A statistical tool that determines characteristics of a theoretical distribution formed by calculating the means of multiple samples drawn from the same population. This instrument provides insights into the expected behavior of sample means. For example, if a researcher repeatedly draws samples from a population and calculates the average of each sample, this tool allows the prediction of the distribution formed by those averages. This prediction includes the mean and standard deviation of that distribution.
Understanding the characteristics of sample mean distributions is fundamental to inferential statistics. It allows researchers to make inferences about population parameters based on sample data. Its importance stems from enabling hypothesis testing and the construction of confidence intervals, both essential for evidence-based decision-making in various fields. Early development of statistical theory laid the groundwork for this, with advancements in understanding probability distributions playing a crucial role.