# Descriptive Statistics

• Allen M. Khakshooy
• Francesco Chiappelli
Chapter

## Abstract

We finally approach the third and final leg of our “three-legged” stool, particularly data analysis. In the remaining chapters of the first half of the book, we will look at inferential and descriptive statistics, but for now, we direct our attention to the latter. Unlike inferential statistics, descriptive statistics does not attempt to make inferences from a sample to the whole population. As its name suggests, descriptive statistics describes, summarizes, or presents the sample and the observations that have been made based on the data collected in an organized manner.

## Keywords

Descriptive statistics Tabulation Frequency table Frequency percent (f%) Cumulative frequency (cf) Cumulative frequency percent (cf%) Midpoint Histogram Bar chart Frequency polygon Measures of central tendency Mean Median Mode Measures of variability Range Outliers Interquartile range (IQR) Standard deviation Variance Parameters Statistics Normal distribution Positively skewed (or right-skew) distribution Negatively skewed (or left-skew) distribution Bimodal distribution Polymodal distributions Probability Multiplication rule Independence Addition rule Mutually exclusivity Dependent Conditional rule Bayes theorem Z-score

## Supplementary material

Video 2

Frequency tables. Reprint courtesy of International Business Machines Corporation, © International Business Machines Corporation (MOV 79842 kb)

Video 3

## Bibliography

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© Springer-Verlag GmbH Germany, part of Springer Nature 2018

## Authors and Affiliations

• Allen M. Khakshooy
• 1
• Francesco Chiappelli
• 2
1. 1.Rappaport Faculty of MedicineTechnion-Israel Institute of TechnologyHaifaIsrael
2. 2.UCLA School of DentistryLos AngelesUSA