Draft

Opinion dynamics 2: Let’s go viral

August 30, 2020 — January 8, 2022

adaptive
collective knowledge
cooperation
culture
economics
hidden variables
how do science
institutions
mind
networks
snarks
sociology
virality
wonk

Assumed audience:

Campaigners without background in modern viral marketing

Content warning:

This entire post is about communication in a hostile environment between people of different opinions on controversial topics and links to examples of those opinions, which are, in context, potentially offensive to people of opposed opinions. Content includes guns, sexuality and religion.

1 What would a social-contagion-informed strategy look like?

Figure 1

TODO: describe how Civil society has an advantage here over corporate campaigning:

Network interventions are cheap

  • pay for themselves
  • grass roots
  • have attached business models
  • I will literally transmit beliefs in my social graph if you ask me to
  • You should ask me to transmit social beliefs in the right way and to the right people so that I do it productively

Declaration: I do not have all the answers here. In fact, no-one has all the answers here (although I suspect that some political organisations have more answers than they are sharing). Academically, this is a fresh research area, and it is not my own core research area.

But in any case, a tidy package with a bow on it is not the goal here. What we do gain by thinking about networks is a list of methods to try that just might be better if we stop assuming them away.

We are a long way into this piece, so I will just start from one. There is a sequel coming with some more stuff in it.

2 Social contagion it is where campaigners can achieve leverage cheaply

One objection I hear from campaigner friends is that it is not helpful to know about social contagion in beliefs because there is no way to influence social contagion. This is false in the strict sense; we intervene in social contagion all the time in the course of our lives, as that is what human interaction is. This blog post has likely travelled to you through some social network or other.

We might, however, admit that in any given case we may not immediately see social-network-based strategies which are fast or cheap or scalable, or some other desirable quality. Thinking back to the analogy with epidemiology, we can imagine the same objections being raised to the early germ theorists. “What use is this germ theory? It is not like it gives us any way of controlling disease.” And likely the early germ theorists, too, despaired of the possibility of teaching people to wash their hands or boil their water. Back then, though, the answer was “So let us throw that in the bin and return to treating diseases as caused by miasmas.” Rather it was to use contagion theory to decide what to investigate next and devise strategies informed by contagion models. And that is how we were able to unlock new productive methods to control disease, from public education, through to modern antibiotics and vaccines, that have radically altered our ability as a society to cope with disease.

Moreover, to discount the importance of proactive social network methods is to discount the real and sophisticated organising methods. To discount that possibility is to ignore the social-network-based opinion changes that have in fact been stewarded by many and diverse groups, often in a sophisticated fashion. Social-network-based organising has been harnessed by campaigners for queer rights, by fascists, by communists, by unionists, by gun owners, by suffragists and anti-slavery campaigners, by civil rights campaigners and by churches, and now, by trolls, marketers, terrorists and recruiters.

TODO: example citation for each use?

From another angle again, Tokita, Guess, and Tarnita (2021) suggest that intervening in social networks is how radicalisation works. In studying Twitter users they discover that people choose to self-segregate by news source. TODO - that’s polarization. connect to terrorism radicalisation pathway?

Peer pressure has complicated dynamics depending on the structure of the communities (Damon Centola 2010).

For a case study which illustrates perfectly how this plays out, I recommend the podcast Absolutely Devious Lick.

Social brain hypothesis (Bretherton and Dunbar 2020; Dunbar 1993) pro-social group behaviour (Boyd and Richerson 1992; Richerson, Boyd, and Henrich 2003)

How good are we at forming good facty beliefs? Scott Alexander discusses the irritating case study of bodybuilders suggests…. tl;dr: We are not very good at facty beliefs?

Figure 2

Via Byrne Hobart, Odlyzko and Tilly (2005):

This note presents several quantitative arguments that suggest the value of a general communication network of size \(n\) grows liken \(n\log(n)\). This growth rate is faster than the linear growth, of order \(n\), that, according to Sarnoff’s Law, governs the value of a broadcast network.On the other hand,it is much slower than the quadratic growth of Metcalfe’s Law, and helps explain the failure of the dot-com and telecom booms, as well as why network interconnection (such as peering on the Internet) remains a controversial issue

An interesting phenomenon happens with free speech;

Persuasion is a publication and community for everyone who shares three basic convictions:

  • We seek to build a free society in which all individuals get to pursue a meaningful life irrespective of who they are.
  • We believe in the importance of the social practice of persuasion, and are determined to defend free speech and free inquiry against all its enemies.
  • We seek to persuade, rather than to mock or troll, those who disagree with us.

