Question

Explain what the standard deviation is for a set of data.

Answer 1

Shows the variation in data(average of all means of the data)

Explanation:

Ok,so, if for example, data is grouped close together, then the standard deviation will be small, if the data is more spread out then the deviation will be larger. How to tell?

Well, it all depends on the distance away from the mean. The center is usally where the mean is. How far from the mean is your data?

How to calculate?

-There are multiple equations you can use depending on your data.

If you are analyzing data which represents a larger set, use sample standard deviation, if you collect data from every member of the set, then use population standard deviation.

First, calculate the mean(average) of each set of data.

Then subtract the deviance(subtract mean from each number -/+)

Square each deviation

add up all squared deviations

Divide the number by one less than the number of items in the data. (If it was 5 it would be 4.)

Then calculate the square root of the resting value.

Answer 2

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)