3% 3.8% -10.1%
P.Jay'dene 2.3% -3.3% 0.9%
Sang'ara -3.1% 0.2% 2.9%
Parav'ana 0.0% -5.2% 5.2%
Sam'eera -3.0% 7.2% -4.2%
M.Jay'dene 4.2% -4.4% 0.3%
Herath -6.7% 3.3% 3.4%
Lakmal -4.0% 0.2% 3.8%
Fernando -13.4% 12.0% 1.5%
Dilshan 19.4% -29.3% 9.8%

Dilshan remains the most influential player of the match so far, having contributed 19.4% of a win for Sri Lanka, and taken away almost 30% of a win from England. Cook now stands out as England's top performer with 11.3% of an England win added and 26.6% of a Sri Lanka win taken away. Strauss's poor run of form continues, and he may be on the verge of a WPA 'wooden spoon', scoring only 4 runs in the match and contributing 21.5% to Sri Lanka's chances of winning.

Here is the match so far, in graphical form:



Geeks' note:

Please take our estimates of 'unlikely outcomes' with a pinch of salt (eg in this case the likelihood of a SL win). The model is very good at dealing with most regular situations but it is not yet equipped to deal with 'fat tails'. For the mathematically inclined, it's because we currently base our projections on binomial distributions for each potential future batsman. This generally is a good approximation, particularly early in the game looking forward, but in reality the probability distribution function should not be binomial. Unsurprisingly, (say in the case of a recognised batsman) there is a greater chance of dismissal for under ca. 15 runs than the binomial predicts, and a lower than predicted chance of dismissal for 15-40 runs or so... So basically, we tend to underwight the probability of a dramatic collapse.

We have always been aware of this and have been working towards sorting it out, but suffice to say, SL's win probability is very small, but not as small as the graph implies. This doesn't actually affect the players' WPA numbers very much, and that really is our main concern, the graph is something of an illustrative sideshow... However we still believe SL's collapse in 24 overs at the end of the last Test was truly extraordinary. We will also write more about how the model works in the future and look forward to hearing your thoughts!

Monday, 6 June 2011

England v Sri Lanka, 2nd Test at Lord's: Day 3

Day 3 at Lord's was something of a disappointment, with Dilshan falling just shy of his double century and rain yet again getting in the way of a perfectly good Test match. Who'd be a batsman in early summer Test cricket in England? Great batting doesn't win Tests, it draws them; poor batting loses them.

Anyway, whilst rain was always a possiblility, our program pootled along innnocently expecting all three days to be played out in full. Whilst this may distort the players' WPA (e.g. credit them with more wins than it should given expectations of overs lost), it does give us a good idea of how much the rain actually changed the game. Indeed, as illustrated by the graph below, it took 12.1% of a win from England and 28.8% of a win from Sri Lanka, increaing the draw probability by ca. 40%. As can be seen in the players' contributions below, Dilshan had earned Sri Lanka 19.4% of a win, but alas he was eclipsed by the weather...


Eng win
SL win
draw
Tremlett 1.4% -4.8% 3.4%
Morgan 8.3% -9.6% 1.3%
Strauss -6.1% 8.5% -2.4%
Finn -1.3% 3.0% -1.7%
Trott -7.0% 9.2% -2.3%
Cook 10.1% -11.6% 1.6%
Bell 1.3% -1.3% -0.1%
Pietersen -10.3% 10.1% 0.2%
Broad -16.9% 8.9% 8.0%
Prior 14.9% -18.2% 3.4%
Swann -19.1% 10.6% 8.6%
SL win
Eng win
draw
Maharoof -13.3% 10.0% 3.3%
Weleg'ara 3.5% 0.2% -3.6%
Dilshan 19.4% -29.3% 9.8%
Sang'ara -3.1% 0.2% 2.9%
Parav'ana 0.0% -5.2% 5.2%
Sam'eera -0.8% -0.6% 1.4%
Herath -9.7% 7.5% 2.3%
P.Jay'dene 3.4% -3.0% -0.4%
M.Jay'dene 4.0% -8.0% 4.0%
Lakmal 4.1% -1.0% -3.2%
Fernando -6.2% 6.1% 0.0%

And here is the Test match up to day 3, in graphical format; note the impact of the rain (discussed above):

Sunday, 5 June 2011

England v Sri Lanka, 2nd Test at Lord's: Day 2

We always tend to forget how evenly matched teams are in International cricket. Maybe it's just the same human tendency that forces us to extrapolate things like short term economic trends into the distant future or maybe it's just Sky and the others looking for things to say. But one way or another, Sri Lanka were written off; Dilshan, Sangakkara and Jayawardene (some of the best batsmen in Test cricket) were going to fall at some point, and England's 486 was going to be looked back upon as the first step in another impressive Test match victory.

