Histogram

Histogram

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Tufte-approved histogram. This histogram has minimal non-data ink and a widely distributed data set.

Global MBA rankings. This is a block histogram where each block represents a school in a numeric bin. Its interactivity provides a datatip that allows more information about the data points than a static histogram would provide.


Description

Visually represents frequencies in a dataset via vertical bars. A histogram shows what proportion of the data set falls within certain categories. It differs from bar charts in that the area of the bar, not the height, denotes its quantitative value. Use this to show a comparison of frequencies between categories within a data set. Good for giving an overall sense of data distribution at first glance.



Considerations

  • Exact values may be hard to determine or hard to fit into the chart and thus are approximate. An interactive histogram such as the ones at ManyEyes can show exact values using a datatip.
  • At first glance, it looks identical to a regular bar chart, and the varying width and height values may confuse non-visualization-literate users.
  • For histograms that rely on area rather than just height, discretion should be used. The user's visual estimate of an area is not as fast or accurate as visual estimation of other properties, such as color or height.

Related techniques

The block histogram: Like a classic histogram, it shows a distribution of numeric values over a data set in the form of vertical bars. Unlike the classic histogram, the bars are separated into equal-sized blocks piled on top of one another. These blocks are arranged to show quantitative value and give a sense of how many values are in each range.

Links



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