names-a vector of names for the groups.group-a vector of the same length as out whose elements indicate to which group the outlier belongs and.conf-upper/lower extremes of the notch, out-value of the outliers.n-the number of observation the boxplot is drawn with (notice that NAвЂs are not taken into account).> b bДЄs we can see above, a list is returned which has stats-having the position of the upper/lower extremes of the whiskers and box along with the median, The boxplot() function returns a list with 6 components shown as follows. Main = 'Mean ozone in parts per billion at Roosevelt Island', Some of the frequently used ones are, main-to give the title, xlab and ylab-to provide labels for the axes, col to define color etc.ДЄdditionally, with the argument horizontal = TRUE we can plot it horizontally and with notch = TRUE we can add a notch to the box. You can read about them in the help section ?boxplot. We can pass in additional parameters to control the way our plot looks. We can also notice two outliers at the higher extreme.

We can see that data above the median is more dispersed. Let us make a boxplot for the ozone readings. Let us use the built-in dataset airquality which has вЂњDaily air quality measurements in New York, May to September 1973.вЂќ-R documentation. You can also pass in a list (or data frame) with numeric vectors as its components. The boxplot() function takes in any number of numeric vectors, drawing a boxplot for each vector. In R, boxplot (and whisker plot) is created using the boxplot() function.

Box and whisker plot in r