# Statistics Lectures - 5 (Variance & Percentiles)

A series of free Statistics Lectures with examples & solutions in videos.

These lectures cover the concepts of variance, standard deviation, quartiles, percentiles, interquartile range and discuss the effects of outliers.

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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