BAC-GROUND Groundwater Consulting Support



A Theory on the Relationship Between Personalities and Groundwater Modeling


A couple of years ago I saw a book about personalities, I read it and got hooked on the topic. Since then I have been reading books, web pages, and analyzing everyone I see. What I found out was enlightening! One of the best sources is David Keirsey's book "Please Understand Me II" (1998). If you want to analyze your own personality you can take the test. I wi ll use Keirsey's nomenclature in this write up. In fact, the way I responded after finding an interesting topic, such as this one, was very typical of someone of my personality.

But what about groundwater modeling? As you can see in my resume, I have been working with groundwater models since the early 1980s. Recently there has been a lot of discussion in one of the internet groundwater mail ing list groups ( about models, modelers, and standards or guidelines. As I read through the comments I realized that they represent var ious points of view, which in turn relate to the authors' personalities.


One of the most surprising facts I found about personality analysis is that there are only 16 personalities. In fact, Keirsey talks about four (4) temperaments. Each temperament consists of four personalities. A temperament is just an inclinat ion to do things in a particular way. For practical purposes, identification of someone's temperament is sufficient to learn much about his probable behavior and to explain his thinking. In fact, it is even simpler than that because about 85% of a random population belong to only two of these temperaments.

Most studies on personalities use four pairs of variables which are combined to describe the 16 personality types. The temperaments are described by two of those variables. I will briefly describe each of these variables. I highly recommend reading Keirsey's book for a more thorough description.

Sensation (S) vs iNtuition (N)

The Sensation versus iNtuition personality measure is probably the most important of all. A Sensing person is one who primarily uses his senses, i.e., sight, touch, taste, hearing, and smell, to learn and deal with the world around him. This ten dency makes these people very concrete and practical. Most people (85%) are sensors. People who use iNtuition are the dreamers. They do not like to deal with the concrete world, they would rather think about the world that can be created in their minds. T hey imagine, theorize, daydream, and conceptualize. They are the idea generators. Although anyone can move back and forth between these two states, people have a strong preference to staying in either the S or N mode.

Judging (J) vs Perception (P)

For the Sensors, the next most important measure is Judging versus Perception. This measure has to do with how they prefer to work. Judgers are structured, are organized, like to do things in a linear fashion, like things done on a schedule, and like to develop rules to be followed by all. These tendencies make them very dependable, detail oriented, and likely to carry on each task to completion. People who prefer Perception are very flexible, adaptable, and always looking for alternative (creative) w ays of doing things. These tendencies enable them to improvise when the unexpected occurs.

Thinking (T) vs Feeling (F)

For the iNtuitives, the next most important measure is Thinking versus Feeling. This measure has to do with how they make decisions. Thinkers use their "heads" to make decisions, while Feelers use their "hearts". Feelers like to show their emotions wh ile Thinkers like to be in control of themselves and do not like to show their emotions. Feelers are very friendly and people oriented. Thinkers tend to be analytical and task oriented.

Extroversion (E) vs Introversion (I)

This is the least significant personality variable, but tends to be quite visible and is generally easy to identify. It is possible for someone to be borderline Extrovert/Introvert. This personality variable refers to how someone is energized, external ly as the Extroverts, or from within for the Introverts. Generally, Extroverts prefer to communicate verbally and tend to be impatient. Introverts prefer to write and are more patient.


Using Keirsey's labels the four temperaments will be described in order of most prevalent to least.

Guardians (SJ)

If one did not know anything about a person, a good bet would be to guess that (s)he is of a Guardian temperament. There are about 45% Guardians in the general population. Guardians are conservative, business minded, cautious, detail oriented, reliable , and hard working.

Artisans (SP)

About 40% of the general population are Artisans. Artisans are fun loving, risk taking, improvisors, competitive, artistic, good tool users, and great negotiators.

Idealists (NF)

Only about 9% of the general population are Idealists. They are very friendly, people oriented, diplomatic, helpful, motivating, and inspiring.

