Friday, October 29, 2010

Liberal Gene

Jonah, via Maggie.

The finding is that a particular gene, plus having a lot of friends in adolescence, correlates with having politically liberal ideas as an adult. Sounds possible.

The kicker is the hypothesis by "the researcher and his colleagues" is the kicker:
people with the novelty-seeking gene variant would be more interested in learning about their friends’ points of view. As a consequence, people with this genetic predisposition who have a greater-than-average number of friends would be exposed to a wider variety of social norms and lifestyles, which might make them more liberal than average.
The far-more obvious possibility, that people who seek social approval become liberals, does not even occur to them.

When adolescents eat more, or drink more, have too much or too little sleep, too many or too few sexual partners, or do anything outside the statistical norm, the focus immediately goes to some greater need for something-or-other that explains the behavior.

Or when children in studies have certain personality traits and grow up to be conservatives, we are treated to hypotheses of their greater need for control, or rules, or conformity, or some other pathological explanation. But since they grew up to be liberals, whatever they did that was different must obviously be something good.

What the hell is it with these people? They are supposed to, by profession, be alert for outside factors that bias their results.


Sponge-headed ScienceMan said...

What the hell is it with these people? They are supposed to, by profession, be alert for outside factors that bias their results.

Ummm, and liberal, grant-funded climate scientists should leave group-think at the door. I'm not holding my global-warming breath.

Dr X said...

You're putting the following hypothesis forward: need for social approval (NSA) mediates the interaction between the "novelty-seeking" gene and the number of friends a person has. That interaction is as follows: neither the gene alone nor the number of friends predicts liberalism. The two combined (higher number of friends and the gene) predict liberalism. So the two variables (genetic and environmental) are not additive influences. Rather, they are mutually potentiating.

Are you saying that NSA is explains this interactive relationship? If that’s what you’re saying, I don’t follow your reasoning.

I can follow the reasoning behind the authors' hypothesis. The reasoning goes like this: one can have the novelty-seeking gene, but if that person doesn't have a large number of friends, the opportunity for novel stimulation isn't there. On the other hand, one can have many friends, but if one isn't biologically inclined toward novelty-seeking, no novel stimulation will be sought from the pool of novelty opportunities.

Here's an analogy. A person with a novelty-seeking gene might live next door to a library. Such a person might be more likely to make use of the library next door and become more well-read. A person without the novelty-seeking gene may live next door to the library, but make little use of it. Now let's change the environment: A person with a novelty-seeking gene might live in prison cell with no access to a library. That person will not become more well-read, even though they have the novelty-seeking gene. The desire for novelty is there, but the pool of opportunity to become more well-read is much smaller. So neither the gene alone nor the environment (availability of books) predicts being well-read. Only the presence of both predicts being well-read. This would not be an additive relationship between gene and environment; it would be a gene-environment interactional (mutually potentiating) relationship. The mechanism potentiating the interactional effects of gene and environment would be reading.

The authors put forward such a hypothesis; made a prediction based on the hypothesis; gathered and analyzed the data; and the finding failed to disconfirm their hypothesis. The predicted relationship was found. That’s how it works. The proposed mechanism that spawned the hypothesis might be yet be proven false, but it withstood what would be the first predictive test that must be done. There is no other way I know of to conduct research than this.

You’ve introduced a third variable into the mix: need for social approval. So now there are three variables: presence of absence of the novelty-seeking gene, number of friends and need for approval. You’re saying that the last mediates [predicts] the relationship between the first two? How? How does this mediating variable (NSA) predict the interactional effect exerted by the gene and the number of friends [on degree of liberalism]? I've been thinking hard about this and I don't see how NSA might predict the interaction.

Need for social approval might predict liberalism, but that’s probably a matter independent of the interactional effects of the gene and number of friends. In other words, it’s a different experiment testing a different influence on ideology. Remember that this study did not claim that the interaction between the gene and the number friends is the sole determiner of liberalism. It merely proposed and found that the interaction is one measurable factor. Another factor might, indeed, be need for social approval. Determining whether that is so would require an entirely different test. Surely ideology is related to multiple factors, including factors that remain unknown. There is plenty of research indicating exactly that.

Assistant Village Idiot said...

I'm part-way with you on this, Dr. X. My objection was not to the entire study, which seems to have something to it, but the place where they stepped out into hidden assumptions.

First, you are right that my oversimplification leaves out the part about the presence of the gene being prior. I get that, but you wouldn't know it from what I wrote.

But they make two leaps "people with the novelty-seeking gene variant would be more interested in learning about their friends’ points of view." That does not follow. That is a possible explanation, but there are others: there are other novelties besides POV that may be desired. If it were POV that was being sought, the library would provide it better. So would hanging around with people older than themselves; so would movies and TV, actually.

Additionally, the researchers assume that more friends mean more POV's. Not necessarily. Adolescents cluster to their groups, and their church youth group, soccer team, or school chorus might in fact embed them in a whole set of unexamined assumptions. We can all see how having more friends might expose them to more POV's, but that is not established, and there is at least some trend in the opposite direction.

I may be describing myself and my own friends when I note this. I sought novelty, had a huge circle of friends, was very liberal, and now understand that to be a need for social approval, both in myself and in my friends. So I don't say that is the most likely explanation, but I know for certain that it is one that occurs in reality.

Second, the researchers make the similar assumption that liberals are more comfortable with different POV's. That is not my general experience. I don't find much of anyone comfortable with different POV's, though lots of folks point to superficial differences as evidence that they are. The differences are carefully selected. I am not in any way suggesting that groups other than liberals are better at this. (Not here, anyway.) That would be extremely difficult to measure, and would probably focus on exactly the superficial differences on which we deceive ourselves.

As to adding in Need for Social Approval as a new variable, yes and no. I think that as a general rule the categories "more friends" and "need for social approval" overlap strongly, and I make a leap of my own when I assume that the latter enters the discussion whenever the former is established. They are not an exact match, and those with the novelty-seeking gene may turn out to be many of the exceptions. But that is not established.

Finally, I was thinking of research like this, which is your basic Fish. Barrel. for ease of criticism. Not that there is nothing to it, but that it is rife with jaw-dropping assumptions. I speculated - and this is my bias - that if those adolescents had turned out to be conservative instead of liberal, some equally uncertain hypothesis would have been offered, such as more friends indicating a greater devotion to group norms. Hypotheses like these are an easy game to play.

Postscript: If I wasn't clear, the study itself may be valuable. That gene plus more friends may indeed activate liberalism, and that would be worth knowing and worth knowing why.

Sam L. said...

Indeed, AVI, given NPR's firing of Juan Williams, it appears that liberals/progressives don't abide different POVs.