Bernoulli Distribution :
Bernoulli distribution is a probability distribution that describes the outcomes of a binary experiment, where there are only two possible outcomes: success or failure. In other words, it is a statistical model that describes the probability of an event occurring or not occurring. It is named after Jacob Bernoulli, who first introduced the concept in his book, Ars Conjectandi, in 1713.
The Bernoulli distribution is defined by the probability of success, denoted by p, and the probability of failure, denoted by 1-p. If p is the probability of success and q is the probability of failure, then the probability of any specific outcome is defined as:
P(X=x) = p^x * q^(1-x)
where X is a random variable representing the outcome of the binary experiment and x is the specific outcome (either 0 for failure or 1 for success).
For example, consider a coin toss experiment, where the probability of the coin landing on heads is 0.5. Using the Bernoulli distribution, we can calculate the probability of the coin landing on heads as:
P(X=1) = 0.5^1 * 0.5^(1-1) = 0.25
Similarly, we can calculate the probability of the coin landing on tails as:
P(X=0) = 0.5^0 * 0.5^(1-0) = 0.25
Thus, the Bernoulli distribution accurately describes the probabilities of the two possible outcomes in a binary experiment.
Another example of Bernoulli distribution is the probability of a customer purchasing a product from a store. Let’s say the probability of a customer purchasing the product is 0.7. Using the Bernoulli distribution, we can calculate the probability of a customer purchasing the product as:
P(X=1) = 0.7^1 * 0.3^(1-1) = 0.21
Similarly, we can calculate the probability of the customer not purchasing the product as:
P(X=0) = 0.7^0 * 0.3^(1-0) = 0.79
Thus, the Bernoulli distribution accurately describes the probabilities of the two possible outcomes in this binary experiment.
In general, the Bernoulli distribution is useful in situations where there are only two possible outcomes, such as in medical trials where the outcome is either success or failure, or in political polls where the outcome is either support or opposition. It is also used in machine learning algorithms to predict the probability of an event occurring or not occurring.
However, the Bernoulli distribution has some limitations. It assumes that the probability of success and failure is constant, which may not always be the case in real-world situations. It also assumes that the outcomes are independent, which means that the outcome of one event does not affect the outcome of another event. This assumption may not always hold true in complex situations.
Despite these limitations, the Bernoulli distribution is a widely used probability distribution that accurately describes the outcomes of binary experiments. It provides a simple and effective way to model and predict the probability of success and failure in a wide range of situations.