Standard Deviation Flashcards
1
Q
What are the steps to calculating standard deviation?
A
- add up the data and find the mean
- (data - mean)
- (data - mean) squared
- add up the column of (data - mean) squared to get the variance
- To get the standard deviation square root the variance and divide by the number of data -1
2
Q
How do you work out the variance?
A
The sum of (data - mean) squared
3
Q
What does it mean when the standard deviation is smaller than the variance?
A
The data is more distributed
4
Q
What are some examples of descriptive statistics?
A
mean
standard deviation
range
5
Q
What is the percentage within 1 standard deviation?
A
34% + 34% = 68%
6
Q
What is the percentage within 2 standard deviations?
A
95%
Because 34+34+13.5+13.5
7
Q
What is the percentage within 3 standard deviations?
A
99.7%
