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Some Probability Distributions

Probabilities for a binomial random variable $ X$ are calculated using the commands dbinom and pbinom.

The probability of 3 successes in $ n=10$ trials with a success probability $ p=0.25$ is computed by

The command pbinom computed cumulative probabilities. The probability of three or fewer successes in $ n=10$ trials with a success probability of $ p=0.25$ is computed as
The functions dpois and ppois compute probabilities and cumulative probabilities for a Poisson distribution. The probability that a Poisson random variable with mean 0.5 equals ne is given by
The cumulative probability that a Poisson random variable with mean 0.5 is at most one is given by
Try some examples of your own in the work area below.

Work Area
Enter your own commands here; then click the Submit button.

next up previous
Link to Statistics and Actuarial Science main page
Next: The Distribution Up: Some Rweb Notes Previous: Examining Sampling Distributions
Luke Tierney 2006-08-23