Skip to main content

Types of bias: A list of common cognitive biases


Simply put, a cognitive bias is a biased way of thinking that conflicts with logic and rationality. As much as we love to call ourselves rational, the truth is that the human psyche is loaded with numerous cognitive biases.

Being rational, therefore, is a continuous process of being aware of these biases and not letting them colour our perceptions, decisions, and judgments.

1) Choice-supportive bias

Your father prepares dinner, saying that he tried a brand new recipe. He assures you that you’ll have eaten nothing like it before. When you take your first bite, you realize it really is nothing like you've eaten before, but not in a good way. Everyone but your father feels the same.

“Come on! It's delicious! What’s wrong with your taste buds?” he empties his own plate in seconds trying to prove his point. 

Choice-supportive bias is defending and supporting your own choices, opinions, and decisions even if they have palpable flaws. Like many other biases, it's an ego thing. We identify with our decisions, perceiving an opposition to them as an opposition to us.




2) Pro-innovation bias

Innovation is, by all means, great, until it involves ego involvement, which it does quite often. This cognitive bias states that an innovator tends to overvalue the usefulness of his innovation and undervalue its limitations. Why shouldn't he? After all, it's his innovation.

3) Confirmation bias

We tend to expose ourselves only to information that confirms our belief systems. This cognitive bias is the most widespread and pervasive. Any information that shakes a person's belief system induces cognitive dissonance in him, rendering him psychologically unstable. Therefore, it is often met with vehement opposition.



4) Conservatism bias

Like the confirmation bias, it has to do with the maintenance of beliefs. It implies favoring prior information over new information because prior information supports our beliefs and new information may have the tendency to shatter them.

5) Bandwagon effect

You’re likely to hold a belief if it's also held by the majority. You’re like, “If so many people believe it, how can it not be true?”

But as philosopher Bertrand Russell said, “Even if a million people say a foolish thing, it's still a foolish thing”. Mark Twain made the point more amusingly, “Whenever you find yourself on the side of the masses, it's time to pause and reflect.”


6) Ostrich effect

Ignoring negative information by burying your head in the sand like an ostrich. It's a pain-avoidance mechanism. So-called ‘positive thinkers’ are usually prone to this type of bias. When something’s wrong, it’s wrong. Hiding from it doesn’t make it right nor does it mean it’s no longer there.

7) Anchoring bias

Let's say you’re negotiating a car deal and the car’s priced at, say 1000 currency units. The dealer expects you to negotiate around 1000 units, on the lesser side. So 1000 units is the anchor around which you’ll throw your bargains. 

You may get the deal if you pay 900 units because it is close to the anchor but if you insist on buying the car for 700 units, then success is unlikely because it's too far away from the anchor.

In this sense, an anchor is like a reference point around which we make our future decisions. In any negotiation, the person who first sets an anchor has the advantage of steering the deal in his favor
because it exploits our anchoring bias.

8) Selective perception

Our expectations, beliefs, and fears sometimes distort the reality that we see. 

Let’s say you’re unsure about your self-image because you’re wearing baggy pants that you hate. When you walk past a bunch of laughing people on the street, you might mistakenly perceive that they’re laughing at you because you're wearing odd-looking pants. In truth, their laughter may have nothing to do with you.

9) Overconfidence

Overestimating your knowledge and abilities. Experts are more prone to this type of bias because they think they ‘know it all’. Overconfidence is often the result of having many successful experiences behind you, to the point that you're blind to new possibilities or outcomes.

10) Stereotyping

Expecting a person to have the traits of a group to which he belongs. It enables us to quickly tell a friend from an enemy when we're encountering strangers. Sure stereotypes are there for a reason but it doesn’t hurt to get to know a person more before you can make an accurate assessment of his or her traits.

11) Outcome bias

Judging a decision based on the accidental positive outcome, despite the casual way in which the decision was actually made. 

Say you take a huge risk in gambling where you have a 50-50 chance of winning and losing. If you win, it’s going to be a big win and if you lose, it’s going to be a huge loss.

If you do actually win, you tend to believe post hoc that the decision was indeed a right one. In truth, it was just a toss-up. Had you lost your money, you’d be cursing your 'brilliant' decision.

12) Gambler’s fallacy

Another gambling bias, though a more insidious one. Here’s what you say when you're under the grip of this type of bias:

“I didn't win in all my previous attempts which means I’ll surely win in the next one because that’s how the laws of probability work.”

Wrong! If in a particular game, your chance of winning is 1/7, then it's 1/7 at the first attempt and it's 1/7 at the 7th attempt or even 100th attempt too. It’s not like probability is going to cut you some slack just because you tried 99 times!

13) Blind-spot bias

The tendency to spot biases much more in others than you do in yourself. If, while going through this article, you could only think of others who have such biases and not yourself, then you may have fallen prey to this type of bias.

The fact that I'm noticing a bias in you of noticing others' bias makes me think that I may have fallen prey to this bias too.


Follow latest posts by Email




Popular posts


Body language: Gestures of the head and neck

The head nod
Nodding the head almost everywhere in the world means ‘Yes’ and shaking the head from side to side means ‘No’. A slight head nod is used as a greeting gesture, especially when two people greet each other from a distance. It sends the message, ‘Yes, I acknowledge you’.

Body language: The truth of the pointing foot

When we communicate with others, our attention is focused mainly on the words they speak and the facial expressions they make. We pay little, if any, attention to gestures of the body and when it comes to the feet, we almost never look at them.

Body language: Clenching and clasping of the hands

Clenching hands in front of the body
This gesture has three main positions: hands clenched in front of the face, hands clenched resting on the desk or lap and, while standing, hands clenched over the lower abdomen.

Body language: Hands touching the head

Scratching the hair
When we scratch our hair using one or more fingers anywhere on top, back or side of the head, it signals the emotional state of confusion. Watch any student trying to solve a difficult problem and you are likely to observe this gesture. There isn't a better place to observe this gesture than an exam hall, where students often have no idea what the question paper is trying to say!

Body language: Crossing the arms

Crossing the arms across the chest is a classic gesture of defensiveness. This defensiveness usually manifests as uneasiness, shynessor insecurity.

What makes a person stubborn

Stubbornness is a personality trait in which a person refuses to change his opinion about a situation or refuses to change his mind about the action that he has decided to take.

Body language: Hands touching the neck

Rubbing the back of the neck
Ever seen two furry animals, like dogs, in a fight? If you have then you might have noticed that when they are about to attack each other, the fur over their neck stands on its end and makes the animals appear bigger. The bigger the animals appear the more they are able to intimidate each other.

How our past experiences shape our behavior and personality

Our beliefs and needs are the strongest factors that govern our behavior. Ultimately, it all comes down to beliefs because a need is also a belief- a belief that we lack something.

Body language: The crotch displays of men

When it comes to attraction, males and females use different signals to display their attractive qualities. 

Body language: Crossing the legs

Crossing the legs, like crossing the arms, indicates a defensive attitude. While arm-crossing is a subconscious attempt by a person to protect his vital organs- the heart and the lungs, crossing the legs is an attempt to protect the genitals.