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Congruence bias

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Congruence Bias describes how, as a species, we prefer to test exclusively against our initial premise, ignoring the possibility of other results.

To put it another way, Congruence Bias is about Testing to confirm your hypothesis (direct Testing) rather than trying to refute it by examining other assumptions.

Table of contents:
  1. What is Congruence Bias?
  2. Definition of Congruence Bias
  3. Implications for conversion rate optimization
  4. Congruence Bias in Retail
  5. Why is Congruence Bias Problematic?
  6. An Example of Congruence Bias
  7. Congruence Bias and How to Avoid It
    1. A/B Testing
    2. What if I Did the Opposite?
    3. ABT - Always Be Testing
  8. Conclusion

Congruence Bias describes how, as a species, we prefer to test exclusively against our initial premise, ignoring the possibility of other results.

To put it another way, Congruence Bias is about Testing to confirm your hypothesis (direct Testing) rather than trying to refute it by examining other assumptions.

What is Congruence Bias?

Congruence Bias is a type of confirmation bias in which people conduct experiments to support their initial ideas rather than examining other options. It is the act of doing tests to show yourself correct rather than incorrect.

Definition of Congruence Bias

Congruence bias is a human propensity to rely too much on direct Testing of a hypothesis while overlooking indirect Testing. It's comparable to confirmation bias in that individuals are more likely to test what they believe is the problem rather than items they enjoy or presume aren't.

For example, a registration page with a picture above the form, an offer banner, and a lengthy form with a grey backdrop may be evaluated. One optimizer could believe that removing the image will increase conversion rates. As a result, they erase the picture, which boosts conversion.

However, they don't experiment with deleting the offer banner, shortening the long-form, eliminating the grey backdrop to boost contrast, or leaving the image alone. If they tried making the other adjustments while keeping the picture, the theory would be disproved if the conversions increased even more.

Implications for conversion rate optimization

Our thoughts might be so dominated by the congruence bias that we fail to see other hypotheses to explore. This may be seen when companies regularly focus on testing the same things and designers come up with concepts identical to what they've done before. Frequently, the elements that aren't challenged, such as brand rules, provide the most room for development.

Don't only establish a single hypothesis while evaluating a screen or user experience. Make sure you come up with as many alternative ideas as possible and attempt to develop theories for portions of a page that you don't think are troublesome. Congruence bias can be mitigated by performing the latter. However, avoiding the consequences of congruence bias requires an organized strategy to optimization that involves acquiring ideas from consumer research and usability testing.

Congruence Bias in Retail

The bulk of data used by brands and merchants in retail is based on sales. That is, the information analyzed is primarily dependent on what was sold. However, are marketers and retailers missing specific important indications by testing directly to validate the sales hypothesis? The Congruence Bias may be constraining; here are a few key, alternative aspects that are frequently overlooked in data:

  • Attention: How many buyers see your brand when they go inside a store?
  • Appeal: What proportion of folks who view your brand finds it appealing?
  • Engage: How many people in the shop who see your brand and find it appealing engage with it on the shelf?

When you analyze sales data in terms of attention, appeal, and engagement, you may not only see where your most numerous possibilities are, but you can also improve every stage of the process. You are more than likely to boost sales due to increasing any Attention, Appeal, or Engagement.

Why is Congruence Bias Problematic?

Congruence bias occurs when you strive to confirm pre-existing theories or ideas rather than find the optimal answer. This generally indicates you're attempting to prove yourself correct, leaving you with tunnel vision and oblivious to better viable solutions that exist all around you; you can wind up neglecting a more effective solution or disregarding the actual cause for changes in consumer behavior.

An Example of Congruence Bias

Two identical objects with different packaging are shown to a person. You hypothesized that customers would prefer packaging with human images over packaging with drawings; therefore, you declare success when the data reveal that the packaging did better! But were you correct in doing so? Most likely not. Although shoppers may have favored human imagery, photos of youngsters rather than adults may be more successful. By succumbing to Congruence Bias, you may have shortened your testing duration, and, as a result, you may not be maximizing the potential of your packaging owing to a lack of other choices.

According to drug rehab studies, high school pupils who use marijuana are more likely to go to harsher substances like heroin and methamphetamine. This erroneous notion stemmed from a poll of drug users who were asked what their first substance was. Many people said they began with marijuana. On the surface, this seems reasonable. However, the survey question was incorrect. It didn't look at other factors that may have led to the use of heavy drugs. The researchers stopped exploring for additional explanations only because heavy drug users mentioned cannabis in the past (Congruence Bias). The belief was that because marijuana was a horrible hippy young person substance, it must have been the catalyst for heavy drug usage. It was statistically sound, as a substantial percentage of heroin addicts reported it. However, it was inaccurate.

Carrots were consumed by nearly all heroin addicts when they were children. However, we do not believe that carrots induce heroin abuse. Carrots don't "feel" like a reasonable response; thus, they wouldn't be included in the experimenters' cognitive bias. Keep in mind that bias is prejudice in favor of or against something. The issue is that the researcher is often unaware of the discrimination. Cigarettes, according to a later study, are the gateway drug to heavy narcotics. Young smokers' "screw you" attitude appears to be a stronger predictor of future hard drug usage.

Congruence Bias and How to Avoid It

More trials are required! You must, of course, test your hypothesis. But don't rest on your laurels. It would be best if you also tried to refute your theory or explore alternate approaches.

A/B Testing

The process of testing two different hypotheses and comparing the outcomes is known as A/B Testing. A/B Testing, for example, may have remedied the problem with the landing as mentioned earlier page. You could have put both ideas to the test, and it would have become evident that the layout modification is the better option. This would eliminate any congruence bias that could be present.

What if I Did the Opposite?

Hypotheses can often appear so evident that an alternative seems unthinkable. Congruence bias is at its most pervasive at this moment. One of the most effective ways to overcome this is to question yourself, "What if I did the opposite?"

This quickly presents a concept that you probably hadn't considered previously. Most of the time, this test will confirm your initial theory, but it might also out to be incorrect.

I used to write in hour-long chunks of time, for example. I'd take my time, worrying over each word and sentence and revising as I went. But one day, I decided to try something completely different. I tried writing for ten minutes straight with no editing. I discovered that I was able to create far more work of more excellent quality than usual.

Other ideas include exercising first thing in the morning instead of later in the day, not checking your email for 24 hours, working outside, and just reading fiction novels for a week.

ABT - Always Be Testing

In conclusion, you may prevent congruence bias by ensuring that your assumptions are tested, particularly when the most logical.

See what happens if you change things around for a day or simply an hour. Worst case scenario, you now have further proof that you were correct all along.


Congruence bias is harsh for solo optimizers since we might get stuck in our ways and overly focused on our notions about what needs to be changed on a website or app.

When we work closely with designers, developers, marketers, UX, and other teams to bring together ideas from various individuals, we can achieve the best results. Furthermore, adopting a systematic optimization process will aid in the avoidance of congruence bias by encouraging evidence-based decision-making. Congruence bias may be avoided by doing a thorough study and analysis.

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