descriptive statistics

Counting: how to find the number of elements of a list in Excel

The function that counts the number of numbers in a range of cells is represented as =count( A1:A9 ) or =count( A:A )

where A1 is the start and A9 is the end. obviously, there’s 9 elements in between them.

Summation: how to find the total sum of elements of a list in Excel

The function that calculates the sum of a list of numbers in a range of cells is represented as =sum( A1:A9 ) or =sum( A:A )

adds A1 + A2 + A3 + A4 + A5 + A6 + A7 + A8 + A9

Sum of squares: how to find the sum of the squares of each element of a list in Excel

The function that calculates the sum of the squares of a list of numbers in a range of cells is represented as =sumsq( A1:A9 ) or =sumsq( A:A )

adds A1² + A2² + A3² + A4² + A5² + A6² + A7² + A8² + A9²

this is useful for variation: sum of (each element²)

Cross summation: how to find the sum of (product between lists) in Excel

The function that calculates the sum of the products of corresponding values in two lists is represented as =sumproduct(A1:A9,B1:B9)

elements in [A1 to A9] is multiplied with elements in [B1 to B9] and then added up

this is useful for (find out what this is useful for: to do list!!1)

what does this symbol represent?

this symbol represents mean

also known as the average (how much is it in total divided by how many elements there are)