Constructing
a Cumulative Frequency Table
©2008, J. T. Stocks, Ph.D.
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Cumulative Frequencies
We may calculate cumulative frequencies
only for variables measured at the ordinal,
interval or ratio levels.
For a specific value within a distribution of
values, its cumulative frequency refers to the
number of values in the distribution that are
less than or equal to the specified value.
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Cumulative Frequency Table
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Calculating Cumulative Frequencies
The cumulative frequency (cf) for a specific value
within a distribution equals the frequency for the
value plus the cumulative frequency for value
immediately below, or
cf = f + cfBelow
where
cf refers the number of values less than or equal to
a specified value in a distribution
f refers to the number of values equal to a
specified value in a distribution
cfBelow refers to the number of values less than a
specified value in a distribution
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Cumulative Frequency of Scores
Less Than or Equal to Y=1
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2
Cumulative Frequency of Scores
Less Than or Equal to Y=2
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Cumulative Frequency of Scores
Less Than or Equal to Y=3
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Cumulative Frequency of Scores
Less Than or Equal to Y=4
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3
Cumulative Frequency of Scores
Less Than or Equal to Y=5
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Cumulative Frequency of Scores
Less Than or Equal to Y=6
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Cumulative Frequency of Scores
Less Than or Equal to Y=7
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Cumulative Frequency of Scores
Less Than or Equal to Y=8
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Cumulative Frequency Table
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