Data Science - Statistics Percentiles

25%, 50% and 75% - Percentiles

Percentiles are used in statistics to give you a number that describes the value that a given percent of the values are lower than.

Let us try to explain it by some examples, using Average_Pulse.

• The 25% percentile of Average_Pulse means that 25% of all of the training sessions have an average pulse of 100 beats per minute or lower. If we flip the statement, it means that 75% of all of the training sessions have an average pulse of 100 beats per minute or higher
• The 75% percentile of Average_Pulse means that 75% of all the training session have an average pulse of 111 or lower. If we flip the statement, it means that 25% of all of the training sessions have an average pulse of 111 beats per minute or higher

Task: Find the 10% percentile for Max_Pulse

The following example shows how to do it in Python:

• Max_Pulse = full_health_data["Max_Pulse"] - Isolate the variable Max_Pulse from the full health data set.
• np.percentile() is used to define that we want the 10% percentile from Max_Pulse.

The 10% percentile of Max_Pulse is 120. This means that 10% of all the training sessions have a Max_Pulse of 120 or lower.