Have you ever come across someone who simply refuses to acknowledge facts when they don’t suit their argument?
Chances are if you’ve debated matters of politics, religion or science, even with friends or family members, you’ve come across bias – an inclination that prevents people from accepting those facts they don’t like.
To some degree everyone suffers from bias, whether they know it or not. Scientists are trained to be aware that their own biases can prevent them from finding the truth, and the scientific method helps them reduce the risk of bias from their results as much as possible.
But not everyone is so careful. One famous study (Hastorf & Cantril, 1954) asked football fans from different colleges to watch a game of (American) college football. The game was quite rough and the umpires had to make a number of controversial calls.
When asked about the game, the fans didn’t give objective answers. Those from Princeton were convinced that the other team was breaking the rules, but those from Dartmouth were equally convinced that the other team was in the wrong. This study and many others finds that people process and recollect things in concert with their beliefs and attitudes, whatever they may be.
For the “thing” simply is not the same for different people whether the “thing” is a football game, a presidential candidate, Communism, or spinach.
(Hastorf & Cantril, 1954, p. 133)
But do these biases affect some people more than others?
With just a cursory look at social media you’ll find accusations of bias being thrown around almost whenever two people disagree. But perhaps there is no other subject area where this happens quite like politics.
So Ditto et al (2018) delved into the published science to find out whether right-leaning people are more or less biased than their ideological opponents.
They found 51 studies with a total of 18,000 participants that looked into whether conservatives or liberals were more accepting of information that they already agreed with or were more dismissive of information that challenged their existing beliefs.
And they found that there was no significant difference between the two. There was a modest partisan bias for both. And it didn’t matter whether that information was of a scientific nature or not, it was generally dismissed if they didn’t like it.
The clearest finding from this meta-analysis was the robustness of partisan bias. A tendency for participants to find otherwise identical information more valid and compelling when it confirmed rather than challenged their political affinities was found across a wide range of studies using different kinds of samples, different operationalizations of political orientation and political congeniality, and across multiple political topics.Ditto et. al. (2018), p. 10
So the next time you’re having a debate with someone about something like politics consider that you are probably just as biased as they are. As the authors conclude, “… a crucial first step is to recognize our collective vulnerability to perceiving the world in ways that validate our political affinities.”
- Ditto, P. H., Liu, B. S., Clark, C. J., Wojcik, S. P., Chen, E. E., Grady, R. H., … Zinger, J. F. (2018). At Least Bias Is Bipartisan: A Meta-Analytic Comparison of Partisan Bias in Liberals and Conservatives. Perspectives on Psychological Science. https://doi.org/10.1177/1745691617746796
- Hastorf, A. H., & Cantril, H. (1954). They saw a game; a case study. The Journal of Abnormal and Social Psychology, 49(1), 129-134.