# Bernoulli Distribution

The Bernoulli distribution has an outcome space of two events {0, 1}, one of which happens with probability 1-p and the other which happens with probability p.&#x20;

$$
P(X=x) =\begin{cases}1-p,\&x=1\p, \&x=0\0, \&x\not=0,1\end{cases}
$$

A real-world system this distribution can model is a coin flip. Here, the two outcomes are heads (represented by 1) and tails (represented by 0). If the coin is fair, then p = 0.5.&#x20;

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Which of the following can be reasonably modeled by the Bernoulli distribution?

(a) Rolling a 6-sided die

(b) Passing or failing your driver test

(c) The weather tomorrow
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(b) is the correct answer because the outcome of a driving test is always either a pass or a fail.\
\
(a) and (c) both have outcome spaces that have more than two events in them; the die has six outcomes and the weather can be sunny, rainy, cloudy, snowy, etc. The Bernoulli distribution is not a good fit for these systems.&#x20;
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