In order to predict someone's opinion -- on, for instance, Trump, or marijuana legalization -- is it better to know their age or in what year the question is asked? Does our upbringing influence our cultural choices ... or do we change with the times?
Consider two shifts in cultural values. First, have you noticed the music you turn to for “sonic comfort” is frequently the music of your youth? 
Second, several years ago, to improve the hospital’s “safety culture,” physicians were required to not only date their notes but also write down the time they wrote them. That small cultural shift evidently crossed some regulatory red-line, and some physicians just would not do it –– or did it only when “caught.” I remember discussing the problem with a colleague, who pointed out that this problem of compliance would not change until those physicians were “dead,” meaning when they left clinical practice. A recent paper strongly suggests that she was on to something.
“If we want to predict (say) a person’s opinion on an issue, or their behavior, would we do better to know what year it is when we ask the question, or what year the person was born?”
Our changing social behavior results from the interaction of three factors. The first is the biological imperatives and restraints we associate with age – for instance, we party quite differently at 20 and 70. Second, we have the sentinel cultural events of our past, which is where music fits in. But it is equally true for the effects of the “Depression,” particularly on the spending behavior for those from the "Greatest Generation." Finally, there are contemporaneous changes, the #MeToo movement or the growing acceptance to legalize marijuana. Which of these forces is the real driver of cultural change?
The sociologist-authors offer up two competing theories.
In the cultural fragmentation model, current meanings are predominant. In acquired disposition model, like the baby duck, we are imprinted in the formative years. And it is these cultural meanings we carry through life as our preferences. (SPOILER ALERT: As you might expect, it is not either/or, but the relative importance of the two effects.)
The authors' fundamental assumption was that they could measure and separate the two models by looking at how the beliefs of a cohort –– based on age –– varied over time compared to the changing beliefs of the entire population in the same interval. That is known as a period effect.
To get at the answer, they made use of the General Social Survey (GSS), a longitudinal study of our opinions since 1972, conducted by the University of Chicago’s National Opinion Research Center. It contains a “standard core of demographic, behavioral, and attitudinal questions, plus topics of special interest.” They looked at 164 various topics surveyed from 1972 until 2014, looking at the changing views by both the cohort and the population as a whole (aka, the period). Along the way, they structured “cultural durability,” their measure of changing beliefs. A value closer to one was primarily due to an age cohort; a value closer to zero was due to a period effect.
- For most topics, cohort effects dominate – acquired dispositions is the dominant driver
- Items with high cohort effects are more often core “value” items, attitudes toward civil liberties, tolerance, gender roles – values we have internalized in our formative years, in the past.
- Items with high period effects, the contemporaneous were more frequently consideration of external political or economic issues, e.g., political views, confidence in the legal or political system, and legalization of marijuana.
So, to answer the question the researchers posed, to best guess a person’s opinion one should ask them their age. From a cultural standpoint, shifting opinions are a blend of what we have been taught and how many of us share those beliefs. The cultural beliefs of society are more often, to use an economic term, lagging indicators, reflecting what the dominant generations were taught.
This does not mean, as my colleague suggested earlier in this piece, that we must wait for the old ideas and their carriers to die, does it?
It isn’t necessarily a linear model, with incremental decreases in believers in lockstep with gradual reductions in belief. To draw a metaphor from the hard sciences, as the relationship between old and new beliefs changes, there may come a phase shift when suddenly the period effect predominates, when our perception of the opinion of others overrides our imprinting.
Much like “overnight sensations” who have worked in their fields for decades before sudden acclaim, it seems that cultural shifts may be more the result of how we are raised than by any magically persuasive argument we can offer in a particular moment.
 One need not look further than Broadway for the answer. Among the current hits are shows featuring the life and songs of Carole King, Cher and Donna Summer respectively.
Source: Cultural Fragmentation or Acquired Dispositions? Socius DOI: 10.1177/2378023116669726