Quantifying Errors

Question 1

what is unbiased variance?

Answer 1

s^2 = 1/n-1 x sumofsquares

Question 2

what is standard deviation?

Answer 2

sd = root s^2

a quantity expressing by how much the members of a group differ from the mean value for the group.

Question 3

what is standard error?

Answer 3

se = sd/rootn
the se is the standard deviation of the sample mean, used to indicate uncertainty around the same mean estimate of the population mean

as n increases, se decreases

Question 4

what is the 95% confidence interval?

Answer 4

CI0.95 = 1.96xse

the probability that a value falls within the interval between -1.96 and 1.96 on the x-axis is 95%