Скачать или смотреть How to calculate sample variance and standard deviation in excel

This video describes how to calculate sample variance and standard deviation using Excel, using two different methods.

This video corresponds to the information presented in Chapter 4 (variability) of Gravetter & Wallnau.

Video outline:
Step-by-Step calculations
-Start with calculating Sigma X (i.e., sum of X), you can divide this by N (i.e., the number of scores) to get the mean or use the “Average” function
-Make a column representing X-M, use the formula function to calculate each deviation score (X-M)
-Calculate the sum of the deviation scores to check your work, these should always add up to zero (or a value VERY close to it)
-Create a column for the squared deviation scores (X-M)^2, use a formula to do this, you can just type the first one (e.g. =c2*c2) and then click the box at the bottom of the cell (turns the cursor into a cross) and drag it down
-Add up all of the squared deviation scores to find the SS (i.e., Sum of the Squared deviation scores)
-Calculate variance (s^2) using df (i.e., n-1)
-Calculate standard deviation (s) by taking the square root of the variance

Using the excel functions for each (=VAR.S and =STDEV.S) to calculate sample variance and standard deviation.