Basic Statistics
Median, mean, mode, and range are basic statistical measurements.
Mean
Mean measures the average of a dataset.
Calculation:
1. add all datapoints
2. divide by the total number of datapoints
Example:
5 + 2 + 3 + 11 + 8 + 1 = 30
Number of datapoints = 6
30 ÷ 6 = 5 (mean or average)
Median
Median measures the middle point of a dataset.
Calculation:
1. put all datapoints in order
2. find the middle datapoint
Example:
5, 2, 7, 3, 7, 4, 9
2, 3, 4, 5, 7, 7, 9 (ordered)
5 (median)
Note: if the number of datapoints is even (6 for instance), add the 2 middles (3rd & 4th), and divide by 2.
Mode
Mode measures the most common datapoint within a dataset.
Calculation:
1. put all datapoints in order
2. find the most common
Example:
5, 2, 7, 3, 7, 4, 9
2, 3, 4, 5, 7, 7, 9 (ordered)
7 (mode)
Note: mode can have more than 1 outcome, if for example 2 or more datapoints have equal number of occurrences.
Range
Range measures the difference between the smallest and biggest datapoint in a dataset.
Calculation:
1. find the highest and lowest datapoint
2. subtract the lowest from the highest datapoint
Example:
5, 2, 7, 3, 7, 4, 9
9 (highest) & 2 (lowest)
9 – 2 = 7 (range)
