Alan Accountant and Edwina Economist are advising their friend Gerry Gameplayer who is going to play in the World Championship of ‘Scissors, Paper, Rock’. Gerry will be playing a sequence of games...

Alan Accountant and Edwina Economist are advising their friend Gerry Gameplayer who is going to play in the World Championship of ‘Scissors, Paper, Rock’. Gerry will be playing a sequence of games against each opponent in the contest. Edwina Economist says: ‘My advice is to choose randomly between the three strategies in each game you play’. Alan Accountant disagrees. He says: ‘If you choose randomly you will only have a one-third chance of winning each game. But I have a better strategy. No-one ever makes the same choice two games in a row. So I advise you in each game to choose the best response to one of the two strategies that your opponent did not choose in the last game. That way you will always have at least a one-half chance of winning each game’. Who do you believe is correct, Edwina or Alan? Explain your answer.