Sure, we all know that an Ivy League education, a stint at a blue-chip firm, and stellar sales skills can help us get ahead. But it may surprise you just how many other, seemingly random variables can contribute to your professional success.
From the month you were born to your comedic timing, the weirdest quirks can affect how successful you'll ultimately be.
We combed through research on success to identify 26 surprising things that can influence your career trajectory. While some factors can be sought out, others are beyond your control.
Defiant, rule-breaking kids often grow up to earn higher salaries
In 1968, nearly 3,000 sixth-graders living in Luxembourg took intelligence tests and answered questions about their feelings toward school. Their teachers also filled out questionnaires about the students' behavior. At the time, researchers assessed the students' family background as well.
In 2008, researchers revisited this data in order to see which childhood traits predicted career success and income. They were able to get in touch with 745 of the students, who were now about 52 years old. Perhaps unsurprisingly, more studious kids (as rated by teachers and by the kids themselves) went on to land better jobs.
But the researchers were surprised to find one childhood characteristic — beyond IQ, parents' socioeconomic status, and the amount of education the students attained — that predicted higher adult income: rule-breaking and defiance of parental authority.
Parents' high expectations for their kids tend to matter more than income or assets for their child's success
Using data from a national survey of 6,600 children born in 2001, University of California at Los Angeles professor Neal Halfon and his colleagues discovered that the expectations parents hold for their kids have a huge effect on attainment.
"Parents who saw college in their child's future seemed to manage their child toward that goal irrespective of their income and other assets," he said in a statement.
The finding came out in standardized tests: 57% of the kids who did the worst were expected to attend college by their parents, while 96% of the kids who did the best were expected to go to college.
That parents should keep their expectations high falls in line with another psych finding — the Pygmalion effect, which states "that what one person expects of another can come to serve as a self-fulfilling prophecy" — as well as what some teachers told Business Insider was most important for a child's success.
Being married is linked to higher salaries for men and lower salaries for women
A recent study finds that men experience a "marriage premium": Their salaries generally go up when they get hitched. Women, on the other hand, tend to see their salaries go down when they tie the knot.
Specifically, married men between 28 and 30 years old earn about $15,900 more per year in individual income compared to their single counterparts, while married men between 44 and 46 years old make $18,800 more.
And although these findings were not statistically significant, married women between 28 and 30 years old earn $1,349 less per year in individual income than their single counterparts, while married women between 44 and 46 years old earn $1,465 less.
Your birth month may be important in determining success
Many studies look at what's variously called the "relative-age effect," "month of birth bias," or "birth-date effect."
The basic principle is that kids born right before an annual cutoff date for starting school or sports are at a disadvantage because they're essentially a full year younger than other members of the group. That can make a big difference in some children's physical, emotional, and intellectual maturity. On the other hand, just missing the date tends to mean you'll be more developed than your peers.
Malcolm Gladwell popularized this idea in the book "Outliers," which explored how more professional hockey players from Canada were born in January, February, and March than any other months. The reason? Canada's cutoff date for hockey programs is Jan. 1.
Similar research has shown that the number of CEOs with June and July birthdays is far below the expected normal distribution. That's because kids born in June and July are usually the youngest in school, potentially putting them at an early intellectual disadvantage.
Your birth order can also influence your personality and development ...
Research suggests that first-borns tend to be highly ambitious and competitive and excel academically.
According to a 2013 study, it's thanks to their parents, who give them their best parenting but ease up on kids born later. As Derek Thompson points out at The Atlantic, international surveys of birth orders and behavior suggest that first borns tend to have higher IQs and perform better in school across the globe. "Looking at parent evaluations of children from the National Longitudinal Survey of Youth in 1979, the researchers found that mothers are much more likely to see their first children as high-achievers. They regard their subsequent children as considerably more average in their class."
By contrast, the youngest siblings are often the most creative and entertaining in their families, which in some kids can help them end up in creative roles or mid-level management.
