Contrast Effect: Judging Things by What Came Before

The Contrast Effect describes how our judgments of people, objects, or experiences are heavily influenced by what we have just seen or experienced. Instead of evaluating something in absolute terms, we unconsciously compare it to recent reference points. As a result, the very same candidate, product, or experience can feel great, mediocre, or terrible depending on what came immediately before it.

Imagine tasting a moderately sweet dessert. If you just ate something extremely sugary, the dessert may taste bland. If you just had something plain or bitter, it may taste deliciously sweet. Objectively, the dessert hasn’t changed—only the context has. The contrast effect shows up in hiring decisions, product evaluations, test scores, dating, and everyday impressions.

This bias demonstrates that our perception is relative, not absolute. The brain is wired to detect differences and changes rather than fixed levels. While contrast can be useful for highlighting boundaries, it also creates systematic distortions when we assume we are judging things on their own merits.

The Psychology Behind It

The contrast effect arises from several intertwined psychological processes:

1. Relative Encoding in Perception
   Our sensory systems are tuned to changes and differences, not stable baselines. Neurons adapt to recent stimulation, so a moderate stimulus can feel weak after a strong one and strong after a weak one. This neural adaptation underlies contrast effects in brightness, weight, taste, and other sensory domains.

2. Anchoring on Recent Examples
   When making judgments about quality or value, we implicitly anchor on the most recent case we evaluated. A job candidate may look stronger after a weaker one and weaker after a stellar one. We compare "better or worse than the last" instead of asking whether they meet an objective standard.

3. Category Boundaries and Scales
   We often lack absolute scales for constructs like "attractive," "expensive," or "difficult." Instead, we construct these scales on the fly using available examples. Extreme cases stretch or compress the scale, making moderate cases look relatively better or worse.

4. Effort Savings in System 1
   System 1, our fast and intuitive mode of thinking, favors efficient shortcuts. Comparing a new stimulus to a recent one is easier than computing absolute judgments from scratch. Unfortunately, this convenience can bias decisions in subtle but consequential ways.

5. Contextual Framing by Choice Architects
   Marketers and negotiators deliberately exploit contrast by placing target options next to more extreme comparators (very high-priced items, very low-quality options) to make the target look more appealing.

Together, these processes create a world where "how good" or "how bad" something seems depends strongly on what else is around it, in time or space.

Real-World Examples

1. Hiring and Admissions Decisions

Interviewers who see a series of weak candidates may rate a merely average candidate as outstanding by contrast. Conversely, after interviewing several exceptional applicants, a solid candidate may appear underwhelming. Similar patterns occur in university admissions when evaluators review batches of applications.

2. Price Comparisons in Retail

Stores often place an extremely expensive item next to a high-priced but slightly cheaper "target" item. The target then appears reasonable by comparison. For instance, a $1,500 watch might be displayed next to a $7,000 watch to make the first seem like a fair deal, even if it is overpriced in absolute terms.

3. Performance Reviews

Managers who review a very high-performing employee just before a mid-level performer might downgrade the latter’s evaluation, perceiving them as weaker than they would have if judged in isolation. Conversely, following a poor performer, a mid-level employee may seem exceptional.

4. Physical Appearance and Dating Apps

On dating platforms, judgments of attractiveness can shift dramatically depending on who appears in the feed beforehand. After viewing a series of strikingly attractive profiles, a typical profile may be rated lower than it would have been if seen first or in a more average sequence.

5. Customer Experience and Service Recovery

If a customer has just endured a very negative experience, a merely decent follow-up interaction can feel surprisingly positive by contrast. Conversely, after a stellar experience, an average one may feel disappointing.

Consequences

The contrast effect can shape outcomes across domains:

• Unfair Evaluations
  Candidates, students, employees, or proposals can be judged more harshly or more favorably based on the order of presentation rather than true merit.

• Manipulated Preferences
  Marketers and negotiators can steer choices by presenting extreme comparators that distort perception of what is reasonable.

• Inconsistent Standards
  Organizations may believe they are applying objective criteria, but in practice, standards shift depending on what evaluators have just seen.

• Misallocation of Resources
  Jobs, funding, or opportunities may go to those who benefited from favorable contrast rather than those best suited.

Understanding the contrast effect is crucial for designing fairer evaluation systems and more transparent choice environments.

How to Mitigate It

The goal is not to eliminate comparisons—they are often useful—but to prevent them from silently distorting important judgments.

1. Use Clear, Absolute Criteria
   Define evaluation rubrics before reviewing options: specific skills, behaviors, or metrics. Score each case against these criteria rather than relative to the last example.

2. Randomize or Balance Order
   In hiring, admissions, or grading, randomize the order of items or interleave strong and weak candidates intentionally to reduce systematic order effects.

3. Blind or Pooled Evaluation
   Evaluate items in pooled formats (e.g., reviewing written statements without seeing previous scores) or in parallel comparisons that explicitly show all options at once rather than sequentially.

4. Awareness and Debriefing
   Train evaluators about the contrast effect and encourage them to check when they feel particularly impressed or disappointed: "Is this judgment driven by the last candidate, or by objective performance?"

5. Structured Pricing and Menus
   For consumers, be wary of "decoy" or "extreme" options whose primary role is to make another option look attractive. Compare offers using external benchmarks rather than just local context.

6. Pause Between Evaluations
   In important decisions, introduce short breaks or segmentation to reset reference points rather than judging long sequences back-to-back.

Conclusion

The contrast effect shows that our judgments are deeply contextual. We rarely evaluate people or options in a vacuum; instead, we rely on recent comparisons, which can lead to biased decisions and inconsistent standards. Recognizing this bias helps us design fairer processes—in hiring, admissions, pricing, and everyday choices—and reminds us to look beyond "what came just before" when deciding what is truly good, fair, or valuable.