Sunday, November 1, 2020 | ePaper

Polarization Rational In Politics

  • Print
Kevin Dorst, PhD :
A striking feature of polarization is that it's predictable. If you're a liberal, you can predict that you'll continue to become more confident that Trump is a bad president; if you're a conservative, vice versa.
Does this mean that polarization is due to irrational causes? Recently I described a result suggesting it does: in standard models of rational belief, predictable polarization is impossible.
But there's a catch: those models (implicitly) assume that evidence is always unambiguous, in the sense that you should always know what to make of it. This isn't true of real-life politics. Often you should be unsure what to think: for instance, you might wonder to yourself, "Am I right to be confident that Biden will win the election -or am I being overconfident?"
That raises a question: what happens to that theoretical result once we allow for ambiguous evidence?
The key result driving this project is that ambiguous evidence can lead to predictable polarization:
Fact. Whenever evidence is ambiguous, there is a claim on which can be predictably polarizing. (The Technical Appendix contains all formal statements and proofs.)
In other words, someone who receives ambiguous evidence can expect it to be rational to increase their confidence in some claim. Therefore, if two people will receive ambiguous evidence, it's possible for them to expect that their beliefs will diverge in a particular direction.
As I demonstrated in an experiment - and as I'll explain in more depth next week-this means that ambiguous evidence can lead to predictable, rational shifts in your beliefs.
Without going into the formal argument, this is something that I think we all grasp, intuitively. Consider an activity like asking a friend for encouragement. Suppose you just interviewed for a job, but you're nervous and come to me seeking reassurance. What will I do?
I'll provide you with reasons to think you will get it-help you focus on how your interview went well, how qualified you are, etc.
Of course, when you go to me seeking reassurance you know that I'm going to encourage you in this way. The mere fact that I'm giving you such reasons isn't, in itself, evidence that you got the job.  Nevertheless, we go to our friends for encouragement in this way because we do tend to feel more confident afterward. Why is that?
If I'm a good encourager, then I'll do my best to make the evidence in favor of you getting the position clear and unambiguous, while that against you getting it unclear and ambiguous. I'll say, "They were really excited about you in the interview, right?"-highlighting unambiguous evidence that you'll get the job.  And when you worry, "But one of the interviewers looked unhappy throughout it," I'll say, "Bill? I hear he's always grumpy, so it's probably got nothing to do with you." Thus making evidence that you didn't get the job more ambiguous and so weaker. On the whole, this back-and-forth can be expected to make you more confident that you'll get the job.
This informal account is sketchy, but I hope you can see the rough outlines of how this story will go.
The point? That polarization is predictable does not mean that it's irrational.  Polarization found in my experiment has rational causes.

(Kevin Dorst, PhD is a philosophy professor at the University of Pittsburgh).

More News For this Category

Fire in slums does not happen it is planned

AT least 70 shanties were gutted in a fire that broke out at Natunbazar slum in the capital's Kalyanpur on Friday night. The fire which broke out at the slum

Industrialists of BSCIC Barishal industrial estate are under attacks by extortionists: Govt is powerless

A TENSE situation is prevailing at Bangladesh Small and Cottage Industries Corporation (BSCIC) Barishal industrial estate for the last one month as industry owners were coming under attack by miscreants

Gender Abuse A Severe Threat To Society

The recent series of rapes and sexual violence amid the Covid-19 pandemic has sparked widespread controversy across the country. Currently rape and sexual violence are severe threats for our society.

Child Marriage Social Stigma Or Reality?

The ongoing COVID-19 pandemic now threatens to roll back progress on ending child marriage. As children and families cope with school closures, loss of income and increased pressure in the

Students of DU-affiliated colleges should get justice as regular students

THE Covid-19 pandemic has clouded the careers of around 250,000 students of the seven colleges affiliated with Dhaka University. Uncertainty hovers upon their life with the prolonged vacation in educational

Secure and cost-effective MFS needed for banking at marginal level

A CONSUMER association has urged the authorities concerned for strengthening interoperability facility among mobile financial service (MFS) providers and demanded withdrawal of service charges. The 'Bangladesh Mobile Phone Consumer Association'

BD Expats Struggling In Bosnia Jungle

Dr. Syed Nesar Ahmad Rumy :A large number of Bangladeshi expatriates are struggling for their survival in Bosnian jungle in Balkan areas of East Europe. According to the newspapers' report

Entry Exams Universities Should Have A Fair Process

Sabuj Bhattacharjee :The coronavirus has not only harmed us physically and financially but has pushed the world of education backward for decades. Due to the outbreak of the coronavirus, there

Readers’ Voice

Excess Trans-Fat In Processed FoodTrans-fat is a type of fat which contains certain chemical properties and is usually found in manufactured food in industry such as baked food, pastry and

Alarming increase in dengue patients

The number of Aedes mosquito-borne dengue fever patients is increasing in the capital during the pandemic. In the last one week, 52 dengue patients have been admitted to different hospitals