If I have an event like this:
"In mean I create 5 object every ten minute". I have to use the Poisson Distribution
http://en.wikipedia.org/wiki/Poisson_distribution:
I must determinate the parameter lambda. I think lambda is (temporalInterval / mean) that in this case is (10/5). is it correct? I don't know if this solution is correct. Anyone can help me?
Lambda is the rate of the observed process. Rates are of the form "count per unit". If your Poisson is being used to describe a temporal process, the rate is E[count / unit time] and an unbiased estimate of it is observed count / observed time. If you have observed 5 objects in 10 minutes, the estimated rate is 0.5 per minute. Poisson rates can be scaled to different time units if desired, so a rate of 0.5 per minute is also 5 per 10 minutes or 30 per hour. The choice of a useful unit of time is up to you, but make sure you use units consistently throughout a problem.
Lambda is not a probability, as stated by another respondent. That claim is trivially disproven since lambda can be any positive value, while probabilities must be numbers between zero and one.