Decision Making
Features and Classes of Decision Making
• Decisions typically represent a “manyto-one” mapping of information to
responses.
• The complexity of the choices can be
varied
– go – no go
– multiple choice response
Features of Decision Making: Uncertainty
• Uncertainty of the consequences.
• A result of the probabilistic nature of
the world – in which choices will lead to
outcomes.
• Always an element of “risk”
Features of Decision Making:
Familiarity and Expertise
• Decision making between “Experts”
and “Novices”
• Levels of Experience and Training
• Remember – experience might affect
the speed at which a decision is made –
not necessarily whether it was a good
one or not.
Features of Decision Making: Time
•
Time plays at least two important
roles in influencing the decision
making process:
1. One shot decision vs an evolving
decision
•
Purchasing an object
2. Time Pressure – element forcing timelines of a decision
•
Defusing a bomb!
Classes of Decision Making
• Cognitive or Information Processing
– Limitations in human attention, working
memory, strategy, heuristics – work well
together most times
• Naturalistic Decision Making
– How people make decisions outside the
laboratory environment
– Aspects of expertise, complexity
Characteristics of
Decision Making
1. Expected Value
i.
The optimum decision would produce
the maximum value if repeated
numerous times.
ii. Often the “value” is not universally
agreed upon (personal worth or
experience)
iii. Is the value minimizing the expected loss
or maximizing the expected gain
Characteristics of
Decision Making
2. Good decisions produce good
outcomes
i.
Sometimes it is only hindsight that let’s
us know whether the decision produced
the desirable results
Characteristics of
Decision Making
3. Good decisions are made by
“experts”
i.
Sometimes novices can make better
decisions – an “expert” decided to go on
the Challenger launch.
Evidence Accumulation
• Cue Diagnosticity
– How much evidence a cue offers
• See rain drops you know it is raining
• Dark clouds on the horizon – maybe it will rain
• Cue Reliability or Credibility
– The likelihood a physical cue can be believed
• Peter and the Wolf
• Physical Features of the Cue
– Is it conspicuous
– How much perceptual attention does it attain
Attention and Cue Integration
• Information Cues are MISSING
– Not enough information on hand to make an accurate
decision
• Cues are Numerous: Information Overload
– Less than perfect information value
– Lack of expertise
• Cues are Differentially Salient
– Attention-attracting properties and subsequent meaning
• Processed Cues are Not Differentially Weighted
– Modulate the amount of weight given to a cue
Belief Changes Over Time
• Overconfidence Bias
– The decision to seek more information before making a
decision (decision within a decision) occurs with levels of
uncertainty. However, research indicates that people are
overconfident in their state-of-knowledge or bias.
– Prematurely close the search for evidence.
• Anchoring Heuristic
– Humans have a tendency to bias beliefs in favour of the
initially chosen hypothesis – mental anchor – fixed
paradigm.
• The Confirmation Bias
– A tendency for people to seek information and cues that
CONFIRM the tentatively held hypothesis or belief.
Stress
• STRESS and ERRORS are linked in a
closed loop system…
• When errors are made (and we become
aware of them) stress occurs; and
when stress is present, errors occur.
*
External
Internal
* An experience whose essence is arrived through the analysis of living
experience in disregard of scientific knowledge; something known
through sense perception rather than by thought or intuition.
Stress Component Effect
• One of the best ways of integrating the
effects of stress on performance is to
consider their influence on the information
processing component.
• Recall, what are some of the processing
components:
–
–
–
–
Selective Attention
Working Memory
Response Choice
Dependence of task on particular components
Arousal
Stressors can mediate the sympathetic nervous system
Can use physiological responses
as an “indirect” measure of stress
Selective Attention: Narrowing
• As discussed, changes in human selective and focused
attention mediate many stress effects.
• One of the most important and robust appears to be an
increased selectivity or “attentional narrowing” that results
from a wide variety of different stressors.
• Tunneling is not simply defined by a reduction of the spatial
area of the attention spotlight but can be caused by a filtering
effect from operator priority.
• Sometime this narrowing can improve performance, but often
degrades response as only central tasks are attended to and
peripheral events can be ignored.
Selective Attention: Distraction
• Many stressors impose a distraction
and this divert selective attention away
from task-relevant processing.
• Loud or intermittent noises will serve
as a source of distraction.
Working-Memory Loss
• Noise, danger, anxiety will all degrade
working-memory capacity.
• There is a disruption of the “inner speech”
necessary to carry out rehearsal.
• These effects of these cues are then
degraded as well.
• Will effect how new experiences are
“encoded” into long-term memory.
Yerkes Dodson Law
Perseveration
• High levels of stress will cause people to
persevere or continue with a given action or
plan.
• This leads to trying to repeat the
unsuccessful solution (the very failure which
might be creating the stress on the operator).
• Familiar behaviour is little hampered but
more novel behaviour becomes disrupted.
Strategic Control
• Recruitment of More Resources
– “try harder”
– Risks are increased fatigue then subsequent problems
• Remove the Stressor
– Turn off the alarms
– Eliminate the “time pressure”
• Change the Goals of the Task
– Are multiple options available
• Do Nothing
– Do nothing to adjust their processing strategy allowing the
stress effects to influence the performance in a more
predictable manner.
Categories of Human Error
Mistakes
• Knowledge-based mistakes
– Incorrect plans of action are arrived at because of a failure
to understand the situation.
• Biases and Cognitive Limits
• Level of Expertise
• Rule-based mistakes
– Occur when operators are somewhat more sure of their
ground so they invoke a rule (if-then logic).
– Good rule is misapplied
– Choice of rule is guided by frequency and reinforcement
– Compared to knowledge-based mistakes, rule-based
mistakes are performed with much more confidence
Slips
• In contrast to mistakes, in which the
intended action is wrong, slips are
errors in which the right intention is
INCORRECTLY carried out.
– Pouring orange juice on your cereal
instead of milk because you were busy
reading the paper.
Lapses
• Represents the failure to carry out any
action at all.
• Forgetfulness
• Omission to carry out all the steps due
to some interruption during routine.
Mode Errors
• When a particular action that is highly appropriate in
one mode of operation is performed in a different,
inappropriate mode because the operator has not
correctly remembered the appropriate context.
• Generally a consequence of highly automated
performance or of high workload.
• Thinking you are in a reverse gear when you are in a
forward gear and then stepping on the accelerator.