Histograms

Another way of showing a distribution is to use a histogram. A histogram looks similar to a bar chart, but the bars are showing the count of occurrences of a value. For example, standardized test auditors looking for evidence of grade tampering might construct a histogram of student test scores. Typically, a distribution might look similar to this:

The test scores are shown on the X-axis and the height of each bar shows the Number of Students that made that particular score. A typical distribution should have a fairly recognizable bell curve with some students doing poorly, some doing extremely well, and most falling towards somewhere ...

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