Learning objectives
Calculate the mean, median and mode and the range, interquartile range and standard deviation of raw data, and choose the measures best suited to a data set
Estimate the mean and standard deviation of grouped data using class mid-values
Find the mean and standard deviation from the totals Σx and Σx² using x̄ = Σx/n and σ² = Σx²/n − x̄²
Use coded totals Σ(x − a) and Σ(x − a)² to find the mean and standard deviation of x, recognising that subtracting a constant moves the mean but leaves the spread unchanged
Combine two data sets to find the mean and standard deviation of all the values together, and compare data sets in context using one measure of centre and one of spread
Continue with a revision plan
These learning objectives are available to everyone. Sign in with an eligible plan to read the full note and worked examples.