Parameters are descriptive measures of an entire population that may be used as the inputs for a probability distribution function (PDF) to generate distribution curves. Parameters are usually signified by Greek letters to distinguish them from sample statistics. For example, the population mean is represented by the Greek letter mu (μ) and the population standard deviation by the Greek letter sigma (σ). Parameters are fixed constants, that is, they do not vary like variables. However, their values are usually unknown because it is infeasible to measure an entire population.
|Distribution||Parameter 1||Parameter 2||Parameter 3|
|Chi-square||Degrees of freedom|