DON’T know, don’t care. This was the overwhelming response from people in Bournemouth when asked about the alternative voting system.

On Thursday May 5 the public has been invited to trundle up to the polling station and put a cross in a box to decide whether to change the voting system used to decide who become our MPs.

The referendum will ask the public whether they want to replace the existing first-past-the-post system for electing MPs to Westminster with a method known as the alternative vote (AV).

But there is widespread concern that people will fail to show up because they don’t understand what AV is and don’t really care.

Paul West, 43, said: “I am not 100 per cent. When you have a next election there is a second choice so you don’t have a hung parliament.”

Laura Vuagnaux said: “I don’t know, I haven’t got a clue. It doesn’t interest me and I don’t know what it is about.”

Krista Green said: “No, I don’t know what it is. I am not really interested in the whole thing as I don’t really follow it. I don’t even follow the news, it depresses me.”

And Keith Hadfield said: “I do know what it is but I don’t know how to explain it. I have read all about it and I know why I should vote for AV as opposed to the one there is now.”

What is the choice?

AV (alternative vote)

This system sees voters rank candidates in order of preference. People can nominate as many or as few preferences as they like. Only first preference votes are counted initially.

Anyone getting more than 50 per cent of these is elected automatically. If that doesn’t happen, the candidate with the fewest votes is eliminated and their second choices allocated to the remaining candidates in a second round of voting.

This process continues until one candidate has 50 per cent or more of the vote. Critics say too many votes are wasted under the current system, with elections decided by a small number of voters in handful of seats where no single party has a large majority.

FIRST-PAST-THE-POST (winner takes all)

This is the current voting system for Westminster elections. Voters mark an x next to their preferred candidate. The candidate with the most number of votes in each constituency wins the seat.

Defenders of the current system say it generally leads to a stable government and has historically reflected the will of the public in that unpopular governments have been voted out.

This system favours large parties and works against smaller ones and means elections are decided only in marginal seats.