sample range sample variance the sample mean and median give information about the location of the datawhile the distance between sample quantiles (say the and quantilesgives some indication of the dispersion (spreadof the data other measures for dispersion are the sample rangemaxi xi mini xi the sample variance (xi ) = sample standard deviation and the sample standard deviation ( for the nutri datathe range (in cmisnutri ['height 'max (nutri ['height 'min ( the variance (in cm isround nutri ['height 'var ( round to two decimal places and the standard deviation can be found viaround nutri ['height 'std ( we already encountered the describe method in the previous section for summarizing qualitative featuresvia the most frequent count and the number of unique elements when applied to quantitative featureit returns instead the minimummaximummeanand the three quartiles for examplethe 'heightfeature in the nutri data has the following summary statistics nutri ['height 'describe (count mean std min \ \ \ max nameheight dtype float visualizing data in this section we describe various methods for visualizing data the main point we would like to make is that the way in which variables are visualized should always be adapted to the variable typesfor examplequalitative data should be plotted differently from quantitative data