STA-1013 Lecture Notes - Lecture 5: Sample Size Determination, Sampling Distribution, Standard Deviation
Document Summary
Normal distribution- a symmetric, bell-shaped distribution with a single peak. Its peak corresponds to the mean, median, and mode of the distribution. Its variation can be characterized by the standard deviation of the distribution. Individual data values result from a combination of many different factors, such as genetic and environmental factors. The central limit theorem: population mean - , population standard deviation - , sample mean x bar, sample standard deviation - s, as sample size grows . Center: sample mean tends to gather closer to the population mean. Spread: the standard deviation of sampling distribution sample mean becomes smaller. Shape: bell-shaped: clt- the shape of the sampling distribution will become more like the shape of a. Normal distribution as n increases, regardless of population shape: the mean would be the same as the mean of population, the sd would be / n, conditions to assume that x bar is normally distributed.
