Really?
I
think for the statement "all accidents are preventable" to become
REMOTELY true (ish) we will need to add some words. For example:
All accidents are preventable... with the benefit of hindsight.
or
All accidents are preventable... in theory.
or
All accidents are preventable... given unlimited knowledge, resources, perfect
prediction (and quite some luck).
All of which, regrettably makes it a rather useless statment in my everyday
job. And besides, do we really want to prevent absolutely everything? Really??
donderdag 24 april 2014
dinsdag 1 april 2014
Gerd Gigerenzer - Gut Feelings - Short Cuts To Better Decision Making
This book
was on my “things to do” list for quite a while (triggered by Gladwell’s
“Blink” and Gigerenzer’s “Risk” book) and went substantially up to the top of
the list after “Antifragile” and Taleb’s promotion of heuristics. It’s very
compact, almost 230 sides of easy to read (and often even slightly humorous)
text.
The first
part of the book is titled “Unconscious Intelligence”. We think of intelligence
as deliberate, conscious activities guided by the laws of logic. Much of our
mental activities, however, are unconscious and driven by gut feelings and
intuitions without involvement of formal logic. Our mind often relies on the
unconscious and uses rules of thumb in order to adapt and economize. One reason
it needs to do so is because there is only so much information we can digest at
one time.
One
advantage is that these simple rules are less prone to estimation and
calculation error and are intuitively transparent as opposed to complex models.
So, an intuitive shortcut, or heuristic, often gets us where we want without a
smaller chance of big errors, and with less effort. Gigerenzer says therefore
that it’s not a question if but when we can trust our intuitions.
One example
for this that an experienced chess player will usually generate the best
solution first and he will not do better with more time to reflect and
reconsider - rather in contrary. Inexperienced players on the other hand will
most of the time benefit from long deliberation. So, stop thinking when you are
skilled. Thinking too much about processes we master (expertly) will usually
slow down or disrupt performance as everyone who has tried to think about going
down the stairs can confirm. These things run better outside our conscious
awareness, so more is not always better.
Heuristics
try to react on the most important information, ignore the rest and lead to
fast action. Heuristics are a result of evolved capacities of our brain: simple
rules are developed over time and thanks to practice we are able to perform an
action really quickly and well - effective and efficient. The selection of the
applicable rules is unconscious. Gigerenzer thus views our mind as an adaptive
toolbox with rules of thumb that can be transferred culturally or genetically
and also developed by ourselves, or adapted from existing rules.
One
function of intuition is also to help us master one of our main challenges: we
don’t have all the information, so we have to go beyond the information that is
given to us. Out brain often “sees” more than our eyes by “inventing” things in
addition to what in fact is seen, like depth (a ‘third dimension’) in a (2D)
drawing.
If a gut
feeling will have the wanted/correct outcome depends upon the context it’s used
in. So a heuristic is neither good nor bad, this depends upon the environmental
structures. Selection of rules of thumbs can be triggered by the environment
(‘automatic rules’) or selected after a quick evaluation; conscious or (often)
not. If the first chosen of the latter category ‘flexible rules’ doesn’t work
another is selected. Gut feelings may seem simplistic, but their underlying
intelligence is selecting the right rule of thumb for the right situation
(depending on circumstances, environment, etc).
It’s
perceived wisdom that complex problems demand complex solutions. In fact,
however, in unpredictable situations the opposite is true. As things are, our
world has limited predictability. Keeping that in mind one may consider that we
should spend less resources and money on making complex predictions (and on
consultants who make them for us). In hindsight a lot of information may help
to explain things and it’s easy to fit information to past events. In order to
predict the future, however, much of the information one gets is not helpful in
predicting and thus it’s important to ignore the information that is not of
value. The art of intuition is to ignore everything except the best clue that
has a good chance on hitting that useful information. Psychological research
suggests that people often (but not always!) base intuitive judgments on one
single good reason. (do check pages 150 and 151!).
