STATS 250 Lecture 12: Chapter 7

• School: U of M
• Department: Statistics
• Course: STATS 250
• Professor: Alicia Romero

Document Summary

Want to learn about population mean . Use random sample to find sample mean to estimate the parameter. Sample mean may not be equal to parameter, could change every time a new random sample is taken. Statistic will have a probability distribution sampling distribution of the statistic. Sampling distribution of sample mean will be used to construct a confidence interval estimate for population mean and test hypotheses about value of population mean. Average of all sample means = population mean. Standard deviation of : population standard deviation divided by : : sample mean is an unbiased estimator of the population mean. If the parent population has a normal distribution, then the sample distribution is normal: size of sa(cid:373)ple does(cid:374)"t (cid:373)atter. Standard deviation of sample mean: s. d: how far apart a sample mean and the true population mean are expected to be on average. Interpretation approximately the average distance of possible sample mean values from the true population mean.