How Guinness made their pint seem 'perfect' | Nudge Newsletter


Specific Number Bias

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Which coaster makes Guinness seem like the โ€˜๐˜ฑ๐˜ฆ๐˜ณ๐˜ง๐˜ฆ๐˜ค๐˜ต ๐˜ฑ๐˜ช๐˜ฏ๐˜ตโ€™?

Thatโ€™s what Schindlerยน (Rutgers University) and Yalch (University of Washington) studied in 2006.

They showed participants ads that used specific numbers, for example:

  • โ€œIt takes 119.5 seconds to pour the perfect pint.โ€

Vs. rounded numbers:

  • โ€œIt takes 2 minutes to pour the perfect pint.โ€

Turns out, claims made using ๐ฌ๐ฉ๐ž๐œ๐ข๐Ÿ๐ข๐œ ๐ง๐ฎ๐ฆ๐›๐ž๐ซ๐ฌ are perceived to be 10% ๐ฆ๐จ๐ซ๐ž ๐›๐ž๐ฅ๐ข๐ž๐ฏ๐š๐›๐ฅ๐ž.

By pointing out that it takes exactly 119.5 seconds to pour, Guinness makes their โ€œPerfect Pintโ€ claim more believable

Guinness are hardly the first to try this; dozens of companies use specificity in their claims. ๐Ÿ‘‡

Heinz stated they make 57 varieties of sauce.

Burger King has been grilling since 1964.

WD-40 is named as such because it's the 40th iteration of the product.

Dyson created 5,127 prototypes before mastering the vacuum.

But my favourite example of specificity in marketing is this from Itsu.

All these companies know that specificity boosts trust.

Perhaps thatโ€™s one reason why Guinness is now Britainโ€™s favourite pint.


Last week I shared how I used Descript to edit the pod.

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In the past, I used Mailchimp. It was fineโ€ฆ but a bit clunky.

About 728 days ago*, I switched to Kit.

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Hope you're all well! I'm working hard on something exciting. โ€” Phill โ€‹

ยนSchindler, R. M., & Yalch, R. F. (2006). It seems factual, but is it? Effects of using sharp versus round numbers in advertising claims. Advances in Consumer Research, 33, 586โ€“590.

*Yes, that is a blatant use of the specific number bias

As a behavioural science practitioner, I believe in the peak-end rule.

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