attendance vs frequency

attendance and frequency both are nouns.

Word	Noun	Adjective	Verb	Adverb
attendance	Yes	No	No	No
frequency	Yes	No	No	No

As nouns, frequency is a hypernym of attendance; that is, frequency is a word with a broader meaning than attendance:

Other hypernyms of attendance include frequence, oftenness.

attendance (noun)	frequency (noun)
the act of being present (at a meeting or event etc.)	the number of observations in a given statistical category
the number of people that are present	the ratio of the number of observations in a statistical category to the total number of observations
the frequency with which a person is present	the number of occurrences within a given time period