Provide measures of variability (spread) of scores, includes the range and standard deviation.
What is the range?
Calculated by subtracting the lowest value from the highest value.
What is standard deviation?
The spread of data around the mean.
What does a higher standard deviation mean?
A wide spread suggests that not all participants were affected by the IV in the sameway, the results are less reliable and there may be anomalous results.
What does a lower standard deviation mean?
A narrow spread means participants were affected in a similar way and the results are more reliable.