Statistics

Question 1

How do you calculate the standard error of the mean?

Answer 1

Standard error of the mean (SEM) is an indicator of how the true mean of the population would differ from the mean of your sample

Standard error of the mean = SD / square root of (n)

SD = standard deviation
n = sample size

Question 2

What is the 95% confidence interval

Answer 2

The range of values within which you are 95% certain the true value lies within.

Question 3

How do you calculate the 95% confidence interval?

Answer 3

Upper limit = mean + (1.96 x SEM)
Lower limit = mean - (1.96 x SEM)

1.96 is the critical value

Note - often easier to change this to 2x SEM to make calculation easier