Understanding the Theory: Holland's Codes
In the 1970s John Holland developed a popular theory of interest development based around these six personality types:
1. Realistic (R)
These are people who like well-ordered activities, or enjoy working with objects, tools, and machines.
Realistic people:
See themselves as mechanically or athletically talented, but may not be good with people.
Value concrete and tangible things like – money, power, and status.
Avoid "social" activities, those that need interaction with other people.
Common traits:
Hard-headed, inflexible, persistent, materialistic, practical, and genuine.
2. Investigative (I)
Investigative people like activities that involve creative investigation of the world or nature.
Investigative people:
See themselves as highly intelligent, but often lack leadership skills.
Value scientific endeavors.
Avoid activities that seem mundane, commercial or "enterprising".
Common traits:
Analytical, curious, pessimistic, intellectual, precise, and reserved.
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