Finally, studies suggest that only children tend to be more self-centered and success-seeking, and can also be unusually mature because they spend so much one-on-one time with their parents. Like first-borns, they can end up in C-level or six-figure positions, but tend to be less satisfied with their jobs than people with siblings.
... and your salary
Not only do firstborn kids tend to be smarter than laterborn kids, they're also likely to earn more money.
One 2011 paper, co-written by economist Sandra E. Black, found that the difference in average IQ between firstborn and second-born children was about three points and that it translated to about a 2% difference in annual earnings. The data came from cognitive tests administered to young Norwegian men when they enlist in the military.
If your name is easy to pronounce and common, people will favor you more
In a New York University study, researchers found that people with easier-to-pronounce names often have higher-status positions at work. One of the psychologists, Adam Alter, explains to Wired, "When we can process a piece of information more easily, when it's easier to comprehend, we come to like it more." In a further study, Alter also found that companies with simpler names and ticker symbols tended to perform better in the stock market.
Additionally, in a Marquette University study, the researchers found evidence to suggest that names that were viewed as the least unique were more likable. People with common names were more likely to be hired, and those with rare names were least likely to be hired. That means that the Jameses, Marys, Johns, and Patricias of the world are in luck.
Taller people tend to make more money and be seen as more competent
The small and average-sized among us may be short on luck.
For example, one 2004 study found that the taller you are, on average, the more you earn. According to that study, a hypothetical person who is 6 feet tall would be predicted to earn nearly $166,000 more over the course of a 30-year career than someone who's 5 feet and 5 inches tall.
Public or private school? It turns out that more expensive isn't always best
Research suggests that public schools actually outperform their costlier private peer institutions. University of Illinois professors Christopher and Sarah Lubienski published that surprising finding in their book, "The Public School Advantage: Why Public Schools Outperform Private Schools."
According to their research, students at private schools generally do well because they come from wealthy backgrounds and families with more advantages. But public schools are actually better when it comes to teaching math and keeping their teachers trained in the latest instructional methods.
Your high school math performance can predict your future salary
If you ever thought about skipping algebra class, here's a big reason not to: Higher achievement in math is correlated with a higher salary later in life.
Regardless of high school graduation status, students who complete advanced math courses like algebra II and geometry have been later found to earn $1.30 to $1.66 more per hour, on average, than students who didn't reach that level. That roughly translates to an additional $66 per 40-hour week.
Kids who play sports tend to do better academically, too
Regular exercise and participation on a sports team are both linked to greater academic performance. In one study conducted by the Los Angeles Unified School District, student-athletes were found to attend on average 21 more days of school than their peers and earn GPAs that were 0.55 to 0.74 points higher.
Other research has suggested that college students who exercise regularly get better grades, and that students who study a lot are more likely to exercise on a regular basis as well.
Military service can also shape your leadership abilities
People from military backgrounds might make the best leaders, according to a working paper from the National Bureau of Economic Research. And knowing if someone has military experience can tell you a lot about their management style.
The authors find that CEOs who've served in the military tend to be (1) more conservative financially, (2) less likely to be involved with corporate fraud, and (3) better equipped to steer firms through tough times. These findings suggest the two are linked, but can't necessarily say if one caused the other.
Healthy sleeping habits are linked to better grades
Turns out that an all-nighter probably isn't worth your time. The cost of sleep deprivation could be greater than the knowledge you might gain from studying.
Research suggests that the less high-school students sleep, the worse they tend to perform in class and on assessments. According to one study, students who receive C's, D's, and F's in school get on average 25 fewer minutes of sleep than A and B students. Again, the relationship between the two is linked, not causal: There could also be an outside, unaccounted for factor that's making students sleep less and perform less well in school.
Bosses have more favorable opinions of employees who show up to work early
Research suggests that employees who get into the office early are generally perceived as more conscientious. They also receive higher performance ratings, on average, than employees who arrive later. Even if the early-arrivers leave earlier, too, they're still viewed that way.
In one experiment, researchers recruited 149 pairs of supervisors and employees, all of whom indicated when they typically arrived to work.
Each supervisor rated their employee's conscientiousness and job performance. The researchers made sure to take into account employees' total work hours.
