If algebra is your thing, feast your eyes on that. If not, do not despair. For the men behind it think their formula for working out targets in rain-affected games is understandable by all. A report in BBC News Online says it all.Frank Duckworth and Tony Lewis (no relation to the MCC president and former commentator) devised their system in an attempt to avoid a repeat of the semi-finals of the 1992 World Cup.
South Africa had fought back against England when a spell of rain saw their target of 22 runs from 13 balls change to 21 runs from just one ball. Not surprisingly, England won.
The Duckworth/Lewis scheme has now been adopted by most cricket-playing nations but is being used for the first time in the World Cup this year. Duckworth told BBC News Online it should not be beyond people.
``It's an important point that you don't need to be able to understand the algebra to understand how the system works,'' he explained.
The principle behind the scheme is that when rain stops play, the batting teamloses run-scoring ability rather than just a set number of balls or overs.
Overs and wickets
``That doesn't just depend on the number of overs that are lost. It depends on which overs are lost, and how many wickets have been taken,'' Duckworth explained.
So the system takes into account the fact that it is easier for a team to sustain a higher run rate over a 40 over-innings than 50.
And whether a team is cruising for the loss of two or three wickets, or struggling with eight down is also worked into the formula.
So, deep breath, here goes. Here is a typical match example plus the summary of the system, as published by Lord's.
(And if you do not understand this, then just hope the sun keeps shining until 20 June.)
Example:
Team 1 are all out for 160 after 38 overs in a match reduced to 40 overs per side before its start. The start of Team 2's innings is delayed by rain and they are allocated only 30 overs. Team 1 had 40 overs available (the fact that they were allout before they were used up is irrelevant) so the table tells us that they had 90.3 per cent resources (compared with a 50-over innings) available. Team 2 go out to bat with 30 overs allocated. The tables tell us that they have 77.1 per cent resources available. Team 2 have less resource than Team 1 and need to be set a reduced target. The calculation 160 x 77.1/90.3 gives 136.61, so team 2 are set a target of 137. Should further rain mean that more of the match is lost to rain, then the target can be changed any number of times according to the formula.Summary of the D/L method
The D/L method sets a revised target for the side batting second (Team 2) when overs have been lost by a suspension in play. The revision is not in proportion to the numbers of overs the two sides can receive but is in accordance with the run-scoring resources the two sides have at their disposal. These resources include both overs and wickets in combination. A single table gives theresources remaining at any stage of an innings for any number of overs left and wickets lost. The resources are expressed in terms of the percentages of the resources of a full 50-over innings. If either innings is shortened after it has started then the balance of resources of the two sides is upset and a revised target needs to be set in accordance with the resources available to the two sides. To find the resources available for either innings, you use the table to find out the resources lost from that innings and subtract this from the resources with which the innings started. If the innings started with 50 overs to be received, the resources at the start of the innings are 100 per cent. But if the innings is shortened before it starts, or if the match is of less than 50 overs per side, then the resources at the start are less than 100 per cent. To find the resources lost from an innings due to an interruption: (i) note the numbers of overs left and wickets lost at the start of thesuspension; use the table to find the resources remaining; (ii) note the same at the resumption of play and from the table read off the resources now remaining; (iii) subtract (ii) from (i) to give the resources lost. To find the resources available, subtract the resources lost from the resources that were available when the innings started. When a revised target has to be set, find the resources available for both sides and calculate the revised target as follows, always rounding down to a whole number. If the resources available to Team 2 (denote this by R2) are less than those for Team 1 (R1), then the target is revised downwards in proportion to the resources.Thus Team 2's revised target = Team 1's actual score x R2/RI, plus one run. (One run less than the target gives a tie.)
If the resources available to Team 2 are greater than those for Team 1, then Team 2's target must be revised upwards. The excess runs required are calculated by applying the excessresource to the average 50-over total of 225 (or whatever number is decided upon for the appropriate class of game).
Thus Team 2's revised target = Team 1's actual score - (R2 - RI) x 225/100, plus one run. (One run less than the target gives a tie.)
Copyright © 1999 Indian Express Newspapers (Bombay) Ltd.
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