The First Impression Bias

What is the First Impression Bias?

The first impression bias describes how we make quick judgements about others that are often subject to bias or error. The theory stems from the idea that humans are limited in their information processing abilities and will often rely on the first piece(s) of information they receive.

One Minute or Less to Make an Impression

The Basic Idea

Everyone wants to make a good first impression, whether it’s for a job interview or meeting a partner’s parents for the first time. But did you know that we have less than a minute to do so? Behavioral scientists call it the first impression bias: a limitation in human information processing that causes us to make quick and incomplete observations about others based on the first piece of information we perceive.9

First impressions are often very important, as they lead to quick assumptions and judgements. It takes as little as a tenth of a second or up to 30 seconds to make a first impression; moreover, there is much debate as to whether these impressions are even accurate. The first impression bias has implications for employment, relationships, ideas, business, and even medicine.

Your first impression of a thing sets up your subsequent beliefs. If the company looks inept to you, you may assume everything else they do is inept.

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Key Terms

Confirmation biasthe tendency to favour information that aligns with one’s own  beliefs or hypotheses, and disregard information that conflicts with these beliefs.2

Halo effecta cognitive bias wherein an initial positive impression of a person, brand, or product unconsciously influences our perception of them as a whole.5 For example, if you judge someone to be outgoing or attractive, you may also judge them to be more intelligent than they are.


Early research on the psychology of first impressions was focused almost exclusively on physical traits and personality, as attributes of the face were considered to be telling of a person’s character traits. In the 1700s, Johann Kaspar Lavater, a Swiss pastor, published a series of essays on how face features such as the shape of a nose and the closeness of eyebrows were important in determining a person’s intelligence, kindness, and perseverance. This information could then be used to determine if a person suited a particular occupation.12 However, this approach fell out of favor in the 19th century due to its similarity to phrenology, a pseudoscience that correlates measurements of bumps on the skull with personality characteristics.

Later work on first impression bias focused on how other cognitive biases, such as the halo effect and confirmation bias, perpetuate the first impression bias. The halo effect was discovered by Edward Thorndike, an American psychologist and early behaviorist, in 1920, but was not given its term until 1938 by S. M. Harvey.5  The confirmation bias was later described by Peter Wason in 1960, using the Wason’s Rule Discovery Test.2

More recent work has focused on first impressions’ role in different disciplines and across cultures. For example, Fang and colleagues (2020) found that national culture – the shared attitude or beliefs that separate members of one group from another – reduces first impression bias.4 Recall that the first impression bias can influence recruiters appraisal of a candidate; therefore, it seems that if national culture is shared among candidate and recruiter, the recruiter will not make assumptions about the candidates capabilities or character as they would with someone not of the same national culture.


The first impression bias can influence decision makers to place more weight on information first received, than information received later.7 This has many implications, but an interesting example of this exists among finance professionals. Hirshleifer and colleagues (2020) examined whether an analyst’s first impressions of a firm would induce bias in analyst forecasting behaviour. They found that finance professionals are prone to the first impression bias in their forecasts of the earnings for the firms that they cover. Specifically, Hirschleifer and colleagues found that if a firm performs well in the year before an analyst follows that firm, the analyst is optimistic in subsequent forecasts and vice versa. Further, this finding can carry over to price targets and recommendations. Notably, the first impression bias is not an isolated effect, but rather leads to the development of many subsequent cognitive biases such as the halo effect and the confirmation bias.

The Pygmalion effect occurs when someone else’s high expectations of us becomes a self-fulfilling prophecy, pushing us to do better. Learn more here.

The long-term implication of the first impression bias is referred to as the halo effect, which plays out when a positive first impression about one trait, such as beauty, leads people to infer the existence of other traits, such as intelligence. This effect is particularly problematic during hiring interviews, as it’s been estimated that wrong hires can cost a business one to seven times the person’s first annual salary.6 For example, consider an interviewer feeling a strong connection with a job candidate. Due to the halo effect, the interviewer is likely to believe this connection will translate into the workplace, and manifest as a hardworking and capable new hire. However, in reality, this new hire may have little actual experience and skills to perform the job and may have relied solely on their charisma in landing it.

