Choosing Distributions When should I use a Poisson distribution? A random variable that follows a Poisson distribution is a discrete random variable A Poisson distribution is used when the random v...
Continuous Uniform Distribution What is meant by the continuous uniform distribution? This is a special case of a probability density function for a continuous random variable The normal distributi...
E(X) & Var(X) (Continuous) What are E(X) and Var(X)? E(X)is the expected value, or mean, of a random variable X E(X) is the same as the population mean so can also be denoted by µ Var (X) is th...
Calculating Probabilities using PDF What is a probability density function (p.d.f.)? For a continuous random variable , it is often possible to model probabilities using a function This function is...
三大国际课程体系内AP，ALEVEL，IB课程中，IB体系无疑是全球公认最难的国际课程体系之一，所以选课就尤为重要了，特别是在进入IBDP阶段。选课这关没把好，会直接影响到IB大考的分数和申请结果。那么申英VS申美，I...
aX+b How are the mean and variance of X related to the mean and variance of aX + b? If a and b are constants then the following results are true E(aX + b) = aE(X) + b Var(aX + b) = a² Var(X) Note t...
Properties of Poisson Distribution What is a Poisson distribution? A Poisson distribution is a discrete probability distribution What are the important properties of a Poisson distribution? The mea...
Confidence Interval for μ What is a confidence interval? It is impossible to find the exact value of a population parameter when taking a sample The best we can do is find an interval for which the...
Sample Mean Distribution What is the distribution of the sample means? For any given population it can often be difficult or impractical to find the true value of the population mean, µ The populat...
