Automatically declaring the third innings when the lead is 300 – Analysis

One of the benefits of twitter is hearing new ideas. Jonas (@cric_analytics) has suggested the third innings should pause when the lead reaches 300, then the fourth innings takes place.

That way, a team that’s winning doesn’t have to pointlessly bat until the lead is over 500, before crushing an inferior opponent. Here’s how Jonas puts it:

I’ve modelled how this would work in practice, with the aim of answering two questions:

  • Does this make the strong team more likely to win? (Probably)
  • Is the game over sooner? (Generally)

Here’s the summary from the single scenario I looked at:

Scenario: West Indies vs England, Bridgetown.

England have batted first and scored 360. West Indies slipped up and were bowled out for 210. We join the action at the lunch on day three. England lead by 150. Two versions of this were modelled: under the existing laws, and temporarily declaring the third innings if they score 150 more.

Let’s see what happens:

  • In 92% of cases England made it to 150 without being bowled out – and so, with a lead of 300, temporarily declared
  • West Indies scored under 300 83% of the time – so the third innings did not need to re-commence
  • When the West Indies scored more than 300, sometimes the game meandered to a bore draw because the West Indies couldn’t confidently declare

Here’s the distribution of match end times depending on which rules apply:

We can see that there’s a big shift towards Day 4 finishes under compulsory declaration at 300 – mainly from the team batting fourth being bowled out for less than 300.

Worth noting the result wasn’t significantly affected by the rules being used. This would be different in other scenarios – such as if there was less time in the game.

Conclusion – This could be very useful in county cricket (where matches are only 4 days long). Suggest more modelling is required (especially scenarios where the odds are shifted from the draw being favourite to a result being favourite). A trial in County Championship Division 2 would be fascinating.