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Only in certain circumstances:

The probability of success, p, in each trial must be close to 0.

Then, for the random variable, X = number of successes in n trials, the mean is np

and the variance is np(1-p). But since p is close to 0, (1-p) is close to 1 and so np(1-p) is close to np.

That is, the mean of the distribution is close to its variance. This is a characteristic of the Poisson distribution.

Furthermore, the other characteristics of the distribution: constant probability, independence are met so the Binomial can be approximated by the Poisson.

It is possible to prove this analytically but the limitations of this browser - especially in terms of mathematical notation - preclude that.

Only in certain circumstances:

The probability of success, p, in each trial must be close to 0.

Then, for the random variable, X = number of successes in n trials, the mean is np

and the variance is np(1-p). But since p is close to 0, (1-p) is close to 1 and so np(1-p) is close to np.

That is, the mean of the distribution is close to its variance. This is a characteristic of the Poisson distribution.

Furthermore, the other characteristics of the distribution: constant probability, independence are met so the Binomial can be approximated by the Poisson.

It is possible to prove this analytically but the limitations of this browser - especially in terms of mathematical notation - preclude that.

Only in certain circumstances:

The probability of success, p, in each trial must be close to 0.

Then, for the random variable, X = number of successes in n trials, the mean is np

and the variance is np(1-p). But since p is close to 0, (1-p) is close to 1 and so np(1-p) is close to np.

That is, the mean of the distribution is close to its variance. This is a characteristic of the Poisson distribution.

Furthermore, the other characteristics of the distribution: constant probability, independence are met so the Binomial can be approximated by the Poisson.

It is possible to prove this analytically but the limitations of this browser - especially in terms of mathematical notation - preclude that.

Only in certain circumstances:

The probability of success, p, in each trial must be close to 0.

Then, for the random variable, X = number of successes in n trials, the mean is np

and the variance is np(1-p). But since p is close to 0, (1-p) is close to 1 and so np(1-p) is close to np.

That is, the mean of the distribution is close to its variance. This is a characteristic of the Poisson distribution.

Furthermore, the other characteristics of the distribution: constant probability, independence are met so the Binomial can be approximated by the Poisson.

It is possible to prove this analytically but the limitations of this browser - especially in terms of mathematical notation - preclude that.

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10y ago

Only in certain circumstances:

The probability of success, p, in each trial must be close to 0.

Then, for the random variable, X = number of successes in n trials, the mean is np

and the variance is np(1-p). But since p is close to 0, (1-p) is close to 1 and so np(1-p) is close to np.

That is, the mean of the distribution is close to its variance. This is a characteristic of the Poisson distribution.

Furthermore, the other characteristics of the distribution: constant probability, independence are met so the Binomial can be approximated by the Poisson.

It is possible to prove this analytically but the limitations of this browser - especially in terms of mathematical notation - preclude that.

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Q: Why binomial distribution can be approximated by Poisson distribution?
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What is the difference between poisson and binomial distribution?

Poisson and Binomial both the distribution are used for defining discrete events.You can tell that Poisson distribution is a subset of Binomial distribution. Binomial is the most preliminary distribution to encounter probability and statistical problems. On the other hand when any event occurs with a fixed time interval and having a fixed average rate then it is Poisson distribution.


What kind of distributions are the binomial and poisson distribution?

Discrete


How many experimental outcomes are possible for the binomial and the Poisson distributions?

The binomial distribution is a discrete probability distribution. The number of possible outcomes depends on the number of possible successes in a given trial. For the Poisson distribution there are Infinitely many.


How do you differentiate a Poisson distribution and a binomial one in a level qns?

The Poisson distribution is characterised by a rate (over time or space) of an event occurring. In a binomial distribution the probability is that of a single event (outcome) occurring in a repeated set of trials.


State a condition under which the binomial distribution can be approximated by poisson distribution?

Because "n" is very large and "p" is very small. where "n'' indicates the fixed number of item. And ''p'' indicates the fixed number of probability from trial to trial.


What is the Assumptions for a Binomial distribution and Poisson?

For the binomial, it is independent trials and a constant probability of success in each trial.For the Poisson, it is that the probability of an event occurring in an interval (time or space) being constant and independent.


How can you approximate a binomial distribution to a poison distribution when the number of binomial trials became large enough?

The Poisson distribution with parameter np will be a good approximation for the binomial distribution with parameters n and p when n is large and p is small. For more details See related link below


When can a binomial situation be approxiamted with a normal distribution?

The binomial distribution can be approximated with a normal distribution when np > 5 and np(1-p) > 5 where p is the proportion (probability) of success of an event and n is the total number of independent trials.


How is poisson distribution related to binomial distribution?

If X and Y are i.i.d Poisson variables with lambda1 and lambda2 then, P (X = x | X + Y = n) ~ Bin(n, p) where p = lambda1 / lambda1 + lambda2


Which distribution is used to find probabilities about the number of independent events occurring in a fixed time period with a known average rate?

The Poisson distribution. The Poisson distribution. The Poisson distribution. The Poisson distribution.


Name of the very famous distribution that describes the frequency of the number of times a number comes up in a series of dice rolls?

The binomial distribution which, for large numbers of rolls can be approximated by the Gaussian distribution.


What is a frequency distribution defined by its average and standard deviation?

The triangular, uniform, binomial, Poisson, geometric, exponential and Gaussian distributions are some that can be so defined. In fact, the Poisson and exponential need only the mean.