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We think we are smart, but understanding Cognitive Biases shows how limited is our perception of reality and information around us.
On this presentation I expalin and bring some real examples of the most commom biases used in the market, web and UX.
There are many kinds of cognitive biases that influence individuals differently, but their common characteristic is that they lead to judgment and decision-making that deviates from rational objectivity.
A dive into Cognitive Biases
Systematic ways in which the context and
framing of information inﬂuence individuals’
judgment and decision-making.
There are many kinds of cognitive biases that
inﬂuence individuals diﬀerently, but their
common characteristic is that they lead to
judgment and decision-making
that deviates from rational objectivity.
In some cases, cognitive biases make our thinking
and decision-making faster and more eﬃcient.
In other cases, however, cognitive biases can lead
to errors for exactly the same reason.
The reason is that we do not stop to
consider all available information, as our
thoughts proceed down some channels instead of
others - our attention is limited.
There is just too much information in the
world, we have no choice but to ﬁlter
almost all of it out.
Our brain uses a few simple tricks to pick
out the bits of information that are most
likely going to be useful in some way.
• We notice things that are already primed
in memory or repeated often.
• Bizarre, funny, visually-striking,
anthropomorphic things stick out more
than non-bizarre/unfunny things.
• We notice when something has changed.
• We are drawn to details that conﬁrm our
own existing beliefs.
• We notice ﬂaws in others more easily
than ﬂaws in ourselves.
The world is very confusing, and we end up
only seeing a tiny sliver of it, but we need
to make some sense of it in order to survive.
Once the reduced stream of information
comes in, we connect the dots, ﬁll in the
gaps with stuﬀ we already think we know,
and update our mental models of the world.
• We ﬁnd stories and patterns even in
• We ﬁll in characteristics from
stereotypes, generalities, and prior
histories whenever there are new speciﬁc
instances or gaps in information.
• We simplify probabilities and numbers
to make them easier to think about.
• We think we know what others are
thinking. In some cases this means that
we assume that they know what we know.
• We project our current mindset and
assumptions onto the past and future.
We’re constrained by time and information,
and yet we can’t let that paralyse us.
With every piece of new information, we need
to do our best to access our ability to aﬀect
the situation, apply it to decisions, simulate
the future to predict what might happen
next, and otherwise act on our new insight.
• In order to stay focused, we favour the
immediate, relatable thing in front of us
over the delayed and distant.
• In order to get anything done, we’re
motivated to complete things that we’ve
already invested time and energy in.
• In order to avoid mistakes, we’re
motivated to preserve our autonomy and
status in a group, and to avoid irreversible
• We favour options that appear simple or
that have more complete information
over more complex, ambiguous options.
There’s too much information in the universe.
We can only aﬀord to keep around the bits that
are most likely to prove useful in the future.
We need to make constant bets and trade-
oﬀs around what we try to remember and what
For example, we prefer generalisations over
speciﬁcs because they take up less space.
• We edit and reinforce some memories
after the fact
• We discard speciﬁcs to form generalities.
• We reduce events and lists to their key
elements. It’s diﬃcult to reduce events
and lists to generalities, so instead we pick
out a few items to represent the whole.
• We store memories diﬀerently based on
how they were experienced.
The availability heuristic explains why people think ﬂying is unsafe, because a plane crash
comes much more readily to mind when compared to a safe ﬂight. It's why people fear
shark attacks too, even though you're statistically more likely to come to your end because
of a champagne cork than because of a shark attack.
Even though a $50 note has the same value as 5 x $10 notes,
we will invariably spend the lower value notes before we even
think of touching the $50.
“When physicians receive gifts from pharmaceutical
companies, they may claim that the gifts do not aﬀect their
decisions about what medicine to prescribe because
they have no memory of the gifts biasing their prescriptions.
However, if you ask them whether a gift might
unconsciously bias the decisions of other physicians,
most will agree that other physicians are unconsciously
biased by the gifts, while continuing to believe that their
own decisions are not.
This disparity is the bias blind spot, and occurs for
everyone, for many diﬀerent types of judgments and
Senior UX Designer