Scarcity, Anchoring, and the Decoy Effect
Beyond emotions, persuaders use cognitive biases — quirks in how your brain processes information. These biases are hardwired. You can't eliminate them, but you can learn to recognise when they're being exploited.
The Top Five Cognitive Biases Used Against You
1. Scarcity Bias
"Only 3 left!" "Offer ends tonight!" "Limited edition!" Your brain assigns more value to scarce things. If something might run out, System 1 screams "GET IT NOW!" This is why Booking.com shows "5 people looking at this room" and airlines show "only 2 seats left at this price."
Reality check: the scarcity is often manufactured. The "limited edition" might have 10 million units.
2. Anchoring
The first number you see becomes your reference point. "Was $200, now $99!" — the $200 is the anchor. It makes $99 feel like a bargain, even if the product was never worth $200.
Retailers know this. High "original" prices exist solely to make the "sale" price look good. The ACCC has taken action against retailers for fake original pricing.
3. The Decoy Effect
Three options: Small coffee $3, Medium $6.50, Large $7. The medium exists only to make the large look like amazing value. Without the medium, you'd compare $3 and $7 and might choose the $3. With the decoy, you feel clever choosing the $7.
This is used in subscription pricing, movie tickets, and restaurant menus worldwide.
4. The Bandwagon Effect
"Australia's #1!" "Used by millions!" "Trending now!" If everyone else is doing it, your brain assumes it must be good. This was useful when our ancestors needed to follow the group to survive. Now it's used to sell you things.
5. Loss Aversion
"Don't miss out!" "You'll regret not acting!" Kahneman proved that humans feel the pain of losing something roughly twice as strongly as the pleasure of gaining the same thing. Marketers exploit this by framing everything as a potential loss.
Tonight's Question
"Have you ever bought something because it was 'on sale' and then realised you didn't really need it? What bias was at work?"
Bias Hunters
- Visit an online store (Amazon, any major retailer).
- Find examples of each of the five biases being used.
- Screenshot or note each one.
- Award points: 1 point per bias found. 5 bonus points for finding all five on a single page.
- Discuss: which bias do you find hardest to resist personally?
Go Further
- Book: Predictably Irrational by Dan Ariely (2008) — entertaining experiments showing how biases affect decisions.
- Research: How do real estate agents use anchoring? (Hint: the asking price.)
- Experiment: Ask friends: "Is the population of Australia more or less than 50 million?" Then ask: "What is it?" Compare to asking without the anchor. Watch anchoring in action.
- Question: If these biases are hardwired, can we ever truly make "rational" decisions?
What We Simplified
- Biases have useful functions. Scarcity bias helps us prioritise genuinely rare resources. Bandwagon effects help groups coordinate. They're not purely negative.
- Awareness helps but doesn't eliminate biases. Even people who study biases professionally still fall for them.
- Some "sales" are genuine. End-of-season clearances, for example, reflect real price reductions as stores make room for new stock.
Sources
- Ariely, D. (2008). Predictably Irrational. HarperCollins.
- Kahneman, D. & Tversky, A. (1979). "Prospect Theory: An Analysis of Decision under Risk." Econometrica, 47(2), 263-292.
- Huber, J., Payne, J.W. & Puto, C. (1982). "Adding Asymmetrically Dominated Alternatives: Violations of Regularity and the Similarity Hypothesis." Journal of Consumer Research, 9(1), 90-98.
- ACCC (2023). "Misleading Pricing Practices." ACCC
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