Mode
The value that appears most often in a data set.
Formula
Variables
Example
2,3,3,5: mode=3
How it works
The mode is the data value that occurs more times than any other value in a set. It is useful because repeated values reveal the most common outcome, so the mode summarizes the center by frequency rather than by arithmetic size. Unlike the mean, it is not affected by very large or very small values, which makes it especially helpful for categorical data or data with repeats.
When to use it
Use the mode when you want to find the most common choice, result, or score in a list. It is often used in surveys, sales data, test scores, and any situation where identifying the most frequent category or value matters more than averaging.
Worked example, step by step
Data: 4, 7, 7, 8, 9, 7, 10 Count how often each value appears: 4 appears 1 time 7 appears 3 times 8 appears 1 time 9 appears 1 time 10 appears 1 time The value with the highest frequency is 7. Mode = 7
Common mistakes to avoid
- Choosing the middle value instead of the most frequent value
- Forgetting that a data set can have more than one mode if two values tie
- Thinking the mode must be different from every other data summary measure
Did You Know?
The mode is the only average that works for non-numerical data like favourite colours or blood types.
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