Graziano & Raulin
Research Methods (9th edition)
Computing the Mode
The mode is the most frequent score in the distribution. To compute the mode, prepare a frequency distribution for the variable as shown in Chapter 5. Then select the most frequently occurring score in the distribution. If two scores or categories share the title of most frequently occurring score, the distribution is said to be bimodal, and both modes should be reported. If three scores or categories share the title of most frequently occurring score, the distribution is said to be trimodal, and all three modes should be reported.
The mode can be used with any type of data, including nominal data.