While we have known that explicit biases change over time, there have been some doubts about whether our more deeply held implicit biases can shift as well. The authors’ new research shows, for the first time, that the implicit attitudes of a society can and do change durably over time — although at different rates and in different directions depending on the issue. Drawing on data from over 4 million tests of explicit and implicit attitudes collected between 2007 and 2016, they found that Americans’ implicit attitudes about sexual orientation, race, and skin tone have all decreased meaningfully in bias. They also found some areas, such as attitudes about weight and disabilities, in which the news is not so positive.
From Puritan America through much of the 19th century, a same-sex relationship was punishable by death; today same-sex marriage is federally legalized. In 1937 only 33% of Americans believed that a qualified woman could be president; in 2015, 92% endorsed the possibility. In 1958 only 4% of white Americans approved of black-white marriages; today 87% of white Americans do. These findings highlight the fact that our minds can and do change toward greater equality of opportunity. This is good news for business leaders, since greater diversity has many benefits for organizations. For example, it allows the best talent to emerge, makes teams smarter, and improves financial performance.
As early as the 1930s, surveys such as those from Gallup, the General Social Survey, and Pew Research documented long-term changes in attitudes and beliefs about social groups, especially those involving gender, sexual orientation, race, and ethnicity. These attitudes and beliefs, measured via self-reports on surveys, are widely referred to today as explicit attitudes and beliefs, because they reflect conscious recollection and controllable reports of the contents of one’s mind.
But self-reports have limitations. Respondents may be unwilling to divulge their attitudes (because they want to be seen as giving the “right” answer), or they may be unable to report their attitudes (because of a lack of awareness of their own minds). In response, scientists developed indirect methods to measure relatively less controllable and less conscious attitudes, known as implicit attitudes. For example, the most widely used test of implicit attitudes — the Implicit Association Test, or IAT — uses people’s response times to categorize certain stimuli as an indirect measure of their attitudes toward those stimuli. Crucially, both explicit and implicit attitudes have been demonstrated to influence behavior, including workplace decisions like hiring.
Because they are less controllable, it was assumed that implicit attitudes would be more difficult to change than explicit attitudes. Indeed, previous studies focusing on the short-term flexibility of implicit attitudes showed that, while some interventions shifted an individual’s implicit biases momentarily, the changes typically did not last, some snapping back after only one day.
Our new research shows, for the first time, that the implicit attitudes of a society can and do change durably over time —although at different rates and in different directions depending on the issue. Drawing on data from over 4 million tests of explicit and implicit attitudes collected between 2007 and 2016, we found that Americans’ implicit attitudes about sexual orientation, race, and skin tone have all decreased meaningfully in bias over the past decade. We also found some areas (age, disability, and body weight) for which the news is not so positive.
Our data was from 4.4 million IATs and self-reports collected at implicit.harvard.edu. To analyze it, we employed statistical models similar to those used to analyze and forecast market trends in economics, and applied them to the study of attitude change over time. We also performed additional analyses to control for several possible explanations for our results, such as changes in the sample over time (for example, the possibility that the sample had become younger).
Some Attitudes Are Changing for the Better
The data reveals how certain attitudes in American society changed from 2007 to 2016. Implicit anti-gay, anti-black, and anti-dark-skin attitudes have all shifted toward neutrality. Implicit attitudes about sexual orientation showed the fastest change, with anti-gay bias decreasing by 33% over the 10-year period. This change is not only fast, but is also steady: The model predicts consistent decreases over time, such that anti-gay bias could reach complete neutrality (zero bias) between 2025 and 2045 – which for many of us is within our lifetimes. Moreover, this change is widespread: It is present among men and women, straight and gay people, young and old people, and liberals and conservatives, although liberals and young people show the greatest movement.
Implicit attitudes toward race and skin tone have also moved toward neutrality, by 17% and 15%, respectively — progress that, while not nearly as rapid as that of anti-gay bias, is noteworthy given the 10-year period of observation. For both attitudes, this change has been particularly rapid in recent years, with a visible inflection point showing faster change since approximately 2012 to 2013.
For now, we can only speculate as to why attitudes about sexual orientation are changing so quickly and consistently relative to other attitudes. First, sexual preferences can be concealed, whereas concealing race or skin tone, for example, can be harder. Gay people, for example, can develop personal relationships with neighbors and friends or even their parents without revealing their sexual orientation. When close friends or family members discover that someone they know and love is gay, those with negative views about that sexual orientation may be motivated to change their minds. Take, for example, the case of U.S. Senator Rob Portman, who began supporting same-sex marriage after his son came out as gay.
Second, it is possible that implicit attitudes about sexual preferences are changing rapidly because differences in sexual orientation are present in all parts of society, including across boundaries of socioeconomics, race, ethnicity, religion, and geography. Such widespread opportunities for positive contact may motivate changes of attitude — which is not the case for attitudes toward race because segregation has impeded the spread of racial diversity. Finally, the rapid change in attitudes about sexual orientation may also be driven by numerous recent legislative advances, positive portrayals in the media, and widespread activism around the issue.
Some Attitudes Have Remained Stable or Become More Negative
Our data does not show progress across the board. Some implicit attitudes have remained stable over the decade: Negativity toward the elderly and people with disabilities has shifted by less than 5% since 2007. In fact, change is so slow that forecasts suggest it could take well over 150 years for either bias to reach neutrality. Unlike sexual preference and race, ageism and ableism are relatively under-the-radar attitudes when it comes to social and legal engagement. Both are also related in people’s minds to actual physical traits that are easy to see, and many of which are perceived negatively.
Implicit weight bias (pro-thin/anti-fat) increased by 40% in the early years of the decade, approximately between 2004 and 2010. These increases stand in stark contrast to the decreases observed in explicit weight bias as well as to all other implicit biases we studied, which, at worst, have remained stable. We think the increasing attention to the health benefits of lower body weight and concerns about the obesity epidemic may be responsible for the increase in bias. Additionally, the perception that body weight is always under one’s own control (race, sexual preference, age, and disability, on the other hand, are not) may lead to harsher attitudes toward those who are overweight.
Whatever the causes of changes in implicit attitudes, business leaders seeking to widen participation rates and gather the best talent in their organizations must not forget the subtle forms of bias and discrimination that exist today, especially given the stability and even the deepening of some implicit attitudes over time. Nevertheless, the fact that some biases ebbed over a 10-year period is cause for hope: It shows that even seemingly automatic biases can and do change.
Of course, such progress does not happen on its own. As managers, researchers, educators, policy makers, and citizens, we can use this research to propel deliberate thought and consciously enacted policies that will motivate behavior and attitude change in the direction of what we, as a society, desire for our future.