]> The Ballot Experiment

The Ballot Experiment

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Description

The ballot experiment concerns an election in which candidate A receives a votes and candidate B receives b votes, where a b . The votes are assumed to be randomly ordered. The first graph shows the difference between the number of votes for A and the number of votes for B , as the votes are counted. This process is a random walk in which the initial and terminal points are fixed.

The event of interest is that A is always ahead of B in the vote count, or equivalently, that the graph is always above the horizontal axis (except of course at the origin). The indicator variable I of this event is recorded in the first table on each update. The probability density function of I is shown in blue in the distribution graph and is recorded in the distribution table. On each update, the empirical density function of I is shown as red in the distribution graph and recorded in the distribution table. The parameters a and b can be varied with scroll bars.