Intervals & Tests
The 50th percentile.
The median of a sample of data is found by rank ordering the data from smallest to largest value, then selecting the data value that is in the middle of the sample. It will have an equal number of data values greater than it and less than it. When there are an even number of data values, use the average of the two central values.
The median of a distribution is determined as the 50th percentile point once the distribution has been defined.
For normal distributions, the median value occurs at the average of the distribution. This is also where the mode, or high point (most frequently occurring value), of the distribution occurs.
For distributions skewed left, both the median and mode occur to the left of (are smaller than) the average of the distribution.
For distributions skewed right, both the median and mode occur to the right of (are larger than) the average of the distribution.
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