In the past years, the political and intellectual energy has been with illiberal movements. Too often, the advocates of free speech and free institutions have been passive, even fatalistic. It is high time for those of us who believe in these enduring ideals to stand up for our convictions.

Or, more exotic for me, Open Source Defense — “100% gun rights, 0% culture war”.

The most generous interpretation of these projects, which I personally incline to, is that here are some individuals who truly wish to engage across the political spectrum, burst filter bubbles and make society as a whole work as a collective project (even though they might disagree with me about some details). The least generous interpretation of those projects is that they are lead by people pushing malign agendas who wish to make the other side look shrill and aggressive. Of course, we can have both. Whichever you believe is their intent, if you believe these projects have a chance of success, the rational response seems to be to meet their onslaught of openness, reason and curiosity with openness, reason and curiosity of your own.

In fact there are variants strains of social contagion hypotheses in circulation, depending how broadly or narrowly we define the terms here, but I think we can gloss over that for now.

There is another concept that is very useful here:

Social graph
My social graph is who I talk to; my family, my friends, my co-workers, my co-religionists, the people I argue with on the internet, etc. We can also refer to this as my “social network” but If I say that, it sounds like I am talking only about Instagram or Facebook or something purely technological. Those internet-based social networks represent one important type of social graph, but not the only one.

Why do we want to think about social graphs? Because these are where we get opinions from.

For a small number of people, who study bushfires, or who live through them, or who suffer from a serious COVID-19 (or vaccine) side effect, their information is not so much a political opinion; they have information of different kinds. But for most of us, our information about these society-wide problems and responses is a political opinion.

For a smaller number of people, who study bushfires, or who live through them, or who suffer from a serious COVID-19 (or vaccine) side effect, their information is not so much a political opinion; they have information of different kinds. But for much of the public, our information about these society-wide problems and responses is a political opinion. And those political opinions, although we might think otherwise, are transmitted to us through our social graph. Let us look at some of the evidence about this.

This is how doing something to fit in with our peers can feel like taking a stand against a society gone mad.

We often get this wrong. I get this wrong every time I try to change a relative’s mind by arguing with them about something; Every time I do that I am falling prey to the fallacy that they (or I) get opinions from argument. I am not saying persuasion of this sort never happens, but certainly being persuaded by argument is an infrequent occurrence for me, if I am being honest with myself, and it is slow hard work for the poor soul who seeks to persuade me.1

Outgroup biases mean that it is hard for us to have good models of how other people form their own beliefs; those people in that group all think alike. They are not diverse and independent-minded like us over here. Pro-tip: Everyone in every group thinks that, and few of us have data to back it up.

Starting Not Your Imagination— Society Is Going Insane and I Can Prove It

  1. We underestimate how social our beliefs are

  2. the social networks through which we get our opinions are hard to reason about

  3. as a result, we operate on other models

    1. rhetorical persuasion
    2. opinion dynamics are a property of who you are (ethnic group, economic status…
    3. Personality “types”, intrinsic “values”
  4. By focusing on those effects we tend to discount a more important effect, which is that social networks can explain most of what we belief

For bonus time we could consider persuadability, evidence from influencers, and data from the internet, covariates like in-group membership and status, etc. We can muddy the waters by talking about how homophily and contagion are indistinguishable by observation; mention the obesity question.

I do not notice social contagion. Social contagion feels like

(Goel, Mason, and Watts 2010):

It is often asserted that friends and acquaintances have more similar beliefs and attitudes than do strangers; yet empirical studies disagree over exactly how much diversity of opinion exists within local social networks and, relatedly, how much awareness individuals have of their neighbors’ views. This article reports results from a network survey, conducted on the Facebook social networking platform, in which participants were asked about their own political attitudes, as well as their beliefs about their friends’ attitudes. Although considerable attitude similarity exists among friends, the results show that friends disagree more than they think they do. In particular, friends are typically unaware of their disagreements, even when they say they discuss the topic, suggesting that discussion is not the primary means by which friends infer each other’s views on particular issues. Rather, it appears that respondents infer opinions in part by relying on stereotypes of their friends and in part by projecting their own views. The resulting gap between real and perceived agreement may have implications for the dynamics of political polarization

Some of our preferences clearly are pretty hard wired in and come from some other place (god? genes? zodiac?). We don’t really need to worry about THAT here though, because opinions are more like roller skates than sexual orientation. That is, they are more like fashion items than hard-wired choices.

Antonio García Martínez, in The Holy Church of Christ Without Christ, belabours the point that faith-based engagement is how we predominantly engage with the world. Or, as Herbert Simon and Eliezer Yudkowsky could have co-authored, belief is how a heuristic feels from the inside.

