3.2 Measures of Dispersion
Discuss limitations of the range as a measure of dispersion.
The range only takes into account the smallest and largest values, which does not provide any information about the dispersion of the distribution between those values.
The sum of the deviations about the mean
always equals 0
Standard Deviation (SD)
measures the average difference between each score and the mean of the data set
When comparing two populations, the larger the standard deviation,
the more dispersion the distribution has.
True or False: When comparing two populations, the larger the standard deviation, the more dispersion the distribution has, provided that the variable of interest from the two populations has the same unit of measure.
True, because the standard deviation describes how far, on average, each observation is from the typical value. A larger standard deviation means that observations are more distant from the typical value, and therefore, more dispersed.