Basic Summary Statistics

Abstract

This chapter includes the basic measures of summary statistics , namely measures of central tendency , measures of dispersion , measures of skewness , and measures of kurtosis . These summary measures of descriptive statistics characterize the underlying features of data . The measures of central tendency include arithmetic mean , median , and mode with examples, advantages and disadvantages of the measures are highlighted. The measures of dispersion are discussed along with their properties. The measures of dispersion include range , variance , standard deviation , coefficient of variation , and interquartile range . In statistics and biostatistics, the first measure, central tendency or location, provides the central value around which all other values in the data set are located. In other words, the measure of central tendency provides the most important representative value of the data set. The dispersion quantifies or measures the variability in the data where variability between values of the data or difference between each value and the measure of central tendency may reflect how scattered the data are from a central value or what extent in variation among values of the data is there. The third measure is used to know whether there is symmetry from the central value or there exists asymmetry from the central value. The fourth measure indicates whether the data are more concentrated with high peak, low or normal peaks, or frequencies indicating the extent of concentration of values.