They call me Ishmael
Characterization is a term that tends to hold a very specific meaning. That meaning, rather than be used to describe the dynamic fluctuations of a process or system, is typically bound to the pages of literature. In the world of writing, characterization constitutes the methods by which an author describes and develops characters as their lives unfold beneath the weight of a story. It refers to the techniques an author uses to convey to the reader how a character evolves in response to the ebb and flow of the narrative.
Although more commonly used for character development, the term characterization also applies to literary efforts that describe the world in which a story takes place. Such efforts create and define the environment in which characters live and act. They establish the context within which the events of a story occur.
Both of these elements of characterization are quintessential a reader’s understanding of a story. They impart upon the reader a sense of time and place. While we can champion the utility of characterization as a literary tool, its usefulness is best expressed through example. One such example is the opening paragraph to Herman Melville’s Moby Dick. Melville writes:
Fig 1: The fabled and feared white whale Moby Dick
“Call me Ishmael. Some years ago—never mind how long precisely—having little or no money in my purse, and nothing particular to interest me on shore, I thought I would sail about a little and see the watery part of the world. It is a way I have of driving off the spleen and regulating the circulation. Whenever I find myself growing grim about the mouth; whenever it is a damp, drizzly November in my soul; whenever I find myself involuntarily pausing before coffin warehouses, and bringing up the rear of every funeral I meet; and especially whenever my hypos get such an upper hand of me, that it requires a strong moral principle to prevent me from deliberately stepping into the street, and methodically knocking people’s hats off—then, I account it high time to get to seas as soon as I can. This is my substitute for pistol and ball. With a philosophical flourish Cato throws himself upon his sword; I quietly take to the ship. There is nothing surprising in this. If they but knew it, almost all men in their degree, some time or other, cherish very nearly the same feelings towards the ocean with me.”
While no reference to the fabled white whale called Moby Dick is made, the characterization of Ismael and his world creates a textured depiction of the readers mind. The reader is made to understand that Ishmael is a restless and dissatisfied soul defined by an adventurous and self-aware spirit. Although the times in which he lives are tough, the sea offers escape and repose.
The use of characterization in this opening paragraph is interesting because it imbues upon the reader both explicit and implicit knowledge. It establishes the novel’s narrative voice and conjures imagery in the readers mind. It reveals insights into a character’s intent and foreshadows the tides of adventure that approach. This interplay between the explicit and implicit is what expands the utility of characterization beyond the realm of literature and into the world of Statistical Process Control and process behavior charts. It is what imbues characterization with the ability to describe process behavior with a single word and, in doing so, bestows an audience with both explicit and implicit knowledge about the kinds of variation that influence process behavior.
Characterization & control charts
In the world of Statistical Process Control and process behavior charts (control charts), to characterize a process is to describe its underlying nature. It is the task of determining if future process behavior can be predicted within limits. If it can, a process is characterized as predictable. If it cannot, a process is characterized as unpredictable. Whether a process is characterized as predictable or unpredictable depends on the answer to a single question: Is all the data within the associated process limits?
Fig 2: A process is characterized as predictable or unpredictable based on the data’s relationship with the process limits
When none of the values on a process behavior chart fall outside the process limits, the process is characterized as predictable. Implicit in this characterization is the knowledge that the process is influenced by only common causes of routine variation. When one or more values on a process behavior chart fall outside the process limits the process is characterized as unpredictable. Implicit in this characterization is the knowledge that a process is influenced by both common causes of routine variation and assignable causes of exceptional variation.
The implicit knowledge that is conveyed to an audience based on the labels of predictable and unpredictable are the backbone of characterization. Like its literary counterpart, characterization imbues meaning that is both overt and implied. This puts data in a context that, without ever seeing a process behavior chart, allows an audience to understand process behavior. It bestows implicit knowledge to an audience about the types of variation that are at work and the subsequent actions that must be taken.
Fig 3: Flowchart of the logic of improvement using process behavior charts
The implicit knowledge of characterization is of particular value to management. Since, at its core, management is prediction, any tools and techniques that help management anticipate the future based on the past are invaluable. It allows management to make a plan. As Dr. W. Edwards Deming notes in his book The New Economics for Industry, Government, Education “The simplest plan—how may I go home tonight—requires prediction that my automobile will start and run, or that the bus will come, or the train.” He highlights that prediction plays a central role in everything we do. The utility of process behavior charts generally and their characterization based interpretation specifically is that they allow us to make a plan. When a process is characterized as predictable we can make a plan that anticipates the future based on the past. When a process is characterized as unpredictable, we must plan to identify, understand, and eliminate the influence of assignable causes.