the frequency is the number of times each score, event or measurement occurs.

frequency distribution is shown in a table in which information or data is arranged in order. data can be individual or grouped into classes or intervals.

from the frequency distribution, the data can be shown on graphs such as bar graphs, histograms, frequency polygons and cumulative frequency graphs.

information about the spread of a set of results can be found from a cumulative frequency graph.

Key Skills

  • make a frequency table from a set of data
  • draw a bar graph, histogram, frequency polygon or cumulative frequency graph from a frequency table
  • read information from one of the above types of graph
  • calculate the mode, mean or median from a frequency table


ungrouped data, grouped dataaveragemedianmodemean, histogram, frequency curvefrequency polygon, discrete data, continuous data, cumulative frequencyupper quartilelower quartilepercentile