Behavioral finance FAQ / Glossary (A)
Ac - Ad
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Year/month, d: developed / discussed, i: incidental
Accumulation / Distribution
00/8i,12i + see distribution / accumulation,
congestion / (price) cluster, percolation + bfdef3
Active / passive investing
Because of its length, this article is in a
separate page
of this "A" section of the Glossary
Adaptation / Adaptable / Adaptive (system, economics, market)
02/10i - 04/9i - 05/2i - 06/4i + see dynamical systems,
evolutionary economics, chaos theory, percolation
Addiction
00/10i,12d + see overtrading, commitment, willpower,
habit, automaticity
How to resist it?
Definition
Addiction is a recurrent
compulsion, due to a mind
dependence
(in its extreme forms categorized as a pathology), which overcomes rational thinking
and causes actions that bring damages to the person affected, and sometimes to others
Stock trading can become addictive and thus be a psychological disorder like any other.
This could result in "noise trading" / "overtrading" (see those words) which entails:
For the trader, high risks and costs.
In the market, return and price anomalies.
At least if the contagion spreads (see herding) to many investors and is exacerbated by greed or fear.
(under- / slow) Adjustment
Because of its length, this article is in a
separate page
of this "A" section of the Glossary
Administration / administrative behavior
04/9i + see corporate behavioral finance,
public choice, principal-agent
Af - Ag
Dates of related message(s) in the Behavioral-Finance group (*):
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Affect, affect heuristic
03/6i + see emotions, sentiment, mood, attitude,
heuristic, automaticity, trust
I love it!
I hate it!
Definition (affect): The affect is the conscious part of an emotion (see that word).
Emotions, based on pain and pleasure, are factors in many decisions.
Definition (affect heuristic):
An affect heuristic is a quasi automatic emotional response / reflex (see automaticity bias) or decision,
which is linked to:
The decider's love / hate, or liking / dislike of something or somebody,
Or his / her mood (see that word), when feeling happy or unhappy.
The person might label its attitude as "instinct", whatever the real nature of the stimulus that influences it.
This emotional behavior might to be illusory and go against rationality.
This can be compounded by the fact that emotions (see that word) tend to have a primacy over reasoning.
A doctor, lawyer or detective is hardly neutral when a case is about a member of its family.
For investors, the affect heuristic can cause a home bias (see that word), a trust in what is familiar.
Examples in
investing
Swindlers can take advantage of the (positive) affect heuristic, as a factor of trust
A reason why Bernard Madoff was trusted by its victims is that it was considered as ...a nice guy.
This trust factor can also encourage clanism / groupthink / mimicry / herding, as a feeling of togetherness.
According to a well studied example, people, and among them investors, tend to feel more optimistic
when the sun shines!
They react or decide accordingly, for example they feel an impulse to consume or invest.
A good feeling towards a stock (positive affect) might lead to a lower risk perception
and a higher benefit perception,
This goes against common market experience by which high return prospects entail usually
a higher risk (see risk premium)
(principal-) Agent / Agency theory
08/i,8i,11i - 03/1i + see ethical, moral hazard,
perverse incentive
Agent-based model
01/5i - 03/2i,8i,9i,12i - 04/2i - 08/11i + see style
Let us pack all those people inside the computer and see what comes out!
In economics / finance, an agent-based model (or agent model) is a software that simulates
the actions (buying / selling) of several types of agents (professionals / general public, etc),
Application to
financial markets
Money-chasing clans in the hard drive
When the agents are investors, the simulation takes into account that each category
has its style /
profile / preference
(short term, long term, fundamentalist, "technicalist", follower, contrarian, etc...).
The aim of the simulation is to see how the
interactions between those clans
impact market prices, trends, returns, volatilities...
It would help to understand those phenomena, and if possible to predict them.
Those models might be better predictors of dramatic "non linear" disruptions and unbalances
than those working on standard mathematics equations. There is more "artificial intelligence" in
them, but of course they are worth only what their assumptions about behaviors are worth.
The snag is that human uncertainty is at play, thus surprises are always possible.
Therefore it is not too easy to predict how each category of agent will react to situations
without falling into caricatures.
Also, the relative weight of the various categories might evolve.
Those models are also one of the tools of microeconomics.
Whatever the difficulties involved, this rising branch of economics has the merit
to try to start from
field work and ground level realities
more than from large equilibriums between aggregate national or international data.
Al-Am
Dates of related message(s) in the Behavioral-Finance group (*):
Year/month, d: developed / discussed, i: incidental
Algorithmic trading
See system trading
Alpha coefficient (excess / insufficient return)
00/6d - 01/9i - 02/7i,8i + see (sector) rotation
Does the lottery wheel choose its winners and losers?
Definition: the alpha coefficient measures anomalous asset returns.
Those can be defined as returns that are - rather durably (not just accidentally) - above or below
what the standard theories (*) predict,
(*) Namely the CAPM and the RWH (see those acronyms) predict.
Let us remind that those theories consider that:
Only differences in
![]()
risk / volatility, or different "betas",
explain differences of
![]()
returns between assets.
The alpha coefficient appears in the CAPM equation,
but is theoretically equal or close to zero in that model.
Therefore, positive or negative" alphas", meaning excess or insufficient returns
that would be independent of the risk would be impossible,
Predictable alphas that would bring superior performances than the market would not exist either,
The random walk hypothesis says you cannot beat the market by predicting
the next price moves and returns.
But in practice,
History shows sizeable
positive or negative alphas,
in certain time frames, or in some sectors or stocks.
The past performances of fund managers in a given period are measured in alphas.
