Terms you'll find helpful in completing today's challenge are outlined below.
Expected Values
The expected value of a discrete random variable, , is more or less another way of referring to the mean (). We can also refer to this as the mathematical expectation (or just the expectation) of .
Variance
This is the average magnitude of fluctuations of from its expected value, . You can also think of it as the expectation of a random variable's squared deviation from its mean. Given a data set, , of size :
where is the element of the data set and is the mean of all the elements.
Standard Deviation
The standard deviation quantifies the amount of variation in a set of data values. Given a data set, , of size :
where is the element of the data set and is the mean of all the elements.