Statistics: What do they Mean?

Learner Profile can compile a variety of reporting statistics about scores and grades. Here’s a glossary of statistical terms:

• MEAN: Also called average, it’s the sum of a set of numbers divided by the number of elements in the set.



• MEDIAN: Like the mean, this statistic also measures the center of a set of data, but does so by finding the data point which divides the set in half.



• HIGH SCORE: The highest score in the set.



• LOW SCORE: The lowest score in the set.



• RANGE: The difference between the greatest number and the least number in a set of a numbers.



• VARIANCE: Tells how dispersed a set of data is. This number will always be equal to or greater than zero, with larger numbers describing a set of data that is more spread out.



• AVERAGE DEVIATION: The mean of the absolute values of all the deviations in a set of data. It tells by how much each data point differs from the mean—a low average deviation tells you that the data tend to cluster around the mean, a higher average deviation tells you that the data are more spread out.



• STANDARD DEVIATION: Another way to describe how data in a set tend to differ from the mean. Standard deviation is used to talk about data that have a normal distribution—that is, more data points in the middle and fewer on the ends. In a normal distribution, 68% of the data points should be no more than one standard deviation on either side of the mean.