Here, alphas are extra or insufficient returns for their portfolios,
compared to the general market performance.
Usually a past performance in a past situation does not guarantee
a similar performance in a future situation,
but some - rare - people might recurrently have more skill (see luck vs. skill)
than the average player to adapt their practices.
Alternation (of trends)
00/6i,7d,8i + 01/11i + see cycle, trend + bfdef3
Altruism
08/6d, 09/6d + see ethics, needs, fairness, genetic utility
Moral incentives vs. money incentives.
Altruism, as an interest for other people more than for the self, should not be neglected as a motivation,
including in economics.
Altruism, and what they see as fairness or common good, can
make people do positive things that they would not do for money
This does not mean that all moral motivations and "good intents" bring always positive results.
Some can be overly emotional and self defeating, and sometimes manipulated.
Ambiguity aversion, ambiguity premium
01/2i + see uncertainty
An
Dates of related message(s) in the Behavioral-Finance group (*):
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(mental) Anchor / Anchoring
Because of its length, this article is in a
separate page
of this "A" section of the Glossary
(market) Anomaly
Because of its length, this article is in a
separate page
of this "A" section of the Glossary
Anticipation
Because of its length, this article is in a
separate page
of this "A" section of the Glossary
Ap - As
Dates of related message(s) in the Behavioral-Finance group (*):
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APT
See Arbitrage Pricing Theory
ARCH / GARCH models
00/6i,10d + see heteroskedasticity + bfdef3
(limited) Arbitrage
(absence of / limits of) Arbitrage opportunity
Arbitrage pricing theory (APT)
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Because of their lengths, those articles are in a
separate page of this "A" section of the Glossary
Archetype (stock, trader)
00/12i + see profiling, type, prototype, style
An archetype is a common traditional mental reference to represent ideally a given category
of things or phenomena (of stocks, of investors, for example...).
While "prototype" is used to describe a new design or phenomenon,
archetype refers to old examples, real or invented.
Both are found in finance: old categorizations as well as new paradigms.
Aristotle bias
See binary logic, narrow thinking, fuzzy logic, yin yang,
reductionism, stereotype
The Aristotle bias, or binary logic, is a reductive way
to categorize complex and gradual situations or concepts
as either 100% true or 100% false, 100% right or 100% wrong
Artificial Intelligence (AI)
00/7i + see soft computing, genetic algorithm, fuzzy,
non linearity, agent-based model
Asymmetry / skew
Because of its length, this article is in a separate page
of this "A" section of the Glossary
Att
Dates of related message(s) in the Behavioral-Finance group (*):
Year/month, d: developed / discussed, i: incidental
Attachment bias
See endowment effect
Attention anomaly, bias, disorder
Because of its length, this article is in a
separate page
of this "A" section of the Glossary
(common) Attitude
Because of its length, this article is in a
separate page
of this "A" section of the Glossary
Attractor
00/5d,11i,12d - 01/8i,11i
What if chaos were not totally chaotic?
Attractors
are a chaos theory concept that can be applied - metaphorically or directly -
to some phenomena detected by Behavioral Finance.
In
financial markets we may call attractor, in the broad sense,
any recurrent
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pattern of market or stock
behaviors - either biased or unbiased - that can be quantified.
Those patterns might be real or imaginary depending on circumstances.
Some real market phenomena seem to escape pure randomness and fit some pattern,
if not because of "laws of chaos", at least as a result of some behavioral biases
On the other hand, some precautions are needed so as not to "see" illusive patterns
(see representativeness heuristic) in all market evolutions.
Examples of "attractors" in finance
Trends, momentums, alternation/cycles,
Specific distribution curves of prices / volatility / returns,
Stock types,
Price levels,
Paradigms of valuation...
Attribution bias / error
00/9i,12i - 01/3i,5i - 02/2i,8i + see rationalization,
self attribution, deification / demonization, story + bfdef2
I am OK, you are not OK, or maybe more OK than OK.
Definition:
The attribution bias is the tendency to explain immediately a - pleasant or unpleasant - event,
without further analysis, by
attributing its responsibility (or at least its origin) to somebody,
to some organization or to some category of people.
That bias puts the blame, or the credit, on:
An identified person(s), for example the central bank president,
Or oneself (self-attribution, self-serving bias, group-serving bias).
For example, a random streak of luck in
financial operations, mostly when the market is favorable,
might be considered as due to one's own skill.
In its extreme form:
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A biased attribution can take the shape of
deification / demonization (see those words),
![]()
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A self-serving attribution might show
overconfidence or even narcissism (see those words).
The attribution bias can also be at play when people attribute a pattern
to some series or collections of events (see representativeness heuristic).
Au - Az
Dates of related message(s) in the Behavioral-Finance group (*):
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Automaticity, autopilot bias
Because of its length, this article is in a
separate page
of this "A" section of the Glossary
Availability bias, availability heuristics
See heuristic, primacy
Jumping on the first interpretation.
The availability heuristics is a cognitive bias using an oversimplified decision process based on how easily:
Information is found or recalled
(this gives a primacy to the most immediate, visible or easy to memorize one)
Or the causes or consequences of a situation are imagined.
See the "heuristic" detailed article.
Careful, you might be judged according to the first impression you give!
(disappointment, loss, risk, regret, uncertainty... ) Averse, Aversion
Aversion, disposition and prospects
Because of their lengths, those article are in a
separate page
of this "A" section of the Glossary
(*) To find those messages: reach that Behavioral-Finance group and, once you are there, 1) click "messages", 2) enter your query in "search archives".
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This page last update: 07/11/11
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