# Numerical summaries & display

## Learning outcomes

On watching this video, students should be able to:

- Explain what is meant by descriptive statistics.
- Explain what is meant by a frequency distribution.
- Interpret histograms, identify when they are used and describe the shape of a distribution as symmetric, right skewed, left skewed, unimodal, bimodal or multimodal.
- Interpret box plots and identify when they are used.
- Describe the different summary statistics of central tendency: arithmetic mean, median mode and geometric mean, and state their appropriate use
- Describe the measures of spread: standard deviation and interquartile range, and identify situations when to use each of these.
- Define a robust statistic as a measure that is not heavily affected by skewness and extreme outliers.