How Guessing Works

By: Alia Hoyt
Can you guess how many candies are in each jar? Chefshots - Eric Futran/Getty Images

Life is sort of like one big guessing game. All day long, we venture guesses about everything from the mundane, like calling heads or tails on a coin toss, to guessing someone's height to more nuanced speculations, such as a person's true intentions. Much as we hate to admit it, humans don't actually know everything, especially when multiple variables are involved. That's when the act of guessing comes into play.

"Before books, before libraries, before Google, guessing was the only way humans navigated in the world," explains David Ezell, CEO and clinical director of counseling and mental wellness group, Darien Wellness in Darien, Connecticut. (As a cognitive behavioral therapist, he says he talks to people all day long about how they guess and how those guesses affect them). "Throughout the days, thousands of decisions had to be made with little or no facts. So, guessing was the way humans decided to eat a red berry (or not), or go down the left path instead of the right."


The exact mechanisms behind how our brains land on one guess or another are not technically known yet. "There isn't really the neuroscience to say this pathway or that. The brain is very interconnected and this is sort of a global process," says Dr. Gail Saltz, psychiatrist and the author of "The Power of Different: The Link Between Disorder and Genius.'"

Certain types of guesses do benefit from specific areas of the brain, even though they're probably not the only parts involved. "The cerebral cortex or cerebellum has been demonstrated to be involved in hunches. Neuroscientists have long known that guessing generally involves the activation of regions distributed throughout the brain," says Dr. Ben Michaelis, clinical psychologist and creator of the One Minute Diagnosis website in an email interview. "When you are guessing about visual subjects your frontal lobe and occipital lobe are activated. When you are guessing about numerical quantities the superior parietal lobe has been shown to be activated."

This isn't terribly surprising, as the parietal lobe is associated with a lot of capabilities that influence guessing, such as spatial position, object identification and body navigation. The frontal lobe is responsible for personality, sense of smell and movement, and the occipital lobe handles vision. The temporal lobe can affect guessing success, since it's in charge of memory, as well as speech [source: Johns Hopkins Medicine].


Factors That Affect Guessing Accuracy

The principal lobes of the brain are the frontal (yellow), temporal (green), parietal (pink) and occipital (red) lobes. The cerebellum (purple) controls muscle coordination, balance and posture. Science Photo Library/Getty Images

Clearly, guessing is not static across the board. There are many types of guessing, including:

Wild guesses – Occasionally we do throw caution by the wayside and venture a guess off the top of our heads, with zero outside information or input (hopefully, not about something too important).


Educated guesses – This is the "middle ground" of guessing, in which people tend to choose a ballpark figure based on having some information (as opposed to picking a number at random).

Estimating – People have information that is going to inform their answers, such as knowledge about the likely distance, volume or past behavior that are valuable tools in determining the guess.

Intuition is not exactly a form of guessing, but it does play a role, even if you're not aware that you have the information squirreled away in your brain. "From a brain or neurologic perspective there can be implicit or unconscious recall in the memory that is not in your awareness, but is informing your guess," Saltz says of intuition. "Most guesses are leaning toward something because of implicit memories and unconscious information."

A large part of that is knowing what affects our guesses in the first place. "The problem sometimes with guessing is that one can conjure up a memory that may not be accurate, but may feel really accurate," Saltz says.

Incorrect memories aren't the only things keeping us from venturing accurate guesses. Emotional state and ties can also get in the way. Saltz explains that people with high anxiety or who are risk averse tend to have trouble with accurate guesses of others' emotions. Also, if you have a significant emotional connection to one potential answer, it's the one most likely to "pop out," making you think it's the correct answer, when in fact, the emotional tie is coloring your view.

Certain people also inherently have skill sets that make them better at some kinds of guesses. Consider a scenario when you're trying to guess the number of jelly beans in a jar at a county fair. People with superior math and spatial relation abilities will likely come closer to the correct answer than people with other strengths.

While you probably won't ever learn to guess with 100 percent accuracy, there are ways to fine-tune the skill.


Getting Better at Guessing

Britain's Prince William reacts as he plays a guessing game with 22-year-old Sherihan Sharis, during his visit to a Centrepoint hostel in London on Jan. 10, 2017. Centrepoint is a charity for homeless youth. EDDIE MULHOLLAND/AFP/Getty Images

Remember that "guess the jelly beans in the jar" scenario? Just because you were off by a couple hundred or so doesn't mean that all hope is lost. It's entirely possible to improve guessing abilities, both as it relates to concrete examples like the jelly bean jar, or by accurately surmising other people's intentions/opinions. How? "If you can practice a specific type of guessing and get feedback about your guesses ... your guesses will become more accurate over time," says Michaelis.

There are some steps to take when engaging in an items-in-the-jar contest that can narrow your guessing field. Clark University researchers in Massachusetts found that spherical objects, when put in a container randomly (as opposed to careful packing) occupy about 64 percent of said container [source: Baker and Kudrolli]. Non-spherical objects, like cubes or "peanuts," take up somewhere between 50 and 54 percent of the space. Jelly beans were not studied, but they aren't likely to be any better than the other nonspherical objects because their uneven shapes don't allow them to settle as efficiently as those with evenly distributed sides [source: Schewe].