The final
chapter of part one discusses intuition and logic. It starts with the famous
‘Linda problem’. Criticizing Kahneman et.al. Gigerenzer argues that calling the
intuitive solution of most people a fallacy is not correct because gut feelings
(or humans in general) are not governed by the rules of mathematical logic. He
says that the human brain has to operate in a uncertain world, not in the
artificial certainty of a logical system. Our brain has to make sense of
information given and go beyond it. It zooms in on certain parts that seem particularly
relevant within the context and it views words (like ‘probable’) in their
common use and conversational meaning rather than in a formal academic/logical
sense. Gigerenzer sees heuristics as a way to success rather than as a cause
for error.
I find that
there are arguments for both ‘sides’. Humans are bad with probabilities and
numbers (something which Gigerenzer addresses in his other book, by the way)
but humans don’t operate necessarily to the rules of formal logic - as anyone
can confirm who has seen humans in action. An interesting thing to think about
and keep in the back of your mind.
Gigerenzer
concludes that logical arguments may conflict with intuition, but that
intuition is often the better guide in the real world. Nevertheless many psychologists
treat formal logic as the basis of cognition and many economists use logic as
the basis for ‘rational’ action. This isn’t how the world works, however, and
logic is blind to content and culture and it ignores environmental structures
and evolved capacities. Gigerenzer closes by stating that good intuition must
go beyond information given and therefore beyond logic.
Part two is
called “Gut feelings in action” and discusses a couple of real-life examples of
intuitions. It starts with the functions of recognition (a very strong memory
function of our brain) and recall (not so strong, especially with age).
Recognition helps us to separate the old from the new. The recognition
heuristic can help us making intuitive judgments, like when someone who knows
nothing about football is asked what team will win, he will probably pick the
best known, and more often than not be right. This means that in some cases
ignorance even can be beneficial because more knowledge may mean that one
cannot rely on this heuristic anymore. One remarkable fact is that during tests
people who relied on the recognition heuristic made snap decisions which
appeared to impress people with greater knowledge who needed time to reflect.
The
recognition heuristic is an example of a flexible rule which is chosen by our
unconscious intelligence after an evaluation process. It can be overridden
consciously in several ways. Another
example of ‘one reason’ decisions is the way that political preferences are
commonly ranged on a left-right scale, even if the subject at hand is totally
unrelated to the left-right opposite.
Not always
do we rely on just one reason, often we make intuitive judgments based on evaluation
of a sequence of cues that are evaluated, but again only one determines the
final decision - so called sequential decision making. We go through a series
of cues (most important first, second next, etc) and evaluate options. As long
as options ‘score equal’ we continue evaluating, but at the first cue where one
option is best we stop. We don’t evaluate all pros and cons to find the optimal
solution rather we choose the ‘first best’. Sequential decision making based on
the first good reason is very efficient, transparent and often more robust and
accurate than complex models.
One tool
for sequential decision making is a ‘fast and frugal tree’ which through a
couple of yes/no questions leads to a quick decision, rather than working
through a huge, complex complete decision tree. Fast and frugal trees have
three building blocks: 1) a search rule that looks up factors in order of
importance, 2) a stop rule that stops looking further if a factor allows so,
and 3) decision rule that classifies an object. Among
others medical services use these ‘developed intuitions’ for making diagnoses.
These simple, transparent empirically informed rules help making better
decisions.
The last
two chapters deal with moral behavior and social instincts (e.g. imitation and
trust). People do morally unbelievable things (like the example of a WW II mass
murder illustrates) because of their reluctance to break group order. Peer
group pressure (consciously or not) is enormous and it may even overrule deeply
rooted moral instincts like “You shall not kill”.
One
important heuristic to understand is that people will usually opt for the
default (chose by the environment, or ‘system’) instead of making a conscious choice
- as is illustrated by the differences in percentages of organ donors between various
countries. By understanding the process and framing instructions or requests
well, one may be able to steer things in a desired (and preferably morally
just) direction.
This
summary/review obviously only scratches the surface of themes treated in this most
recommended book. Hope I tickled your interest, now go and read it for
yourself.
I’ve read
the Penguin pocket version ISBN 978-0-141-01591-0
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