formality: Formality Score
In trinker/formality: Calculate Text Formality

Description Usage Arguments Details Warning References Examples

Formality score by grouping variable(s).

1 2	formality(text.var, grouping.var = NULL, order.by.formality = TRUE, group.names, ...)

`text.var`	The text string variable or another `formality` object. The latter recycles the part of speech tagging and is much faster.
`grouping.var`	The grouping variable(s). Default `NULL` generates one word list for all text. Also takes a single grouping variable or a list of 1 or more grouping variables. If `TRUE` an `id` variable is used with a `seq_along` the `text.var`.
`order.by.formality`	logical. If `TRUE` orders the results descending by formality score.
`group.names`	A vector of names that corresponds to group. Generally for internal use.
`...`	ignored.

Heylighen & Dewaele(2002)'s formality F-measure is defined formally as:

F = 50(n_f-n_c/N + 1)

Where:

f = {noun,adjective, preposition, article}

c = {pronoun, verb, adverb, interjection}

N = ∑(f + c)

This yields an F-measure between 0 and 100%, with completely contextualizes language on the zero end and completely formal language on the 100 end.

Heylighen & Dewaele (2002) state, "At present, a sample would probably need to contain a few hundred words for the measure to be minimally reliable. For single sentences, the F-value should only be computed for purposes of illustration" (p. 24).

Heylighen, F. (1999). Advantages and limitations of formal expression. doi:10.1023/A:1009686703349

Heylighen, F. & Dewaele, J.-M. (1999). Formality of language: Definition, measurement and behavioral determinants. Center "Leo Apostel", Free University of Brussels. Retrieved from http://pespmc1.vub.ac.be/Papers/Formality.pdf

Heylighen, F. & Dewaele, J.-M. (2002). Variation in the contextuality of language: An empirical measure. Foundations of Science, 7(3), 293-340. doi:10.1023/A:1019661126744

data(presidential_debates_2012)
(form1 <- with(presidential_debates_2012, formality(dialogue, person)))
with(presidential_debates_2012, formality(form1, list(person, time))) #recycle form 1 for speed

plot(form1)
plot(with(presidential_debates_2012, formality(form1, list(person, time))))