This could be considered a subset of the more general problem of trying to figure out when two points on a graph are meaningfully different, as opposed to just

This could be considered a subset of the more general problem of trying to figure out when two points on a graph are meaningfully different, as opposed to just visually different. In my early physics training the importance of putting error bars on data points was stressed, allowing for a visual comparison of the difference between two points in standard deviations.