Another consequence of the first impression bias is the development of confirmation bias, at work when people seek out information that confirms their pre-existing beliefs, and disregard information that conflicts with their beliefs. Succumbing to the confirmation bias has a laundry list of negative consequences across the board. It influences how researchers form hypotheses and design experiments, how readers consume and spread news, how businesses develop products, and even why people hold onto negative interpersonal relationships. For example, let’s consider a business developing a new product. The CEO proposes a new product idea and believes it will be wildly successful. She then directs her marketing research team to examine its feasibility by holding focus groups, constructing surveys and conducting analyses of the market. At the surface, this may seem completely fine; many businesses frequently do this. But consider the CEO’s preconceived beliefs about the product that it will be very successful, and how these beliefs may influence her team’s research experience. The marketing team’s research is done with the knowledge of their boss’s expectations, which may lead them to form hypotheses based on those expectations, thereby confirming those views. In the end, this biased process may result in the product’s failure, as no real research is invested into its design or market potential, ultimately costing the business a lot of money.3


The accuracy of first impressions is a matter of debate. Nobel prize winning psychologist and author of Thinking, Fast and Slow, Daniel Kahneman is of the mind that first impressions are indeed accurate to a degree. Kahneman argues that you can very quickly judge whether you will like a person, or if others will. He does add in a caveat, however: first impressions are not perfect, and correcting them is very challenging, as we often fall prey to the halo effect and/or confirmation bias.1

In contrast, Alexander Todorox, a researcher at Princeton University and author of Face Value, states that first impressions are predominantly inaccurate. Todorov argues that, although theories of physiognomy – the study of inferring personality characteristics from subtle facial characteristics- are fundamentally wrong, they still contain some truth. He specifically writes that “we immediately form impressions from appearance, we agree on these impressions, and we act on them.” In other words, once we form a first impression of someone, we tend to stick with it and treat it as fact. This is why people who “look” more competent, such as if they wear glasses, are more likely to be hired in leadership positions. The issue however, is that these judgments are completely subjective; which facial cues translate into competency to one person may not be true for another person. This subjective notion of what “looks” like a leader can also have dangerous effects when it comes to equating leadership with familiarity, therefore inhibiting diversity and progress.

Learn more: One Unconscious Bias is Keeping Women Out of Senior Roles

Moreover, what we perceive to be characteristics of a competent person do not necessarily translate into actual characteristics. Faces are not static; they are dynamic. Although a smiling person is frequently rated as more trustworthy, there is no link between smiling and trustworthiness – even if there was one, smiles fade.12

Case Studies

User experience and visual appeal 

A 2006 paper by Lindgaard and colleagues explored whether a first impression can be formed via brief exposure to a website. Participants viewed website homepages for 50 milliseconds each, then rated the visual appeal of each page. Lindgaard and colleagues found that participants reliably decided which homepages they liked and which they did not like within 50 milliseconds. They suggest that this indicates that impressions of websites are largely impacted by the visual appeal of closely related to design layout and colour choices. These findings build upon previous studies which examined how usability of a webpage affects user experience and found that visual appeal of the site actually drew attention away from usability issues.10 More research needs to be conducted to examine how long these first impressions last, but web designers should consider visual appeal to be as important as usability when designing websites.11

Biased medical diagnoses

First impressions are known to influence judgments and decisions more than information learned later on Kostopoula and colleagues (2016) examined whether physicians are prone to first impression bias, and whether it affects diagnoses. The recruited physicians saw six patient cases, three of which could have been cancer. Each cancer included two consultations. After reading the patient description and presenting problem, physicians could request more information about the patient. The authors measured the association of the first impressions with the final diagnoses decisions. Kostopoula and colleagues found that there was indeed a strong association between the initial diagnoses by the physician and subsequent diagnoses. Therefore, the physicians were likely basing their final diagnoses largely on the first pieces of information they learned about the patients and may have sought out information to support those original hunches (thus using the confirmation bias). This finding can be problematic, especially if the physician’s initial impression is an absence of cancer. When patients present subtle or unconvincing symptoms, physicians may not be sold enough information early on to consider seriously following up, potentially causing diagnostic delays and further health complications in patients.8

Related TDL Content

The halo effect, explained.

