In our sports-crazed world it’s easy to find people who practically live and die by their team’s victories and defeats. If you ask them who the best team in the league is, or who their favorite athlete is, no surprise! It’s their home team and their team’s superstar. For the most part everyone knows this is a harmless bit of fun — of course I’m biased to think that my team is the best! Out in the real world, though, biases are not so obvious and can have real-life negative consequences.

Writing for Psychology Today, Christopher Dwyer, Ph.D. reflects on a study conducted in 1999 by psychologists David Dunning and Justin Kruger. “For those of you unfamiliar with the phenomenon,” Dwyer writes, “the Dunning-Kruger Effect refers to a cognitive bias in which individuals with a low level of knowledge in a particular subject mistakenly assess their knowledge or ability as greater than it is. Similarly, it also refers to experts underestimating their own level of knowledge or ability.”

Everyone makes everyday decisions based on cognitive biases for the simple reason that it’s efficient to do so. You can’t process every bit of information before you make a simple decision so we unconsciously use mental shortcuts to take action — shortcuts which can include cognitive biases. Unfortunately, a cognitive bias can also be an unconscious pattern of error in thinking that isn’t quite rational, which leads to irrational decisions.

Because the subject of cognitive bias generates a lot of interest, and because information quickly delivered through social media is affecting our biases, Dwyer put together a list of common biases we encounter every day. These include:

Confirmation Bias. This may be the most well-known of the cognitive biases generally discussed. It may also be the most relevant today because we are confronted daily with an online world where algorithms are designed to feed us information that confirm our existing beliefs — almost the dictionary definition of confirmation bias. That’s why it’s more important than ever to consider both sides of an issue before we take action.

Self-Serving Bias. Getting back to a sports analogy, who hasn’t blamed a loss on terrible calls from a referee or umpire? And who hasn’t reveled in the joy of a win even though the same referees or umpires are in the game? This is a tendency to engage in the all-too-common self-serving bias. As Dwyer says, “We attribute successes and positive outcomes to our doing, basking in our own glory when things go right; but, when we face failure and negative outcomes, we tend to attribute these events to other people or contextual factors outside ourselves.”

Optimism/Pessimism Bias. This bias goes right to the heart of human nature. When we’re feeling good, then all is right with the world and every decision we make is going to be brilliant. When we’re feeling down, the opposite is true: we think this will never work! A good rule of thumb with this in mind: avoid making decisions when you’re really high or really low without taking a step back and trying to think objectively.  

Negativity Bias. Pessimism bias has a cousin: negativity bias. It’s actually based on another aspect of human nature that research has shown to be prevalent: Even though we like to win, our aversion to losing is even stronger. “So, when we make a decision,” Dwyer says, “we generally think in terms of outcomes —either positive or negative. The bias comes into play when we irrationally weigh the potential for a negative outcome as more important than that of a positive outcome.”

In-Group Bias. It’s interesting to explore how much of our behavior is driven by our intrinsic human nature that has developed over millennia in order to help us survive. One such behavior is to favor people within our own tribe or group. That’s why it takes some effort to be kind and fair when we’re judging actions of people outside of our group.

Dwyer explores more biases in his article but the larger point is that some self-reflection might go a long way in helping you make good decisions about important issues that have significant consequences.