What Does Histogram Mean?

A histogram is a type of graph that is widely used in mathematics, especially in statistics. The histogram represents the frequency of occurrence of specific phenomena which lie within a specific range of values, which are arranged in consecutive and fixed intervals. The frequency of the data occurrence is represented by a bar, hence it looks very much like a bar graph.


Techopedia Explains Histogram

A histogram is a graphical representation of the distribution of data, which is an estimate of the probability distribution of a continuous variable, usually in bar graph form, and was first introduced by Karl Pearson in 1891.

The first step in creating a histogram is to divide the entire value range into a series of intervals called “bins” and then to “drop” the individual values into the bins that they belong to. The width of the bin is determined by the range and may or may not be equal to the other bins. If the bins are of equal width, then the height or vertical axis of the bar determines the frequency of the occurrence for that set, but if the bins are not of equal width, then the area of the bar or rectangle represents the frequency of occurrence while the vertical axis represents the density. In both cases, all the bars in the histogram touch to indicate that the variable or data is continuous.

This can be used to visualize data or phenomena with both a contiguous factor and an occurrence factor. For example, a histogram can be used to visualize the commute time of people going to work with the horizontal axis representing time, so the bins are divided according to time, while the vertical axis represents the number of people that fall under that specific travel time.


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Margaret Rouse is an award-winning technical writer and teacher known for her ability to explain complex technical subjects to a non-technical, business audience. Over the past twenty years her explanations have appeared on TechTarget websites and she's been cited as an authority in articles by the New York Times, Time Magazine, USA Today, ZDNet, PC Magazine and Discovery Magazine.Margaret's idea of a fun day is helping IT and business professionals learn to speak each other’s highly specialized languages. If you have a suggestion for a new definition or how to improve a technical explanation, please email Margaret or contact her…