Duckworth-Lewis, What a relief !


Taken by myself, this morning, at the Sydney C...

(Photo credit: Wikipedia)

ICC World Cup 1992, 2nd Semi-final – England vs. South Africa, Sydney Cricket Ground (SCG). SCG was buzzing with capacity crowd. It was March 22 and when rain stopped play for the last time during this match, 22 (off 13 balls) were precisely the runs required for South Africa to make it to the World Cup final. South Africans didn’t know then, that, when play resumes they would be faced with their worst moment after a long 21 years exile from international cricket. When the play resumed, they did know. The large screen at SCG displayed, 22 REQUIRED OFF 1 BALL.

Cricket is primarily an outdoor sport and like any other outdoor sport, a possibility of it being interrupted by rain or bad weather is always on cards. For years, various rules have been applied to calculate targets in curtailed games. South Africans, at SCG, found themselves at receiving end of one such rule. The rule applied during this game was the “best scoring overs” rule. As per this rule, for the amount of time lost due to interruption, no. of overs that the side chasing gets to bat are reduced proportionately. And, the achievable target is arrived at by adding up runs scored in the ‘best scoring’ overs of the previous innings. So, let’s consider an over lasts for approximately four minutes, if 20 minutes are lost due to interruption, a team gets to bat five overs less and they would be chasing a target by including runs from five ‘best scoring’ overs of the first innings. Thus, in such a situation, if five maidens are bowled in the first innings, target for the team chasing remains unchanged, though they lose five overs. At SCG around 10 minutes were lost in that fateful semi-final. Well, some rule, but not quite.

Two English statisticians, Duckworth and Lewis, addressed this problem and provided a beautiful solution that is now being used in all modern day limited over cricket formats. It is scientific, mathematical, logical and thus widely acceptable. The core concept on which Duckworth-Lewis (D/L) method has its foundation is ‘available resources’. Resources in this context means remaining overs and wickets in hand. As per this rule, these two resources, more or less define a team’s chances of chasing down a target. Thus, at a given point of time, if a match has to be abandoned due to rain or any other reason, a potential victory or defeat is assumed to be based on wickets standing and overs remaining. D/L have nicely derived a table in which, if you input remaining overs and wickets in hand, you know how much is a team looking at.

For D/L to apply, a minimum of 20 overs in an ODI game and at least five overs in a T20 game should have been completed. A major criticism of D/L is, that via this rule, result of a game is driven more by wickets standing than by overs remaining, and thus that ‘balance’ between the ‘resources’ is missing. But isn’t it so much better than what we saw at SCG, ahh, such a relief !!! WW6PXY4QQTKV

Advertisements

Leave a Reply

Fill in your details below or click an icon to log in:

WordPress.com Logo

You are commenting using your WordPress.com account. Log Out / Change )

Twitter picture

You are commenting using your Twitter account. Log Out / Change )

Facebook photo

You are commenting using your Facebook account. Log Out / Change )

Google+ photo

You are commenting using your Google+ account. Log Out / Change )

Connecting to %s