The six story arcs are these:

1. An ongoing rise of positive feeling, as in a rags-to-riches story.

2. An ongoing fall of positive feeling, as in a tragedy like Romeo and Juliet.

3. A fall then a rise. Something bad happens, but it all works out in the end, as in the man-in-hole example Kurt Vonnegut will tell us about on the next page.

4. A rise then a fall, like the Greek myth of Icarus.

5. Rise-fall-rise, such as Cinderella.

6. Fall-rise-fall, such as Oedipus.

The MIT team looked at the correlation between the emotional arcs in a story and its number of online downloads.

It turns out the most popular are stories that follow the Icarus arc (#4,) and the Oedipus arc (#6,) and stories that use multiple arcs in sequence. In particular, stories involving two sequential man-in-hole arcs (#3) and a Cinderella arc (5) followed by a tragedy (#2.)

– From the MIT Technology Review
Data Mining Reveals the Six Basic Emotional Arcs of Storytelling
by Emerging Technology from the arXiv July 6, 2016