Assessing Class Interval Construction

00:00 4 marks

In a histogram constructed from a dataset with variable class interval widths, using raw frequencies on the vertical axis can lead to a misleading visual representation.

Explain why it is essential to use frequency density instead of absolute frequency when constructing such histograms. In your explanation, define frequency density and describe its crucial role in providing an accurate visual depiction of the data.

Hint Hint

Hint

Remember that frequency density is calculated by dividing the frequency of a class by its width. This normalization accounts for the varying interval lengths.

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Complete Answer

Frequency density is calculated by dividing the frequency of a class interval by its width. This adjustment is crucial because it ensures that the area of each bar in the histogram is proportional to the frequency of the class, regardless of the interval width. Using frequency density prevents wider intervals from appearing disproportionately frequent, thus providing a true representation of the data distribution.

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