The simple way to make your marketing claims 42.9% more believable

A few weeks back, I stumbled across a Reddit post that talked about the first measurement ever taken of Mount Everest. Rather than listing the exact measurement of 29,000 feet, the British Royal Geographical Society declared Mount Everest’s elevation to be 29,002 feet. It’s one of those facts that seems fake, but there’s good evidence that it’s true.

Clearly, the surveyors thought that rounded numbers seemed less believable. They thought that 29,000 feet sounded too vague to be accurate. Turns out, this is something that numerous studies have since proven.

Source

Can you spare 17 cents?

In a 1994 study published in the Journal of Applied Social Psychology , University of California, Santa Cruz researchers Michael D. Santos, Craig Leve, and Anthony R. Pratkanis looked to test the pique technique, which suggests that people are more likely to agree or comply with an ask if “mindless refusal” is disrupted by a strange or unusual request. They asked three female actors to approach 289 adults over several days.

Each actor was instructed to ask the passersby for change. But there was a twist. Half were asked: "Can you spare 17¢ (or 37¢)?" The other half were asked: "Can you spare a quarter (or any change)?"

What they found was that asking people to spare a specific amount made them more likely to donate change than the general request. Nineteen years later, five different researchers tested the same theory again.

Can you spare 37 seconds?

The 1994 study proved specific numbers worked with money, but would it work with time? In 2015, Nicolas Guéguen, a professor of behavioral sciences at the University of Southern Brittany in France, reexamined the pique technique with a different type of request.

For this experiment, the researchers recruited four female actors, dressed identically in black, to ask passersby to complete a survey. Three hundred passersby were asked in total (150 men and 150 women).

However, 150 were asked: “I wonder if you have a little time to spare to answer a survey.” The other 150 were asked: “I wonder if you have 37 seconds to spare to answer a survey.”

Of the 150 people asked to spare a little time, only 63 agreed. Of the 150 people asked to spare 37 seconds, 90 agreed. A specific request boosted compliance by 42.9%.

What’s happening here? Well, we have a natural tendency to assume that rounded numbers are made-up. The lack of precision leads us to assume the number is less reliable.

This won’t just affect donation requests and survey attempts. The same effect is visible in four-figure negotiations.

Would you take $2,135?

In 2013, four researchers published a paper in the Journal of Experimental Social Psychology on precise offers.

Hundreds of participants in one of the studies summarized were asked to negotiate the hypothetical sale of a second-hand car. Half of the buyers were told to start the sale with a rounded price of $2,000. The other half were told to use a precise price point of either $1,865 or $2,135.

The researchers wanted to see if more specific starting prices would affect the amount that sellers tried to haggle.

Turns out, when buyers open with a precise asking price ($1,865 or $2,135), sellers countered with smaller adjustments versus when given a rounded price ($2,000). Using precise numbers made car prices seem more justified, leading to higher final selling prices.

Rounded numbers seem less believable. Specific numbers appear trustworthy. So, when someone asks for 17 cents, we think they must have a good reason. When someone asks for 37 seconds, we think, “This really won’t take long.” And when Everest is measured at 29,002, we think that must be right!

I spoke with the godfather of influence, Robert Cialdini, about the precise number effect on Nudge, listen to the discussion here.

We believe precise numbers.

Marketers may round numbers to sound cleaner and more polished. But, precision is what actually earns trust. Specific numbers tell customers that a claim came from somewhere real. Someone took the time to measure, so we should trust the results.

So, lean into precise numbers. If Mount Everest is 29,002 feet tall, use the two feet.