PSYCH 100A Chapter 8: Parameter Estimation
Document Summary
Fluctuates from sample to sample but the central limit theorem states that the values are normally distributed with mean and standard deviation (standard error) = . 95% of the time the sample mean will be within two standard errors of . The distance between the sample mean and the population mean is probably less than about two standard errors. Critical values of z: the value of a statistic that marks the boundary of a specified area (such as 0. 05 or 0. 01) in the tail of the distribution. We don"t know where the sample mean is but it is probably within about 2 standard errors of . Point estimate: a computed statistic that approximates a parameter. Sample mean is the best possible point estimate of the population average that can be obtained from a sample size n. Rarely exactly equal to the population parameter due to sampling fluctuations.
