Long and Short Sentences in Statistics and in Spirit
No statistic about sentence length will ever be as the imperative to "write music," to borrow Gary Provost's phrase. Still, quantitative tools can help us see the tendencies of our own writing. They can imply the kind of music we're writing and, perhaps, places where we might want to vary the tune.
The introduction to this section already showed you CATPAW's tool for visualizing sentence length graphically. Now we can add two more tools: measures of average length and standard deviation. Simply put, these tools tell you how long your sentences are and how much their length varies.
I do not offer these tools to push you to write shorter or longer sentences. Like CATPAW's other tools, these will help you see your own writing in relation to that of other authors, then make informed choices about writing strategy.
Remember, too, that the same writer will use different strategies for different audiences and situations. Scholarly articles, newspaper stories, and children's books require different rhetorical strategies. In general, I encourage students mainly to strive for creating thoughtful variety in sentence length and structure.
Let's look at some sophisticated writers using that kind of thoughtful variety of sentences in literature.