When it comes to statistics, we understand bucket models very well and have been working with them for a long time. This makes sense when you look at all the early successes of statistics in agriculture and industry going back more than a century. If you are trying to learn which breed of cow is best keep on your farm, then it makes sense to analyse cows in terms of which breed/bucket that cow comes from.2

Social network models are much newer and less well understood, but they are also very important. A big example from recent history is epidemiology, the study of the spread of a disease. If I try to understand my risk of catching a disease by a bucket model, then I am throwing out much useful information. To work out my risk of catching COVID-19, for example, there is some information in which demographic bucket you can assign me to, but really, the most informative bit of information about my risk of catching COVID-19 is whether i have been in contact with someone else who was the disease. That is, COVID-19 spreads along certain connections in my social graph.

And indeed we should expect the similarity to viruses to not be absolutely perfect for every possible idea. There is no literal physical bacterium or virus which transmits ideas around in little strands of RNA or DNA.

OK, what exactly do I mean here by social contagion of beliefs? Do I mean that ideas are literally like viruses, and that there is some tiny molecule that carries belief from one person to another? Absolutely not. The ways that contagious beliefs are like contagious diseases is in their broad-brush behaviour. Ideas can rapidly spread from person to person, and the greater the contact the greater the potential is for transmission. If two groups are very separated they will not transmit ideas, and so on. ou get the idea. Opinions and viruses can both be described very well in terms of epidemiology. Just we understand how disease spreads by looking ant person-to-person contact, so do we with ideas.

The overarching theme is that to understand why people believe things you need to see who they hang out with.

I disagree. In fact it is one thing that we can do. Walking down the street to talk to someone new is within the reach most citizens.

Points to touch upon:

The problem with models of people’s intrinsic personality types and values are several

  1. we cannot ethically do brainwashing experiments or removing individuals from their communities, so our data is usually fairly observational; we do not know how hard it is to change a fundamental value
  2. Research about stability of personalities is complicated and fraught (Big 5 traits are a mess, there are probably things that are stable about people over time but we don’t know how to disentangle that from their communities)
  3. Even if we know what is stable over time, there is no God-given mapping from a small local personality trait to a nebulous massive confusing contested complicated thing like a mass-scale policy; Different policies get their values from how and by whom they are presented not by any intrinsic quality (If I ask what the preference for a given marginal tax rate for a given income bracket should be for a given vote conditional on their measured values of Agreeableness and Neuroticism, what will you tell me?)

Do we need to go into HPS and observational experiments here?

Return to earlier example.

It has been battle tested and weaponised.

2.1 Bringing people together in common cause

Figure 3: Jesus’ social network by Jennifer McClure

Even if you have personal qualms about the stringency of the sampling methodology used in biblical tales, the bible has served as an excellent blueprint for recruiting for many churches throughout history.

2.2 Let’s go viral

In a social-contagion informed policy we start by considering what it means to go viral. We care less about whether someone responds to a message per se than we care about how likely they are to pass on a message, and who they will pass it on to, and how.

Figure 4

Here we want to know if things are retweetable.

Hayward (2005) explicitly uses an epidemic model to study the growth of churches, where the growth or stagnation of the church is due to the contagiousness of recruits in their infectious phase.

Caveats: Watts and Dodds (2007) finds that influentials are defined relatively; if people are easily persuaded to take on a new idea it might be worth identifying the influencers in the network, but for entrenched ideas, might want to try other methods.

Weak ties and superspreaders (Bakshy et al. 2012; D. Centola and Macy 2007; Granovetter 1973)

2.3 The policy victory is the friends we made along the way

Making friends is the most powerful intervention we know to change people’s minds

Peer networks overwhelm almost anything else in determining beliefs if they can be mobilised.

Are you worried about your opponent’s advertising campaign? Thanks to terrorist radicalisation research, we know that peer ties stronger than advertising (Reynolds and Hafez 2019). Also, thanks to the well-studied QAnon and Antivax movements, we know that strong peer maintenance of a narrative can overwhelm a massive press barrage.

Popular in the study of health interventions. Straight up health interventions are especially well studied here. Reviews like Hunter et al. (2019) are unambiguous: “We recommend that the scientific community should move beyond individual-level approaches to design and test interventions that use the largely untapped potential of social networks to improve health behaviours and outcomes.”

Actual opinion leaders are better identified by communities themselves Valente (2006)

Famous paper (Rogall 2014) argues that face-to-face organisation was essential to perpetrate the Rwandan genocide. (Response to prior argument that the media was enough (Kellow and Steeves 1998).)

