relative frequency

(noun)

the fraction or proportion of times a value occurs

Related Terms

Examples of relative frequency in the following topics:

  • Relative Frequency Distributions

    • The third column should be labeled Relative Frequency.
    • The only difference between a relative frequency distribution graph and a frequency distribution graph is that the vertical axis uses proportional or relative frequency rather than simple frequency.
    • Cumulative relative frequency (also called an ogive) is the accumulation of the previous relative frequencies.
    • To find the cumulative relative frequencies, add all the previous relative frequencies to the relative frequency for the current row.
    • This graph shows a relative frequency histogram.

  • Sampling Distributions and Statistic of a Sampling Distribution

    • You can think of a sampling distribution as a relative frequency distribution with a great many samples.
    • (See Sampling and Data for a review of relative frequency).
    • The results are in the relative frequency table shown below.
    • If you let the number of samples get very large (say, 300 million or more), the relative frequency table becomes a relative frequency distribution.

  • Frequency

    • The sum of the relative frequency column is 20/20 , or 1.
    • Cumulative relative frequency is the accumulation of the previous relative frequencies.
    • To find the cumulative relative frequencies, add all the previous relative frequencies to the relative frequency for the current row.
    • To find the relative frequency, divide the frequency by the total number of data values.
    • To find the cumulative relative frequency, add all of the previous relative frequencies to the relative frequency for the current row.

  • Do It Yourself: Plotting Qualitative Frequency Distributions

    • Sometimes a relative frequency distribution is desired.
    • If this is the case, simply add a third column in the table called Relative Frequency.
    • Bar graphs for relative frequency distributions are very similar to bar graphs for regular frequency distributions, except this time, the y-axis will be labeled with the relative frequency rather than just simply the frequency.
    • Since a circle has 360 degrees, this is found out by multiplying the relative frequencies by 360.
    • This graph shows the relative frequency distribution of a bag of Skittles.

  • Summary

  • Creating a Sampling Distribution

    • The relative frequencies are equal to the frequencies divided by nine because there are nine possible outcomes.
    • The figure below shows a relative frequency distribution of the means.
    • This distribution is also a probability distribution since the $y$-axis is the probability of obtaining a given mean from a sample of two balls in addition to being the relative frequency.
    • After thousands of samples are taken and the mean is computed for each, a relative frequency distribution is drawn.
    • The more samples, the closer the relative frequency distribution will come to the sampling distribution shown in the above figure.

  • Practice 1: Center of the Data

    • Exercise 2.11.2: What does the relative frequency column sum to?
    • Exercise 2.11.3: What is the difference between relative frequency and frequency for each data value?
    • Exercise 2.11.4: What is the difference between cumulative relative frequency and relative frequency for each data value?

  • Optional Collaborative Classrom Exercise

    • In your class, have someone conduct a survey of the number of siblings (brothers and sisters) each student has.Create a frequency table.Add to it a relative frequency column and a cumulative relative frequency column.Answer the following questions:

  • Recognizing and Using a Histogram

    • The vertical axis is labeled either frequency or relative frequency.
    • The relative frequency (or empirical probability) of an event refers to the absolute frequency normalized by the total number of events:
    • Put more simply, the relative frequency is equal to the frequency for an observed value of the data divided by the total number of data values in the sample.
    • The height of a rectangle in a histogram is equal to the frequency density of the interval, i.e., the frequency divided by the width of the interval.
    • A histogram may also be normalized displaying relative frequencies.

  • Guidelines for Plotting Frequency Distributions

    • In statistics, the frequency (or absolute frequency) of an event is the number of times the event occurred in an experiment or study.
    • These frequencies are often graphically represented in histograms.
    • The relative frequency (or empirical probability) of an event refers to the absolute frequency normalized by the total number of events.
    • The height of a rectangle is also equal to the frequency density of the interval, i.e., the frequency divided by the width of the interval.
    • A histogram may also be normalized displaying relative frequencies.