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Histogram charts
Last updated: Oct 09, 2024
Histogram charts
A histogram is similar in appearance to a bar chart, but instead of comparing categories or looking for trends over time, each bar represents how data is distributed in a single category. Each bar represents a continuous range of data or the number of frequencies for a specific data point.

Histograms are useful for showing the distribution of a single scale variable. Data are binned and summarized by using a count or percentage statistic. A variation of a histogram is a frequency polygon, which is like a typical histogram except that the area graphic element is used instead of the bar graphic element.

Another variation of the histogram is the population pyramid. Its name is derived from its most common use: summarizing population data. When used with population data, it is split by gender to provide two back-to-back, horizontal histograms of age data. In countries with a young population, the shape of the resulting graph resembles a pyramid.

Creating a histogram chart

  1. In the Chart Type section, click the Histogram icon.

    The canvas updates to display a histogram chart template.

  2. Select a scale variable as the X-axis variable.
    Note: The statistic for a histogram is Histogram or Histogram Percent. These statistics bin the data and calculate a count for each bin.
  3. Click the Save visualization in the project control to save the visualization to the project. You can select to also Create a new asset from the visualization, provide a visualization asset name, description, and chart name.
  4. Click Apply to save the visualization to the project. The new visualization asset is now available under the Assets tab.

Options

X-axis
Lists variables that are available for the chart's X-axis.
Split by
Select a categorical variable that creates a table of charts, with a cell for each category in the Split by variable. Like grouping, split by variables essentially add more dimensions to your chart by displaying information for each variable category.
Bin method
Specify a bin method that is used to create the chart bars. Available option include Auto bin, By bin width, and By bin num.
Show kde curve
When enabled, the kernel density estimate curve is shown on the chart.
Show distribution curve
When enabled, the distribution fitting curve is shown on the chart.
Distribution
The drop-down list provides to the following distribution options.
Auto fit distribution
Automatically fits the distribution (the default setting).
Beta
Returns the value from a Beta distribution with specified shape parameters.
Exponential
Returns the value from an exponential distribution.
Gamma
Returns the value from the Gamma distribution, with the specified shape and scale parameters.
Log-normal
Returns the value from a log-normal distribution with specified parameters.
Normal
Returns the value from a normal distribution with specified mean and standard deviation.
Triangular
Returns the value from a triangular distribution with specified parameters.
Uniform
Returns the value from the uniform distribution between the minimum and maximum.
Weibull
Returns the value from a Weibull distribution with specified parameters.
Bin width
The slider controls the size of the interval that is used to split the data into groups.
Primary title
The chart title.
Subtitle
The chart subtitle, which is placed directly beneath the chart title.
Footnote
The chart footnote, which is placed beneath the chart.
XAxis label
The x-axis label, which is placed beneath the x-axis.
YAxis label
The y-axis label, which is placed above the y-axis.
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