Rationals (NT)

Only about 6% of the general population are Rationals. This rare group is attracted to logic, science, engineering, and the pursuit of knowledge.

Groundwater Modeling

OK, so what does any of this have to do with groundwater modeling?

Although no temperament is better than any other, depending on what one is trying to accomplish, some temperaments are better at doing certain tasks than others. Generally, groundwater modeling requires development of a conceptual model, developing a s trategy for getting to the goal of the project, patience to analyze and gather the necessary data, ability to use the appropriate tools (i.e., selecting the appropriate computer software), organizational skills to manage large data sets (e.g., data arrays for numerical models), artistic sense for data presentation, among other skills.

My opinion is that Feelers (F) would probably not be attracted to quantitative groundwater modeling since there would be very little interaction with other people or emotional involvement during the modeling process.

Guardians (SJ) as Groundwater Modelers

There are four types of Guardians (ISTJ, ESTJ, ISFJ, and ESFJ). As mentioned above the Feeler Guardians (*SFJ) would probably not be inclined to do any quantitative groundwater modeling. The other two types (ISTJ and ESTJ) could be attracted to modelin g. In fact, most groundwater modelers (I venture to guess) are of the ISTJ personality type. Part of the reason is because there are about 9% of ISTJs, or Inspectors (using Keirsey's label), in the general population. If they study this field and work at it, they can become very good groundwater modelers.

Artisans (SP) as Groundwater Modelers

There are four types of Artisans (ISTP, ESTP, ISFP, and ESFP). Again, the Feeler Artisans (*SFP) would probably not be inclined to do any quantitative groundwater modeling. In fact, the Feeler Artisans probably make the worst groundwater modelers if yo u can even get them interested in working in such a project. The other two types (ISTP and ESTP) might be interested but for other reasons. Since these types are good at using tools, i.e., computers, they could have a lot of fun playing with the mo dern software with the graphical interfaces. They would not show any interest in the old fashioned software. The output is bound to be artistic or even flashy (e.g., animation of rainbow colored plumes shooting out of the sources in rapid successio n). The problem is that it may not have any relevance to the task at hand, which, of course, would not matter that much to them, because they would just improvise an answer to their superiors and/or clients.

Idealists (NF) as Groundwater Modelers

The Idealists would not be inclined to quantify a site by groundwater modeling, although they are quite capable if pushed into it. Despite their modeling aversion, they would be able to provide an accurate conceptual model of the site and could identif y all of the important components needed for modeling. Since iNtuition (N) is a major part of these personalities, they would have a more global view of all factors that may affect the shape of the plume.

Rationals (NT) as Groundwater Modelers

Rationals make the best groundwater modelers. They are very attracted to this field and will naturally tend to learn as much as possible about it. INtuition (N) allows them to develop a good conceptual model and their Thinking (T) personality measure a llows them to analyze all aspects of the site. The Rational Architect (INTP) are the best modelers of all (see Keirsey, " the model is the thing ," p. 206). This type is ob sessed with analysis. Unfortunately, this type of modeler (INTP) is quite rare in the general population (probably less than 1%).


Ideally, a groundwater model should be conceptualized and analyzed by a Rational (NT), preferably an Architect (INTP). The details of mechanically running such a model and organizing the datasets should be left to a Guardian Inspector (ISTJ). Such a te am would be hard to beat by any other team of experts.

Recently there have been many discussions on (an internet groundwater group) about ASTM Standards and such. I would venture to guess that most of the people involved in the ASTM Standards/Guidelines committees are Guardians (SJs). They would have a need for some sort of order established by a well respected institution, ASTM in this case.

I, personally, do not care for standards such as those from ASTM. But, I also think they serve a purpose, for those people who need some sort of structure. The development of such rules is neither good nor bad as long as one is not bound to them as in a "Standard" but are used as "Guidelines."

What I have presented in this write up are generalities and preferences. I am sure there are exceptions to each of the examples presented above. These are just my opinions based on personality analysis, my observations, and my experience. I expect that some of you will disagree with this analysis.

6 February 2000

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