Dichotomous key for Biometry
1. The variable is discreet - 2
The variable is continuous - 4
2. The events are independant of each other or are assumed to be independant. You know the probability of success (p) and the sample size (k) - Binomial
You do not know the probability of success - 3
3. The events appear random in time or space, the events are independant of each other, or are assumed to be independant. You do not know the probability of success, p < 0.1 and kp < 5. You do know . - Poisson
4. You are trying to estimate the variance. - Chi Squared distribution
5. You are not trying to estimate the variance. You know and , the sample size is large or the study period is over several years. - Normal distribution - (z)
6. The sample size is small, you do not know and , but you can estimate them with ´ and s.
- t-distribution