Margin of error also referred to as confidence interval refers to the amount of. N is the minimum sample size Z is the value of the distribution function for normal distribution Z196 for alpha 005 s is the population standard deviation and d is the acceptable standard error of the mean the standard error of the mean is usually estimated as the sample standard deviation divided by the square root of the sample size. The standard deviation of a sampling distribution is called the standard error.
Find the sample mean.
To calculate a CI for the population mean average under these conditions do the following. Refer to the preceding t-table. Population Mean is required in order to predict the outcome from the entire data set. Margin of error also referred to as confidence interval refers to the amount of.