Poissonsarja

Poissonsarja is a Finnish term that translates to "Poisson series" or "Poisson sequence." It generally refers to a series or sequence of events or observations that follow a Poisson distribution. A Poisson distribution is a discrete probability distribution that expresses the probability of a given number of events occurring in a fixed interval of time or space if these events occur with a known constant average rate and independently of the time since the last event.

In statistical analysis, a Poissonsarja would be used to model phenomena where events are rare but occur independently. Examples include the number of phone calls received by a call center per hour, the number of defects found in a manufactured product per meter, or the number of radioactive decays per second. The key characteristic is the randomness and independence of the events within the specified interval.

The parameter associated with a Poisson distribution is lambda (λ), which represents the average rate of events in the given interval. The probability mass function for a Poisson distribution is given by P(X=k) = (λ^k * e^-λ) / k!, where P(X=k) is the probability of observing exactly k events, λ is the average rate, e is the base of the natural logarithm, and k! is the factorial of k. Analyzing a Poissonsarja involves understanding these probabilities and using them to make inferences or predictions about future occurrences.