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teddwhy t1_iqmwho8 wrote

On graphs like this, why is the median often used over the mean? What would the difference be in this context?

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Brayzure t1_iqn4w0q wrote

To my understanding, it's because in data sets like these, median is usually closer to what we want. If you had a room with 9 infants and 1 hundred year old person, it's not helpful to say the average age of a person in that room is 10. It's usually more helpful to say the median age is 0, since most people in that room are newborns. Mean is affected by outliers, median is not.

In reality the difference between mean and median for an entire country is minor, but the point is that the median is closer to what we want. Median also gives us a useful data point, the age where half of all people are older than that age, and half are younger. Mean age is less useful.

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BoomZhakaLaka t1_iqpzb8w wrote

Median gives you the 50th percentile, what we intuitively would consider "an average person". For instance, the average adult's net wealth in the US is around $600k, but that's actually the 80th percentile. A median adult's wealth in the US (what we would intuitively think of as an "average person"), the 50th percentile, is closer to $100k (little variation depending on whose survey you use). The difference between mean and median shows just how unequal the distribution of wealth is.

Not intentionally choosing controversy here - I've limited my statements to just plain facts, not opinions.

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