How to Calculate Standard Error of The Mean

The Standard Error of the Mean is a measurement of the error around the point estimate average of population. Statisticians use the Standard Error of the Mean to determine with confidence the range of values of the population average. This article will detail the steps to calculate that Standard Error of the Mean in as simplest terms as possible.

Things You'll Need

• Basic Math knowledge

Instructions

1. 

   Determine the population mean or average. The population mean is simply taking each sample and dividing it by a count of the number of samples in the population. The simplest method is to use the AVERAGE function in most spreadsheet programs.

2. 

   Calculate the standard deviation of the population. The standard deviation is a measurement of the dispersion of the samples of the population from the mean. Each unit of standard deviation is a likelihood that the sample population falls within that range. The standard deviation is usually labeled as S. The simplest way to calculate is using the STDEV function in most spreadsheet programs.

3. 

   Calculate the Standard Error of the Mean. The Standard Error of the Mean is the likelihood range of values of the Mean of the population. The Standard Error or otherwise SE of the mean is calculated by taking the Standard Deviation and dividing by the square root of the number of samples, n. The value of knowing the Standard Error of the Mean is determining with confidence what a range of values the Mean may reside.

4. 

   Given a 95% confidence we can conclude that an Upper Limit = Mean + SE*(1.96) and a Lower Limit = Mean - SE*(1.96)