Question

What does it mean for data to be an outlier?
how does an outlier appear on the graph?

Answer 1

Outlier. ... A convenient definition of an outlier is a point which falls more than 1.5 times the interquartile range above the third quartile or below the first quartile. Outliers can also occur when comparing relationships between two sets of data.

Answer 2

On a graph, outliers are points that don't necessarily follow the trend in the data and outliers happen all the time in real life. It's basically an observation that's different from the other values on a graph. Typically you can see it with your own eyes and see how different the value is from the rest of the points.