Standard Deviation

 

I am almost positive that everyone in our class knows how to do standard deviation, but I know how to use it to solve other things.

            Standard deviation can help you find the answer to certain patterns in problems and you can find other things such as:  how to find x and y energies which ties into other things you can do like distribution.  Let’s say you were given a set of numbers that you got from some experiment you were doing and needed to find the standard deviation of the set of data you have, ok, what you do is take those numbers add them up and then divide them by the amount of numbers you added together.  For example:               

  1. First step

1

2

3

4

5

The sum of these numbers= 15.

            Now that you know the sum of your data you divide your answer by how many numbers you added up to begin with, in this case you would divide by 5.  Example:

  1. Second step

We have found the mean, which is 3 basically all we did was find the average of our data.

            Since we have our mean we now want to find the difference between each number we used to find the mean and the mean.  (Note that if your answer comes out negative just take the absolute value, which means to make it positive).  Example:

  1. Third step

2-3=-1=1

3-3=0

4-3=1

5-3=2

            After we’ve found this we now square these numbers, which means to multiply them by themselves.  Example:

  1. Fourth step

1*1=1

0*0=0

1*1=1

2*2=4

Last but not least we add the numbers up and divide them by the amount of numbers we had to begin with, then find the square root.  Example:

  1. Fifth step

1+0+1+2=4

now divide by 5

4/5=.8=sqrt.=.89.