Question

How do you find standard deviation once you know variance?

a. take the square root of variance

b. square variance

c. they are the same

d.Variance minus 1 equals standard deviation

This is the equation for population variance ______

a. Sum of Squares divided by N SS/N

b. Sum of Squares divided by N plus one SS/N+1

c. Sum of Squares divided by N minus one SS/N-1

d. It is the same for sample variance

You would use this equation to find variability for a sample _________

a. It is the same as the population variance

b. Sum of Squares divided by N SS/N

c. Sum of Squares divided by N minus one SS/N-1

d. Sum of Squares divided by N plus one

SS/N+1

Answer 1

ANS 1) a) take the square root of variance i.e.$standard deviation(s.d.)= \sqrt{variance}$

ANS2 ) a) sum of square divided by N ie SS/N or $variance = 1/N(x_{i}-xbar )^{2 }$

ANS3) c) variance of a sample is given by Sum of Square by N minus 1 i.e SS/N-1 or $variance = [1/(N-1)](x_{i}-xbar )^{2 }$