Standard Deviation

Question 1

What are the steps to calculating standard deviation?

Answer 1

1. add up the data and find the mean
2. (data - mean)
3. (data - mean) squared
4. add up the column of (data - mean) squared to get the variance
5. To get the standard deviation square root the variance and divide by the number of data -1

Question 2

How do you work out the variance?

Answer 2

The sum of (data - mean) squared

Question 3

What does it mean when the standard deviation is smaller than the variance?

Answer 3

The data is more distributed

Question 4

What are some examples of descriptive statistics?

Answer 4

mean
standard deviation
range

Question 5

What is the percentage within 1 standard deviation?

Answer 5

34% + 34% = 68%

Question 6

What is the percentage within 2 standard deviations?

Answer 6

95%

Because 34+34+13.5+13.5

Question 7

What is the percentage within 3 standard deviations?

Answer 7

99.7%