Interpretations of a mixed strategy
1. The player tosses a (weighted) coin in order to choose the strategy to be played.
2. The player J is playing against a population of opponents. One part of the population of opponents always plays L, the other proportion of the population always plays R. The proportions are such that J is indifferent between the pure strategy of L and the pure strategy of R.
3. The players always use a pure strategy, but the payoffs from a strategic pair <LJay, RKay> are uncertain; payoffs are stochastic.
4. One or more players have a trembling hand. That is, sometimes you know the strategy you mean to play, but make a mistake when it is time to implement.