Sure enough, employees who typically arrived earlier were rated more conscientious and received higher performance ratings than those who started their workday later.
Another controlled experiment found that students perceived hypothetical employees as more conscientious if they got to work at 7 a.m. and left at 3 p.m. than if they got to work at 11 a.m. and left at 7 p.m. (even though both worked the same number of hours). That suggests that employees' early start times actually cause their boss to see them more favorably — and not the other way around.
Attractive people also enjoy greater career success
There's no other way to say it: Attractive people simply tend to be more successful. On average, good-looking people get hired and promoted quicker and enjoy higher salaries than their less attractive coworkers.
These findings could be partly attributable to the "halo effect," a phenomenon which refers to our tendency to assume that attractive people are all-around great people.
According to one study, more attractive CEOs also help the bottom line. Research shows that hiring an attractive CEO can boost stock prices on that person's first day and any time he or she appears on television. These CEOs also tend to fare better in M&A transactions.
A good sense of humor can help people build connections
A well-timed joke can be the quickest route to building a new relationship and can also increase productivity. Laughing and smiling produces dopamine, a neurotransmitter involved in efficiency, creativity, and engagement.
According to one study, happy employees were found to be 31% more productive and generate 37% higher sales than their peers. For leaders, humor can help to win over employees and come off as empathetic and approachable.
Using a nickname could significantly boost your salary
Believe it or not, people who go by shorter names tend to earn more money than those who don't. According to one analysis of nearly 6 million names by career site TheLadders, every extra letter in your first name can correspond to a $3,600 drop in annual wages. If you're debating between "Sam" and "Samantha," that's a big difference.
LinkedIn has conducted similar research showing that the most popular CEO names worldwide — Peter, Jack, and Fred — are either short names or shortened versions of names. So long as your nickname sounds professional, it can help convey friendliness and openness while also earning you more money.
Dressing more formally can suggest that you're confident
You might think it's superficial to focus on your outward appearance — but research suggests that the clothes you wear have a meaningful impact on the way people perceive you.
For example, in one 2014 study, adult male volunteers participated in mock negotiations over the sale of a factory. Of the volunteers assigned to the role of "buyer," one-third changed into suits beforehand; one-third changed into sweatpants and sandals; and one-third stayed in their normal clothes. (Volunteers were told that they were testing out equipment attached to the clothing.)
Results showed that the volunteers wearing suits walked away with an average profit of $2.1 million, compared to just $680,000 for those wearing sweatpants and $1.58 million for those dressed in their regular clothes.
As study co-author Michael Kraus told The Wall Street Journal, in competitive situations, dressing more formally sends a signal "about you being successful and real confident in whatever you’re doing."
Those who score high on measures of narcissism tend to earn more
Scientists are increasingly learning that so-called "dark" personality traits can help you succeed at work.
Specifically, one study found that those who score high on measures of narcissism, which is defined as having a "grandiose, yet fragile sense of the self" tend to earn higher salaries. (Note that scoring high doesn't necessarily mean you have a clinical problem.)
Researchers say narcissists often make good first impressions, especially in job interviews, so they might land more prestigious jobs than the average person. It's also possible they are more likely to initiate and succeed in negotiations.
On the flip side, being super-nice all the time may hurt your career prospects. According to data from Truity Psychometrics, "Thinkers," or those who are more analytical and logical, tend to manage bigger teams than "Feelers," or those who are more sensitive to other people's needs. Feelers also tend to be high in "agreeableness," which refers to your tendency to prioritize a group's needs over your own.
Looking trustworthy and/or dominant may help you get a higher salary
While dominance is associated with "masculine" features, like a squared face, strong jawline, pronounced eyebrows, and thin eyes and lips, trustworthiness is associated with "feminine" features, like a round face, big eyes, small eyebrows, and full lips.
For the study, 1,500 participants looked at 100 photos of male and female faces.
Participants were asked to indicate how much they would pay the person in the photograph for the position of either retail manager or head of retail operations (the latter is a more senior position).