There is obviously less money for conservation-related studies. but see, e.g. de Lange, Milner-Gulland, and Keane (2021).

Intriguingly, some of the larger studies (Kim et al. 2015; Valente 2006) suggest that one thing that does not work well is for an outside observer to choose who the influencers/thought leaders are; what works much better is “peer nomination” methods. That is, even with deep reporting of the peer networks to researchers, the people in the network still intuit who to reach out to better than the researchers.

3 Correlation and causation and conditioning

Recycle some of the examples highlighted by Gwern correlation

3.1 Weak ties and connecting communities

Bridging communities is high value. This is well-studied in the context of church recruitment (Bretherton and Dunbar 2020; McClure 2021; Hayward 1999, 2005).

Figure 6: Weng, Menczer, and Ahn (2013)

Famously Burt (R. S. Burt 2002; Ronald S. Burt 2004) argues that bridging holes in the network gives the briding indivuals who do so high power.

Also the types of belief and the types of network relations can interact (Damon Centola 2010; D. Centola and Macy 2007). It can mean several different things for an idea to transfer between two humans.

4 Incoming

Chaotic notes vying for a place in the body text.

Segmentation faults: how machine learning trains us to appear insane to one another. Semi-counterpoint: Doctorow on Big Tech narratives.

Figure 7: If all you have is demographic segmentation, you have awkwardness.

Other factors:

Thinking things through
Of course people sometimes think things through and we humans do sometimes come to our own conclusions. However it is hard for campaigners and policy nerds to appreciate how rarely people do this. It is not a never thing, it is just that the number of policies people Think through per week are low, because things are, for most people, competing with Netflix and
Rational discussion
You might believe that people are rational and won’t take on strictly ridiculous opinions. This is largely unimportant in the current setting. I cannot get people to believe that fire is not hot, but that kind of thing was already ruled out at the start because the hotness of fire is not a political opinion. More generally though, some policies are surely sillier than others and all things being equal, it is not crazy to suppose that people might prefer less silly policies. Having seen the kind of policies we will regularly vote for, and the policies people will argue for over dinner, I think that this effect is probably weak and easily overwhelmed by more powerful forces. For the purposes of campaigning, this effect is not relevant. Remember, we need to persuade a voting majority of the population, not just small fraction of us that are nerds and wonks with enough time to discuss every issue.
Advertising
Yes, mass advertising probably has an effect on us, and because politics is a delicately balanced matter. However, as advertising bleeds into social influence more generally, this distinction gets less interesting.
Hip pocket
OK, there is evidence that people do evaluate the cost to themselves of various policies, so I am not going to argue that this is unimportant. On the other hand, how important people think any given policy, and whether they spend the mental effort on “running the numbers” on any given policy against their own financial plan and how willing their are to be generous, whose modeling is considered legitimate, this is all modulated through what their peers bother to do, even here we might consider the modulating effect of social graphs. People vote for economic insanities all the time.
Some things are innate
Clearly some things are not massively socially contagious. Sexual orientation does not appear to be especially socially-transmissible, for example. The number of people who claim to be turned gay (or straight) by a friend, or a particularly good podcast, might not be zero, but it is small.

In the world, other theories of what people believe and why are in play.

TBH I am not across all the varied theories that people have for why the population at large has the opinions they do. I have heard of theories that include intrinsic values, and personality types and demographic categories, which zodiac sign a person was born under, which Myers-Briggs personality type etc. There are surely many others. These all have differing degrees of evidence to support them, and differing degrees of usefulness in different contexts. I am not going to attempt to address all of these here; that is a whole project of its own.

Figure 8
Figure 9

Status, prestige, trust. Timing. Tribal identification.

Figure 10: Here we can imagine that each circle represents a person, and they are grouped into support for two different parties, the red party and the yellow party.

Previously in opinion dynamics, we discussed the importance of social graphs in understanding belief, and the high likelihood that if we are trying to intuit our way through understanding society, we are likely to underestimate the importance of those social graphs to forming opinions in ourselves and in others.

Oncoming onslaught of fake news and autogenerated content. GPT4 etc, Microsoft is Playing with Fire GPT-4

Figure 11

Alternative models

  • Targeted advertising
  • Rational discussion
  • values
  • economic decisions, personal
  • demographics
Figure 12
  1. Data collection
  2. homophilous networks
  3. weak ties/small worlds
  4. Targeting key nodes

Until we had the understanding of contagion, we did not even have the ability to recognise this distinction between the contagious and the non-contagious, and were cursed to be ineffectual at controlling contagious diseases.

