Bernoulli distribution, binomial distribution, conceptual analysis

Bernoulli distribution

The Bernoulli distribution is a special case of the binomial distribution, which describes the probability distribution of only two outcomes in a single random experiment. where the probability of one outcome is ppp , the probability of another outcome is1 − p 1-p1p . The probability mass function of the Bernoulli distribution is as follows:

f ( k ; p ) = { p if  k = 1 , 1 − p if  k = 0. f(k;p)=\begin{cases} p & \text{if }k=1,\\ 1-p & \text{if }k=0. \end{cases} f(k;p)={ p1pif k=1,if k=0.

Among them, kkk represents the outcome of the event,ppp represents the probability of an event occurring.

A classic example of a Bernoulli distribution is a coin toss. In the process of tossing a coin, the probability of heads is ppp , the probability of tails is1 − p 1-p1p . ppherep is the parameter of the Bernoulli distribution.

binomial distribution

The binomial distribution is a kind of discrete probability distribution, which describes the nnIn n independent repeated random trials, an event occurskkThe probability distribution of k times. There are only two outcomes for each trial, success and failure. where the probability of success isppp , the probability of failure is1 − p 1-p1p . The probability mass function of the binomial distribution is as follows:

f ( k ; n , p ) = Pr ⁡ ( k ; n , p ) = Pr ⁡ ( X = k ) = ( nk ) pk ( 1 − p ) n − k , f(k;n,p)=\ Pr(k;n,p)=\Pr(X=k)=\binom{n}{k}p^k(1-p)^{nk},f(k;n,p)=Pr ( k ;n,p)=Pr ( X=k)=(kn)pk(1p)nk,

Among them, kkk represents the number of times the event occurred,nnn represents the total number of trials,ppp represents the probability of success for each trial.

A classic example of the binomial distribution is coin tossing. If we flip a coin once, then its outcome is a Bernoulli distribution. If we throw nn consecutivelyn times the coin, then its result is a binomial distribution.

Discrimination between Bernoulli distribution and binomial distribution

The Bernoulli distribution is a special case of the binomial distribution, n = 1 n=1n=1 situation. Therefore, the binomial distribution is a superposition of multiple Bernoulli distributions. In practical applications, the Bernoulli distribution is usually used to describe the results of a single trial, while the binomial distribution is usually used to describe the results of multiple trials. For example, we can use the Bernoulli distribution to describe the outcome of a coin toss, and the binomial distribution to describe the outcome of tossesnn times coin, heads upkkThe result of k times.

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Origin blog.csdn.net/qq_34022877/article/details/129559831