Variance, standard deviation and interquartile range are measures of dispersion, giving a idea of how the data is spread out.

This is the fifth page of the series of free video lessons, "Statistics Lectures".

### Statistics - Lecture 11

Measures of Dispersion: Variance and Standard Deviation of a Population

### Statistics - Lecture 12

Measures of Dispersion: Variance and Standard Deviation of a Sample

### Statistics - Lecture 13

Percentiles and Quartiles

A percentile is a value below which a certain percentage of observations lie.

### Statistics - Lecture 14

The Five Number Summary, Interquartile Range (IQR), and Boxplots

The five number summary is a method of summarizing a distribution of data.

1. Minimum

2. First Quartile (Q1)

3. Median

4. Third Quartile (Q3)

5. Maximum

### Statistics - Lecture 15

The Effects of Outliers

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