The first quartile, a measure of variability, based on dividing a data set into quartiles
Mode
The number which appears most often in a set of numbers
Mean absolute deviation
a dataset is the average distance between each data point and the mean
Mean
the average of a set of numbers
Range
The difference between the lowest and highest values
Random sampling
A selection that is chosen randomly
Representative sample
a group that closely matches the characteristics of its population as a whole
Interquartile Range
a measure of variability, based on dividing a data set into quartiles
Upper quartile
the median of the upper half of a data set. This is located by dividing the data set with the median and then dividing the upper half that remains with the median again, this median of the upper half being the upper quartile
Bias
the difference between this estimator's expected value and the true value of the parameter being estimated