In an earlier experiment, another group of raters had evaluated the photos for attractiveness, dominance, and trustworthiness. When the researchers analyzed all the findings, they saw that perceptions of trustworthiness and dominance mattered more among candidates for the head of retail operations job. Trustworthy-looking candidates were awarded about $419 more, while dominant-looking candidates received about $355 more.
Meanwhile, attractiveness mattered among candidates for the retail manager job.
People with deeper voices are more likely to be selected for leadership positions
Other research has found that deeper-voiced male CEOs lead larger firms and, consequently, are paid more. A 1% decrease in a CEO's voice pitch is linked to a $30 million increase in the size of his company. (The study authors admit that they can't prove having a deep voice causes people to see you as CEO material, but they think it's likely.)
Overweight people may be judged as less hirable than their thinner counterparts
Loathe as we might be to admit it, an unfair weight bias exists in the workplace.
In one experiment run by Wharton scientists, men and women rated digital resumes that included photographs of non-obese people and digitally altered photographs of those same people as obese.
Results showed that obese job candidates were deemed significantly less competent than non-obese candidates. Interestingly, even overweight participants showed a bias against obese candidates.
Other research suggests that overweight people tend to earn less than others. White women seem to be most affected by weight bias: A difference of about 64 pounds translates to a 9% decrease in wages for this demographic.
Stressed-out men tend to be less likely to be high-status leaders
A small 2015 study found that men's hormone levels may determine where on the corporate ladder they wind up. Specifically, among 78 executives, those with high levels of the hormone testosterone and cortisol managed fewer subordinates than men with high levels of testosterone and low levels of cortisol.
While testosterone is linked to competitive and aggressive behavior, cortisol is associated with stress. High levels of cortisol seem to curb the influence of testosterone, meaning that stress may hurt men's leadership potential.
"Stress reduction has leadership implications," lead study author Gary Sherman, Ph.D., told Forbes. "It can unleash leadership potential in employees who might otherwise not show it."
Extroverts and "ambiverts" tend to earn more money than introverts
Data from Truity Psychometrics reveals that extroverted personality types tend to earn higher salaries than introverted types. Specifically, the two top-earning personality types are ESTJ (which stands for Extroverted Sensing Thinking Judging) and ENTJ (Extroverted Intuitive Thinking Judging). They make average annual salaries of $77,000 and $76,000, respectively.
Meanwhile, other research suggests that ambiverts — or those who display traits of both introverts and extroverts — are the most successful at work.
For example, a 2013 study by Wharton professor Adam Grant found that, among call-center representatives, ambiverts were the most successful sales people. Those who scored exactly in the middle between introversion and extroversion on a personality test earned an average of $208, compared to an average $138 for the whole group.
This isn't to say introverts can't be successful — but they may have to try advocating for themselves in ways that feel comfortable.
Cynical people tend to earn lower salaries than relative optimists.
For example, among German participants, the least cynical people saw their monthly income increase by about 230 Euros (or around $250) between 2003 and 2012. Meanwhile, the most cynical people didn't see any significant increase in their monthly income.
Importantly, the link between cynicism and salary only holds in areas with low levels of antisocial behavior, like crime. In other words, cynics are only at an economic disadvantage in contexts where their beliefs aren't justified.
Smart kids may be more likely to become leaders as adults
Science suggests that high cognitive ability in kids strongly predicts leadership potential in adulthood.
In one study, researchers looked at two sets of data collected from nearly 17,000 people over several decades. At age 10 or 11, participants took cognitive tests that measured their verbal skills, reasoning, and general cognitive abilities. Throughout their 30s and 40s, they were also asked questions about their leadership activity at work, such as whether they supervised any employees and, if so, how many.
Results from the first data set showed that nearly four in 10 people who'd scored high on the cognitive tests went on to become leaders, compared to a quarter of those who'd scored low. Similarly, results from the second data set showed that people who'd demonstrated high cognitive ability as kids were nearly twice as likely to take on leadership positions as those who'd demonstrated low cognitive ability.
This is an update of an article originally written by Alison Griswold.
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