First 155 words of the document:
Geographical skills theory
Frequency diagrams are useful to plot the distribution of values in your data set.
It gives a good visual impression of whether the two data sets are different and
allows the frequencies to be compared.
To make a comparison more quantitative key terms such as skew are used to
describe the distribution of data. Data is skewed if the distribution isn't
symmetrical. If the mode is lower than the mean it is said to be negatively skewed
and if it is higher than the mean then it is positively skewed.
Kurtosis is also used to describe distribution of data and this describes the
amplitude of the data or its shape. Distributions can be peaked, flat or in
Normal distribution is when the data forms a symmetrical curve in a frequency
graph around the mean.