Structure of stories: 3 act structure and 4 act structure

"Stories have shapes which can be drawn on graph paper, and that the shape of a given society's stories is at least as interesting as the shape of its pots or spearheads."

Our ability to communicate relies in part upon a shared emotional experience, with stories often following distinct emotional trajectories and forming patterns that are meaningful to us." These emotional trajectories are equivalent to Vonnegut's "story shapes."

As we know most of the stories in the west follow a 3 act structures with a clear central conflict:

The traditional three-act structure includes the following parts: 

Act I - Setup: Exposition, Inciting Incident, Plot Point One. 

Act II - Confrontation: Rising Action, Midpoint, Plot Point Two.

 Act III - Resolution: Pre Climax, Climax, Denouement

However in the East 4 act structure minus conflict is most often used:

Ki : Introduction
Shō : Development
Ten : Twist (complication)
Ketsu : Conclusion (reconciliation) 

On studying 10000 books some researchers found that there are 6 types of story shapes: (https://epjdatascience.springeropen.com/articles/10.1140/epjds/s13688-016-0093-1) :

• Rags to riches (rise): SV 1

  • A steady, ongoing rise in emotional valence, as in a rags-to-riches story, such as Alice's Adventures Undergroundby Lewis Carroll.

• Tragedy or Riches to rags (fall): SV 1

  • A steady ongoing fall in emotional valence, as in a tragedy such as Romeo and Juliet.

•  Man in a hole (fall-rise): SV 2

  • A fall, then a rise, such as the man-in-a-hole story, discussed by Vonnegut.

•  Icarus (rise-fall): SV 2

  • A rise, then a fall, such as the Greek myth of Icarus. 

• Cinderella (rise-fall-rise): SV 3

  • Rise-fall-rise, such as Cinderella.

•  Oedipus (fall-rise-fall): SV 3

• Fall-rise-fall, such as Oedipus.

They found that "Icarus," "Oedipus," and "Man-in-a-hole" were the three most successful emotional arcs.