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3.1 Frequency Tables

LEARNING GOAL

Be able to create and interpret frequency tables.

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Definition

A basic frequency table has two columns:

• One column lists all the categories of data.

• The other column lists the frequency of each category, which is the number of data values in the category.

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DefinitionThe relative frequency of any category is the proportion or percentage of the data values that fall in that category:

relative frequency =frequency in category total frequency

Relative Frequency

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Definition

The cumulative frequency of any category is the number of data values in that category and all preceding categories.

Cumulative Frequency

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EXAMPLE 1.1 Taste Test

Do you like hamburgers?

Rate the taste on a 5-point scale:

(Strongly Dislike) 1 2 3 4 5 (Strongly Like)

Construct a frequency and cumulative frequency table for these data.

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Relative and Cumulative Frequencies

Taste Scale

Frequency Relative Frequency

Cumulative Frequency

Relative CumulativeFrequency

       

       

       

       

       

Total      x x

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EXAMPLE 1.2 More on the Taste TestUsing the taste test data from Example 1, create a frequency table with columns for the relative and cumulative frequencies. What percentage of the respondents gave “Hamburger” the highest rating? What percentage gave “Hamburger "of the three lowest ratings?