# Does the Duckworth–Lewis method work correctly for all matches?

D/L method is commonly used for limited over matches. Does it work fine?

The opening players didn't know it would rain that day, so they defend to stand for 20 to 25 overs; then how is it correct for deciding the victory by this? Some teams may have aggressive players in the bottom order, so we can't judge by losing 6 or 7 wickets.

Some other teams mostly depend on one or more star players; if the bowling side tried hard to pick them at the last stage, then the D/L method will give the victory to the batting side.

Is this method the only choice for the cricket officials?

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If your question is if this system is fair, then my response is that it is highly criticized.

This method has been criticized based on the fact that wickets are (necessarily) a much more heavily weighted resource than overs. For winning a match if rain is interpreted the match, strategy could be to not lose wickets and score at what would seem to be a "losing rate. So teams could use this rule to win the game, which most teams have a strategy to do so.

Another criticism is that the duckworth-lewis method does not include the changes in the proportion of number of overs during which field restrictions are in place compared to a completed match.

The most common criticism is that this method is just down right too complicated to understand since it involves very heavy math.

This method is the only choice that officials have to calculate the score of a match that is interrupted by weather or other circumstances.

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I suppose the ideal system would have the property that it makes no tactical difference to either team whether it rains or not, whereas in fact the batting team does have different optimal tactics according to whether they think it will rain (and how long for). But calling it a draw wouldn't achieve that property either, since under that system a team expecting rain would do the opposite: play far more aggressively for a few wickets, hoping to score the runs before the rain. Just as a team might have a go in a test if it needed (say) 250 in 30 overs at the start of the fourth innings. –  Steve Jessop Jul 8 '14 at 10:56

D/L or any other method is necessarily an approximation, so there will always be some strange edge cases. But it's arguably better than not having any result at all.

Regarding your concerns of correctness. The D/L method is based on statistics from previous games, so it does generally take into account that teams have aggressive players in the lower middle order etc. Also, if there is an interruption during the first innings, the team batting second will normally get a higher target, exactly because of your concern: The team batting first did not know it was going to rain and was playing conservatively, but the team batting second does and can plan accordingly. That is pretty much the whole point of using the D/L method over more simplistic methods such as run-rate calculations.

There are alternative methods. The D/L method is currently used for all ICC limited overs matches and most high-profile national competitions. The VJD system is an alternative system that is claimed to be better but has currently not found any high-profile uptake. In amateur leagues you will probably find some kind of run-rate calculation in use, which is well-known to be flawed, but simpler to apply in such competitions. It depends on what the respective governing body decides.

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IIRC there are also separate D/L tables for different categories of match. So even with D/L there are in that sense "alternative methods". The tables for your category are more likely to reflect how the game plausibly might have gone absent the interruption, but no guarantees. –  Steve Jessop Jul 8 '14 at 10:52

The D/L method was designed with 50-over matches in mind. It came in for some criticism during the 2012 World Twenty20 when it was applied to some matches that were greatly reduced in duration due to rain. The team batting second was put at a great advantage as they were able to use all 10 wickets to pursue a D/L target that was only moderately above the original target in terms of runs per over. This article explains that this was because D/L method was applied as though a T20 match is the equivalent of the final 20 overs of an ODI, and recommends instead that it ought to be applied as though a T20 is a much faster version of a 50-over match.

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