My latest education video is a short one showing how to determine the Median value in a data set. This plugs a small gap in my How To... Statistics by Hand playlist. The Median value in a data set is the middle value when the data are ranked from highest to lowest (or vice versa). This is easy to determine when there are an uneven/odd numbers of values, but not as easy when there are an even number of values. Here's how it works:
The Median is a useful measure in that it is not affected by skewed data. If you think about the average salary in a large company versus the median value - you may get a very different picture. Felim O'Rourke writing in TheJournal.ie "64% of workers in Ireland earn less than the 'average' salary", tells us that "the average earnings in 2017 were €37,646". He compares the mean value and the Median value concluding that the Median gives a better insight. The average value includes high earners whose salaries in the hundreds of thousands skew this average value upwards. For example, if there are 10 people working in a company and 9 of them earn €30,000 each while the 10th earns €60,000 - the average salary will be €33,000, but the Median value will be €30,000. Statisticians and data analysts should always consider the Median when describing data, as it can give a different and maybe more important insight into the data.