I can think of many examples where an enmuration helps in understanding the sentence. However, I am not sure whether it is correct to put a colon before each enumeration. So which of the following sentences is incorrect?
(a) The density function can be estimated using both: (i)… and (ii) …
(b) The density function can be categorized into two categories: (i)… and (ii)
…
(c) The properties of the density function are: (i)… and (ii) …
(d) A function is called a density function whenever: (i)… and (ii) …
(e) A function is called a density function if: (i)… and (ii) …
Thanks
Best Answer
This blog post from Grammar Girl advises to only use a colon [I]f your lead-in statement is a complete sentence, use a colon at the end to introduce your list.
The Chicago Manual of Style website agrees in their FAQ.
That seems to be a good ground rule unless you are writing for anyone who has a style guide. If you are writing for a big company or a university find out if there is a style guide defining such things.