Variability
Tut1 - SST
, Measures of Variability
Measures of central tendency (see Tutorial 3 of prescribed reading) tell us, in a
highly economical fashion, where the midpoint of a group of scores is, but they
do not reveal anything about the way the scores are arranged around that
midpoint. Measures of variation do exactly that – they tell us how widely
dispersed numbers are. There are three commonly used measures of variation –
range,
the variance, and the
standard deviation –
Each of which helps us to understand the degree of variability in a dataset in a
different way. Measures of variability indicate the degree to which the scores
are dispersed, or different from each other.
Tut1 - SST
, Measures of Variability
Measures of central tendency (see Tutorial 3 of prescribed reading) tell us, in a
highly economical fashion, where the midpoint of a group of scores is, but they
do not reveal anything about the way the scores are arranged around that
midpoint. Measures of variation do exactly that – they tell us how widely
dispersed numbers are. There are three commonly used measures of variation –
range,
the variance, and the
standard deviation –
Each of which helps us to understand the degree of variability in a dataset in a
different way. Measures of variability indicate the degree to which the scores
are dispersed, or different from each other.
