POS 3713 Lecture Notes - Lecture 13: Central Limit Theorem, Statistic, True Value
Document Summary
Symmetrical represents the standard deviation of possible sample statistics. (15) The normal distribution allows us to make probabilistic statements about our sample statistic relative to the population parameter. aka standard error of the mean. There is a 95% chance that our sample statistic is plus or minus 2x(std error) from the population parameter. Most of the time, our sample mean is near the true value. All of the samples we could draw if the population equaled 50, shown in graph. Less than 5% chance of getting a sample = 49 if the true value is less than 39, or greater than 59. Interpreting standard deviations in the normal distribution. (28) The central limit theorem in action: take random sample, calculate sample mean, take new sample, calculate sample mean, repeat steps 1-4 an infinite number of times, plot sample means. Sample means will be normally distributed no matter how a variable is distributed in a population.
