gf_dhistogram()

The gf_dhistogram() function is very similar to the gf_histogram() function, however, the difference is that gf_dhistogram() will create a density histogram for a quantitative variable. This means it will show the percentage of cases for each value of the variable, whereas, gf_histogram() will show the count of the cases for each value of the variable. In other words, a density histogram will give you the relative frequency of values, while, a regular histogram will give you the raw frequency.

A density histogram is also known as a relative frequency histogram.

Example 1:

# Create a density histogram

# Notice the y-axis is labeled as "density" and the units are percentages

gf_dhistogram( ~ Thumb , data = Fingers )

Example of output from running the code above:

Example 2:

# Create a frequency histogram

# Notice the y-axis is labeled as "count" and the units are raw values

gf_histogram( ~ Thumb , data = Fingers )

Example of output from running the code above:

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