of P’s needs are filled from within P. For example, the reinforcers’
“water,” attention and praise, come from E, but a feeling of accom-
plishment may depend on both E and P. This implies that P has some
self-reinforcement capability.
Skillmay be defined in terms of behavior sequences emitted in
response to a task. Skill varies on a number of dimensions: (1) repeata-
bility of the behavior sequence, (2) economy of effort (energy expen-
diture), (3) speed of performance (economy of time), and (4) difficulty
of the task. The last dimension—difficulty—is the dimension used
most often in scaling skill performance. The higher the level of diffi-
culty of the task that P is able to perform, the more proficient P is in
that skill. And the skills that P exercises more frequently—usually the
ones at which P is more proficient—become more stable and more
characteristic of P.
In PEC theory, a task is a response requirement,that is, a require-
ment for a desired response. P responds to a task by using its skills.
Task and skill (like need and reinforcer) can sometimes be circular
in definition; thus, a typing task requires typing skill, and typing
skill is defined by a typing task. In other instances, a task may
require more than one skill, and a skill may be used in filling more
than one task.
Tasks ordinarily originate with E, but P may also be the source of
some tasks (“self-imposed tasks”). Tasks vary from simple to complex,
requiring P to respond using skills ranging from simple to complex as
well. Complex skills are essentially combinations of simpler skills. In
response to the same complex task, however, different Ps may use dif-
ferent combinations of simpler skills.
Because a task is a requirement, it may be considered a kind of
need. This suggests that needs can be of two kinds: (1) reinforcer
(or reinforcement) requirements (the kind for which the term need
is most commonly used) and (2) response requirements, that is, the
needs for responses that are desired. In a parallel fashion, skills can
also be of two kinds: response capabilities (the kind ordinarily asso-
ciated with the term skill) and reinforcement capabilities, as dis-
cussed previously.
432 CAREER CHOICE AND DEVELOPMENT