S W 318 Lecture 6: Chapter 8 - Estimation
Document Summary
A process whereby we select a random sample from a population and use a sample statistic to estimate a population parameter. A sample statistic used to estimate the exact value of a population parameter. A range of values defined by the confident level within which the population parameter is estimated to fall. The likelihood, expressed as a percentage of a probability, that a specified interval will contain the population parameter. Take a subset of the population -> calculation of sample mean and standard deviation -> inference about population -> sampling procedure. Variation in the larger group that we want to know. Variation in the sample that we can observe. A normal distribution whose mean and standard deviation are unbiased estimates of the parameters and allows one to infer the parameters from the statistics. Even if a population distribution is skewed, we know that the sampling distribution of the mean is normally distributed.