It may still be that way, but England did get a rude awakening as Dilshan rattled on to 127 not out. Oh yes, now we remember- they can bat too! Now we're expecting them to rattle onto 500 or so. But let's not try to predict the future; our model may not be perfectly accurate (we don't expect it to be!) but it does help us get a rough idea of ranges of potential outcomes and in doing so deters us from trying to construct a narrative in advance (ahem, Vaughan, Hussain et al.). It's great once in a while when you get it right, but generally a waste of time (unless we're talking about Australia in the early 2000s).

So here's a summary of how much the players have done so far for their teams' chances of winning the Test:


Eng win
SL win
draw
Tremlett -4.7% -1.7% 6.5%
Morgan 8.3% -9.9% 1.5%
Strauss -6.2% 8.5% -2.3%
Finn -2.4% 4.0% -1.6%
Trott -7.1% 9.2% -2.2%
Cook 10.2% -11.7% 1.5%
Bell 1.4% -1.2% -0.2%
Pietersen -9.9% 10.7% -0.7%
Broad -6.6% 1.1% 5.5%
Prior 16.8% -20.2% 3.5%
Swann -15.7% 9.9% 5.7%

SL win
Eng win
draw
Maharoof -13.4% 10.2% 3.2%
Weleg'ara 3.2% 0.0% -3.2%
Dilshan 12.2% -23.4% 11.1%
Sang'ara 1.6% -3.5% 1.9%
Parav'ana 0.6% -5.2% 4.6%
Herath -9.3% 7.3% 2.1%
Fernando -6.1% 6.1% 0.0%
Lakmal 4.3% -1.1% -3.2%
P.Jay'dene 1.6% -1.5% -0.1%

Dilshan's superb effort has so far taken almost a quarter of a win away from England. Moreover, it has caused us to forget completely Matt Prior's excellent 126 off 131 balls (worth 16.8% of an England win) which had put England in a commanding position early on day 2.

Let's have a look at the Test so far, in graphical format:


Saturday, 4 June 2011

England v Sri Lanka, 2nd Test at Lord's: Day 1

Hello and apologies for the late update on Day 1's play at Lord's. As we're a bit behind, there's not much introduction needed (I suspect you're all in the park listening to TMS right now anyway): in summary, after a shaky start, a few tasty half centuries from Cook and the lower middle order brought calm back to the England hotel overnight.

Let's have a look at which players did the most to earn wins/losses/draws for their team:

Eng win
SL win
draw
Morgan 8.3% -9.9% 1.5%
Strauss -6.2% 8.5% -2.3%
Trott -7.1% 9.2% -2.2%
Cook 10.2% -11.7% 1.5%
Bell 1.4% -1.2% -0.2%
Pietersen -7.2% 9.0% -1.8%
Broad 2.9% -3.6% 0.7%
Prior 13.1% -17.0% 3.9%

SL win
Eng win
draw
Maharoof -13.4% 10.2% 3.2%
Wel'dara 3.8% -2.1% -1.7%
Dilshan -7.2% 5.5% 1.7%
Herath -11.7% 8.6% 3.1%
Fernando -2.5% 3.4% -0.9%
Lakmal 12.4% -8.0% -4.4%
P.Jay'dene -0.6% 0.6% 0.1%

Cook and Prior were England's standout players on Day 1. Cook remained calm as three quick wickets fell early in the day; his impressive knock of 96 was worth 10.2 % of a win for England. Prior's rapid knock of 73 left him unbeaten at the close of play with 13.1% of a win to his name. He has also done more than Cook to take the game away from Sri Lanka, lowering their chance of victory by 17 %. Lakmal's three top order scalps made him the early WPA front runner on the Sri Lankan team; his effort was worth 12.4 % of a Sri Lanka win.

Here's a graph of the game's progress as of the Day 1 close of play: