standard deviation

Question 1

what is standard deviation?

Answer 1

• tells us how spread out the data is from the mean and gives us more information than just the average
• high SD = data very spread out from the mean

Question 2

how do you calculate standard deviation?

Answer 2

• calculate the mean
• subtract the mean from each value in the data set
• square each result from step 2
• calculate the mean of those squared differences but instead of dividing by the number of values, divide by THE NUMBER OF VALUES MINUS 1. (this gives the variance)
• square root the final number in step 4 to get standard deviation