IN THIS CHAPTER
Working with things great and small
Understanding symmetry, peaks, and plateaus
Experiencing special moments
The measures of central tendency and variability that I discuss in earlier chapters aren’t the only ways of summarizing a set of scores. These measures are a subset of descriptive statistics. Some descriptive statistics — like maximum, minimum, and range — are easy to understand. Some — like skewness and kurtosis — are not.
This chapter covers descriptive statistics and shows you how to calculate them in R.
Perhaps the fundamental descriptive statistic is the number of scores in a set of data. In earlier chapters, I work with length(), the R function that calculates this number. As in earlier chapters, I work with the Cars93 data frame, which is in the MASS package. (If it isn’t selected, click the check box next to MASS on the Packages tab.)
Cars93 holds data on 27 variables for 93 ...