# Difference between excel skew and calculated skew

Hi I have calculated skewness for a couple of data sets and find there is a discrepancy between my calculated skewness (sample) and that calculated using the excel sample skewness function skew().

In this exercise: Descriptive Statistics Fundamentals: Assignment: Skewness, Task 1

I calculated a skew of 0.569 and excel calculates 0.631

What is the cause of this difference? For reference I used the formula found at the start of the respective video lesson.

Hello everybody.

I have the same problem.

Somebody can reply?

I found solution!

That problem occurs because Excel use an another type of formula:

Excel offers the following built-in function to calculate the skewness of a distribution: **=SKEW(array of values)**

This function uses the following formula to calculate skewness:

Skewness = [n/(n-1)(n-2)] * Σ[(x_{i}–x)/s]^{3}

where:

n = sample size

Σ = fancy symbol that means “sum”

x_{i}= the value of the i^{th} value in the dataset

x = mean

s = standard deviation