SE

SE, or Standard Error, is a statistical measure that indicates how much the sample average (mean) is likely to fluctuate from the true population average. It provides an estimate of the uncertainty or variability in the sample mean due to sampling randomness. A smaller SE suggests the sample mean is a more precise estimate of the population mean, while a larger SE indicates greater variability and less certainty. Essentially, SE helps us understand the reliability of the sample's average as an estimate of the true average in the larger population.