Without sampling and statistical estimation of the value, some population parameters cannot ever be known. Take customer preference samples, for instance. Since asking everyone would be impractical, choose a sample to identify the parameter.
A population's mean can be estimated quite well using the confidence interval. It offers a spectrum of values that most likely includes the population mean. The interval gets smaller as sample size increases.
The method of ordinary least squares is used in a regression equation to develop an equation that best fits the data of an independent variable and dependent variable.
