# How to find the standard deviation If the standard deviation were zero, then all men would be exactly 70 inches (177.8 cm) tall. If the standard deviation were 20 inches (50.8 cm), then men would have much more variable heights, with a typical range of about 50–90 inches (127–228.6 cm). This is a tutorial on how to calculate the range and the standard deviation for statistics problem. This is a tutorial on how to calculate the range and the standard deviation for statistics problem. Standard deviation is a measure of spread of numbers in a set of data from its mean value. Use our online standard deviation calculator to find the mean, variance and arithmetic standard deviation of the given numbers. Read and learn for free about the following article: Calculating standard deviation step by step The standard deviation of an observation variable is the square root of its variance. Problem. Find the standard deviation of the eruption duration in the data set faithful. Solution. We apply the sd function to compute the standard deviation of eruptions. This video is unavailable. Watch Queue Queue. Watch Queue Queue If A is a vector of observations, then the standard deviation is a scalar. If A is a matrix whose columns are random variables and whose rows are observations, then S is a row vector containing the standard deviations corresponding to each column. If A is a multidimensional array, then std(A) operates along the first array dimension whose size does not equal 1, treating the elements as vectors. Standard Deviation Formulas. Deviation just means how far from the normal. Standard Deviation. The Standard Deviation is a measure of how spread out numbers are. You might like to read this simpler page on Standard Deviation first. But here we explain the formulas. The symbol for Standard Deviation is σ (the Greek letter sigma). In statistics, Bessel's correction is the use of n − 1 instead of n in the formula for the sample variance and sample standard deviation, where n is the number of observations in a sample.This method corrects the bias in the estimation of the population variance. It also partially corrects the bias in the estimation of the population standard deviation. Standard Deviation and Variance. Deviation just means how far from the normal. Standard Deviation. The Standard Deviation is a measure of how spread out numbers are.