Visualisation/Boxplot

The box plot summarises the statistics of the distribution of a variable (nutrient). This graph is especially suited for non-normal (non-gaussian) distributions. A typical bixplot contains the median, the mean, the quartiles, minimum/maximum and limits (lower/upper) of the distribution. Usually the X-axis lists one or more product sets, for instance products in a specific category. And the Y-axis shows the statistical parameters. The interquartile distance is drawn as a box. The limits as lines blow and above the box (the whiskers).

Enhancements

• It is advised to add the data to the boxplot. Viewing the data might give some weight to the statistics. Otherwise one can not distinguish between boxplots with few data and a lot of data.