SOAN 3120 Chapter Notes - Chapter 15: Central Limit Theorem, Sampling Distribution

• School: University of Guelph
• Department: Sociology and Anthropology
• Course: SOAN 3120
• Professor: Andrew Hathaway

Document Summary

A parameter is a number that describes the population. In practice, the value of a parameter is not known because we can rarely examine the entire population. A statistic is a number that can be computed from the sample data without making use of any unknown parameters. In practice, we often use a statistic to estimate an unknown parameter. Remember, statistics comes from samples, and parameters come from populations. Now that we can beginning to understand what our data (sample) tell us about a population, the distinction between the two is essential: we write for the population mean and for the population standard deviation. These are fixed parameters that are unknown when we use a sample for inference: the sample mean is x and the sample standard deviation is s. Statistics that would almost certainly take different values if we chose another sample from the same population.