Lesson 10.3 - McGraw Hill Algebra I

Quartiles

Values that divide a data set into four equal parts

Measure of Position

A divide data set arranged in ascending order into four groups or 25% of the data.

Outlier

A value much greater or much less than the others in a data set

Standard Deviation (SD)

measures the average difference between each score and the mean of the data set

Five Number Summary

minimum, 1st quartile, median, 3rd quartile, maximum

Interquartile Range (IQR)

the difference between the first and third quartiles

Range

the difference between the highest and lowest scores in a distribution

Variance

the square of the standard deviation

Measures of Spread or Variation

Range, Interquartile Range, Standard Deviation

Lower Quartile (Q1)

The median of the lower half of a set of data; also called first quartile.

Upper Quartile (Q3)

The median of the upper half of a set of data.