释义 |
confidence interval (confidence level) An interval, calculated from a sample, which contains the value of a certain population parameter with a specified probability. The end-points of the interval are the confidence limits. The specified probability is called the confidence level. An arbitrary but commonly used confidence level is 95%, which means that there is a one-in-twenty chance that the interval does not contain the true value of the parameter. For example, if is the mean of a sample of n observations taken from a population with a normal distribution with a known standard deviation σ, then

is a 95% confidence interval for the population mean μ. |