That's all fine and dandy, but how's a regular person to parlay that into an accurate guess? "First, estimate the size of the jar," says New York University researcher and physics expert Jasna Brujic in a Scientific American interview. "Then look to see if all the candies are the same size. If they are, take 64 percent of that volume and divide it by the size of the candy to get the total number that would randomly fit inside. If they aren't equally sized, divide a slightly larger area, around 70 percent, by the average size of the candies."

So, grab a calculator, a few jars of differing sizes and a couple packs of leftover jelly beans. The formula sounds complex, but will probably be easier to figure after a couple of practice rounds.


Overcoming Cognitive Distortions

Sometimes it can be hard to guess what another person is thinking. DMH Images/Getty Images

Another area where people often guess incorrectly is in reading other people's emotions (or their own). This is called cognitive distortion, inaccurate thoughts that often encourage negative thinking. Unfortunately, we all fall victim to thinking errors to a degree. Two examples are polarized thinking (everything is either "wonderful" or "terrible") and jumping to conclusions [source: Grohol]. To illustrate, therapist Ezell offers the following example of how thinking errors affect guessing: A boy walks into a room, sees a girl and reads the expression on her face as "she doesn't like me."

"The primary cognitive distortions involved here are polarized thinking, overgeneralization and jumping to conclusions," Ezell says. "Polarized thinking has him assuming she has an opinion — how does he know she even had a feeling one way or the other? Overgeneralization has him thinking girls have negative reactions — possibly based on history, but also driven by self-esteem issues. Jumping to conclusions, or mind reading — we never know what anyone is really thinking. We can guess but we will never know."


So, the boy's guess that the girl doesn't like him is entirely based on inaccurate assumptions and intuition. "Catching these automatic thoughts —what we have been calling guesses — and running them through an evidence-based process — will help us understand other people and in turn, ourselves," Ezell says.

The process has a lot to do with resisting snap judgements, evaluating real information and taking a more positive approach. For example, human instinct is to assume that someone doesn't like us if they cast a less-than-friendly look in our direction, when in fact it could have been completely unintentional, and merely the result of a difficult day or other encounter.

"Jumping to conclusions is defined as making interpretations without actual evidence," explains licensed mental health counselor Donna White in a blog for Psych Central. "If you find yourself engaging in this type of thinking, take a step back and ask yourself 'do I really know this to be true?' If the answer is 'no', then focus on the things that you know to be true."

Although it might seem inconsequential to get the wrong idea about a mere glance or other misguided guess, it can actually have lasting repercussions. "The problem with guesses is that our brain doesn't remember it's a guess. We accept our guesses as facts," Ezell says. "If we could maintain that memory of that thought not being totally accurate we would be in a much better space. But that is what people who are self-aware do. They know when things are true, they know when things are hypotheses and they know when things are purely a guess."


Lots More Information

Author's Note: How Guessing Works

We make dozens of guesses every day, whether we realize it or not. Although I don't have much interest in mastering the beans-in-a-jar type of guessing, I find the concept of overcoming cognitive distortions to be intriguing, potentially beneficial and just plain smart.

Related Articles

More Great Links

  • Baker, Jessica and Arshad Kudrolli. "Maximum and minimum stable random packings of Platonic solids." Physical Review. Dec. 15, 2010 (April 14, 2017)
  • Bode, S.; C. Bogler, CS Soon and JD Haynes. "The neural encoding of guesses in the human brain." Neuroimage. Jan. 16, 2012 (May 8, 2017)
  • Ezell, David. CEO and Clinical Director of Darien Wellness. Email interview April 10, 2017.
  • Grohol, John M. "15 Common Cognitive Distortions." Psych Central. 2016 (April 14, 2017)
  • Johns Hopkins Medicine. "Inside the Brain." 2017 (May 8, 2017)
  • Jolly, Stephanie. "Should You Guess on the PSAT, SAT or ACT?" Kaplan Test Prep. Sept. 22, 2016 (April 14, 2017)
  • Michaelis, Ben. Clinical Psychologist and Creator of Email interview April 12, 2017.
  • Peeples, Lynne. "Researchers have developed a new model that can estimate the number of objects randomly packed together." Scientific American. Aug. 4, 2009 (April 14, 2017)
  • Saltz, Gail. psychiatrist and the author of The Power of Different. Telephone interview April 12, 2017.
  • Schewe, Phillip F. "Packing it all in for the holidays: Scientists see how many polyhedrons can fit into a box." Dec. 20, 2010 (April 14, 2017)
  • Today I Found Out. "THE ORIGIN OF THE EXPRESSION "GUESS WHAT? CHICKEN BUTT!" July 6, 2016 (April 14, 2017)
  • White, Donna M. "Challenging Our Cognitive Distortions and Creating Positive Outlooks." Psych Central. 2016 (April 14, 2017)