Bernoulli trial

A “Bernoulli trial” is a model of randomness in which there are two possible elementary outcomes in the sample space, with the probability of one outcome given by the model parameter \(p\) (and the probability of the other is then \(1-p\)).

The iconic example is that of a single toss of a coin. If the coin is fair, that is, equally likely to land with either of its two sides, typically designated “heads” or “tails”, then it can be modeled as a Bernoulli trial with parameter \(p = 0.5\) giving the probability of “heads”. Conversely, a trick coin may have the a “heads” on both sides, thus always landing with a “heads” result, an or a “tails”