The people going into labs to do social psychology experiments are not any stupider than me on average. They are having the completely normal human experience that I also have, which is thinking that I am (they are) clear-sighted and perceptive, and other folks are sheeple.

In Australia we have a version of this.

5 References

Bakshy, Rosenn, Marlow, et al. 2012. The Role of Social Networks in Information Diffusion.” In Proceedings of the 21st International Conference on World Wide Web. WWW ’12.
Boyd, and Richerson. 1992. Punishment Allows the Evolution of Cooperation (or Anything Else) in Sizable Groups.” Ethology and Sociobiology.
Bretherton, and Dunbar. 2020. Dunbar’s Number Goes to Church: The Social Brain Hypothesis as a Third Strand in the Study of Church Growth.” Archive for the Psychology of Religion.
Burt, Ronald S. 2002. “The Social Capital of Structural Holes.” The New Economic Sociology: Developments in an Emerging Field.
Burt, Ronald S. 2004. Structural Holes and Good Ideas.” American Journal of Sociology.
Centola, Damon. 2010. The spread of behavior in an online social network experiment.” Science (New York, N.Y.).
Centola, D, and Macy. 2007. “Complex Contagions and the Weakness of Long Ties.” American Journal of Sociology.
de Lange, Milner-Gulland, and Keane. 2021. Effects of Social Networks on Interventions to Change Conservation Behavior.” Conservation Biology.
Dunbar. 1993. Coevolution of Neocortex Size, Group Size and Language in Humans.” Behavioral and Brain Sciences.
Goel, Mason, and Watts. 2010. Real and Perceived Attitude Agreement in Social Networks.” Journal of Personality and Social Psychology.
Granovetter. 1973. The Strength of Weak Ties.” The American Journal of Sociology.
Hayward. 1999. Mathematical Modeling of Church Growth.” The Journal of Mathematical Sociology.
———. 2005. A General Model of Church Growth and Decline.” The Journal of Mathematical Sociology.
Hunter, Haye, Murray, et al. 2019. Social Network Interventions for Health Behaviours and Outcomes: A Systematic Review and Meta-Analysis.” PLOS Medicine.
Kellow, and Steeves. 1998. The Role of Radio in the Rwandan Genocide.” Journal of Communication.
Kim, Hwong, Stafford, et al. 2015. Social Network Targeting to Maximise Population Behaviour Change: A Cluster Randomised Controlled Trial.” The Lancet.
McClure. 2021. Congregations of a Feather? Exploring Homophily in a Network of Religious Congregations.” Review of Religious Research.
Odlyzko, and Tilly. 2005. “A Refutation of Metcalfe’s Law and a Better Estimate for the Value of Networks and Network Interconnections.”
Powell, and Weisman. 2018. Articulating Lay Theories Through Graphical Models: A Study of Beliefs Surrounding Vaccination Decisions.”
Reynolds, and Hafez. 2019. Social Network Analysis of German Foreign Fighters in Syria and Iraq.” Terrorism and Political Violence.
Richerson, Boyd, and Henrich. 2003. “Cultural Evolution of Human Cooperation.” Genetic and Cultural Evolution of Cooperation.
Rogall. 2014. Mobilizing the Masses for Genocide.”
Tokita, Guess, and Tarnita. 2021. Polarized Information Ecosystems Can Reorganize Social Networks via Information Cascades.” Proceedings of the National Academy of Sciences.
Valente. 2006. Opinion Leader Interventions in Social Networks.” BMJ : British Medical Journal.
Watts, and Dodds. 2007. Influentials, Networks, and Public Opinion Formation.” Journal of Consumer Research.
Weng, Menczer, and Ahn. 2013. Virality Prediction and Community Structure in Social Networks.” Scientific Reports.

Footnotes

  1. Certainly I am not relying on mere argument to persuade you, my audience. I do not expect that you will really read all the links and articles I have mentioned here (although, please do). Rather, I am writing this for people who are in my extended social circle to read, and name-dropping a few fancy authorities to grant my peer recommendation the force of authority. Any extra persuasion-of-strangers-by-force-of-argument that happens after that is a bonus.↩︎

  2. And to be fair, I smushing many diverse types of models together into “buckets” here in a slightly unfair way, but I think this gives the flavour of the idea. Real-world models have some very fancy buckets, and allow people to be in multiple buckets, or partially in buckets, or high-dimensional bucket spaces or whatever. I do not think raising those options necessarily changes much here, and what I really want to get at is the graph sampling and causality problems that we need to think about differently between network and classical independent methods.↩︎