What is anecdotal evidence?

Anecdotal evidence is storytelling. It relies on human beings’ love for telling stories, and then using those tales to shape our beliefs. From this perspective, anecdotal evidence should actually be considered the norm.

Research has shown that thinking anecdotally comes naturally, whereas thinking scientifically is a more difficult and nuanced skill to grasp. This is why superstition and belief in magic has lasted for as long as humankind has been around, while science is only a few 100 years old. It took many years before humans started considering factors such as variables and biases.

People remember – and tell – dramatic and extraordinary stories. Stories are sexy! They have dramatic arcs and anticipated climaxes and events. Things happen, and you can point to those things right away. Data and numbers and sample size seem comparatively boring, and are therefore not as likely to stick in the minds and memories of people.

A single death is a tragedy; a million deaths is a statistic.

– Joseph Stalin

That horrific quote was used by Joseph Stalin to justify his leading the Soviet Union into World War II. While we obviously don’t agree with his quote, his point is that a single death is treated as powerful anecdotal evidence, but once that sample size increases by that scale, the impact of individual events diminishes greatly.

Let’s take a look at some of the apples-to-apples differences between anecdotal evidence and statistics:

Examples of when Anecdotal Evidence is Dangerous

While it is human nature to remember stories and have them shape our beliefs, anecdotal evidence becomes dangerous when flat-out wrong situations or outcomes are “justified” based upon the observation of said anecdotal evidence. Let’s look at three examples from very different arenas:

• Vaccinations – There has been a recent groundswell linking vaccinations in children to autism, partly caused by the activism of celebrities like Jenny McCarthy. Yet, research has proven that the chemical ethylmercury (from the vaccine) is expelled from the body well before it can cause any damage. But because of several high-profile cases involving vaccines and autism – coupled with our cognitive tendency to pay attention to false positive anecdotes – a dangerous line of thinking has evolved. Increasing numbers of parents are not vaccinating their infants, leaving them susceptible to infectious diseases.

• Weight loss supplements – Similarly, all it takes is one (or a few) high profile cases, and people will throw all logic to the wind. You’ve seen commercials for supplements that promote weight loss, accompanied by brief anecdotes (and before-and-after photos) of people who’ve experienced this weight-loss success. Interested viewers will remember the success of those nice, skinny people they saw on screen. They won’t even consider the millions of cases where these weight loss supplements might not have worked at all.

• Peyton Manning struggles in cold weather – There is a commonly held belief in sports that Peyton Manning, one of the all-time great quarterbacks, can’t play in cold weather situations. According to a Denver Broncos blog, Manning’s career QB rating is at 96.9, while his QB rating in cold games (below 40 degrees) is at 86.2. Pretty simple correlation right?

  Well, not so fast. Consider that 19 of his 23 “cold” games were played on the road, where teams and players (including Manning) historically fare worse. This is the type of variable that most fans fail to consider, leaving them with tenuous links between Manning’s slumping statistics in the cold and an overriding theory that Manning just can’t play in those conditions. But really, statistics aside, why do people think Manning isn’t a good cold-weather quarterback?

  Because of how he and his team were knocked out of the playoffs in 2002, 2003 and 2004, according to The Minitab Blog:

• 2002: Lost to the Jets 41-0, temperature was 34 degrees.

• 2003: Lost to the Patriots 24-14, temperature was 31 degrees.

• 2004: Lost to the Patriots 20-3, temperature was 27 degrees.

Three high-profile losses under the bright spotlight of the NFL Playoffs early in his career? Those resonating anecdotes shaped a narrative that would dog him for the rest of his career: Peyton Manning can’t play in cold weather.

What does this have to do with sales management?

We’re glad you asked! The reason this is an important consideration for sales managers is that making business, management and operational decisions based on anecdotal evidence can lead you on a slippery slope down a wrong rabbit hole. One decision erroneously made – based upon anecdotal evidence – can spawn a slew of similarly bad decisions.

A salient example is in sales coaching. A sales manager might observe, from a distance, that a rep isn’t gaining traction on his calls, and often finds himself getting hung up on. The manager might then enroll that rep in an intensive program to work on his skills in building engagement on the call, speaking to decision-makers and overcoming objections.

But what if the anecdotal evidence that the manager is relying on occurred during a bad day for the rep? What if the rep’s sales metrics reveal that he typically crushes calls, with the longest talk times and the most meetings scheduled? By solely relying on that anecdotal evidence – and not diving into the relevant sales metrics – that sales manager is crafting a sales coaching plan that is a poor fit, and a waste of time, for that sales rep.

We hope you’ve realized just how dangerous relying on anecdotal evidence in lieu of statistically supported data and sales metrics can be. Don’t make these mistakes! Shift your thinking from cherry-picking memorable anecdotal evidence to demanding a comprehensive and considerate study of data, with proper sample sizes and controlled variables.