If you are interested in learning more about related biases, this article outlines the halo effect: how positive impressions of people in one area can influence our expectations and feelings towards them in unrelated aspects of their lives.

Primacy effect, explained.

If you are interested in reading more about how the order of information we perceive matters, this article outlines the primacy effect: how we often remember the first details we encounter best.

Anchoring bias, explained.

If you are interested in learning more about the implications of relying heavily on initial information, this article describes the anchoring effect and how it is manipulated in the courtroom.


  1. Can we trust first impressions?(2019, November 7). Psychologies.
  2. Confirmation bias definition. (n.d.). Investopedia.
  3. Confirmation bias: How it affects your organization | HBS online. (2016, August 18). Business Insights
  4. Fang, X., Rajkumar, T. M., Sena, M., & Holsapple, C. (2020). National culture, online medium type, and first impression bias. Journal of Organizational Computing and Electronic Commerce,30(1), 51-66.
  5. Halo effect – Biases & heuristics | The decision lab. (2020, August 24). The Decision Lab.
  6. Hatcher, R. (n.d.). The “Halo effect” and how it influences your hiring decisions. MAU | Staffing and Recruiting.
  7. Hirshleifer, D., Lourie, B., Ruchti, T. G., & Truong, P. (2020). First impression bias: Evidence from analyst forecasts*. Review of Finance
  8. Kostopoulou, O., Sirota, M., Round, T., Samaranayaka, S., & Delaney, B. C. (2016). The role of physicians’ first impressions in the diagnosis of possible cancers without alarm symptoms. Medical Decision Making37(1), 9-16.×16644563
  9. Lim, K. H., Benbasat, I., & Ward, L. M. (2000). The role of multimedia in changing first impression bias. Information Systems Research11(2), 115-136.
  10. Lindgaard, G., & Dudek, C. (2002). User satisfaction, aesthetics and usability. IFIP Advances in Information and Communication Technology, 231-246.
  11. Lindgaard, G., Fernandes, G., Dudek, C., & Brown, J. (2006). Attention web designers: You have 50 milliseconds to make a good first impression! Behaviour & Information Technology25(2), 115-126.
  12. The psychology of first impressions: Are they accurate?(2020, August 9). Ray Williams.

About the Authors

Dan Pilat's portrait

Dan Pilat

Dan is a Co-Founder and Managing Director at The Decision Lab. He is a bestselling author of Intention - a book he wrote with Wiley on the mindful application of behavioral science in organizations. Dan has a background in organizational decision making, with a BComm in Decision & Information Systems from McGill University. He has worked on enterprise-level behavioral architecture at TD Securities and BMO Capital Markets, where he advised management on the implementation of systems processing billions of dollars per week. Driven by an appetite for the latest in technology, Dan created a course on business intelligence and lectured at McGill University, and has applied behavioral science to topics such as augmented and virtual reality.

Sekoul Krastev's portrait

Dr. Sekoul Krastev

Sekoul is a Co-Founder and Managing Director at The Decision Lab. He is a bestselling author of Intention - a book he wrote with Wiley on the mindful application of behavioral science in organizations. A decision scientist with a PhD in Decision Neuroscience from McGill University, Sekoul's work has been featured in peer-reviewed journals and has been presented at conferences around the world. Sekoul previously advised management on innovation and engagement strategy at The Boston Consulting Group as well as on online media strategy at Google. He has a deep interest in the applications of behavioral science to new technology and has published on these topics in places such as the Huffington Post and Strategy & Business.

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