Vaccine hesitancy is a complex issue with psychological, cultural, and even societal factors entangled in the decision-making process. The narrative around this process is captured in our everyday interactions; social media data offer a direct and spontaneous view of peoples' argumentation. Here, we analysed more than 500,000 public posts and comments from Facebook Pages dedicated to the topic of vaccination to study the role of moral values and, in particular, the understudied role of the Liberty moral foundation from the actual user-generated text. We operationalise morality by employing the Moral Foundations Theory, while our proposed framework is based on recurrent neural network classifiers with a short memory and entity linking information. Our findings show that the principal moral narratives around the vaccination debate focus on the values of Liberty, Care, and Authority. Vaccine advocates urge compliance with the authorities as prosocial behaviour to protect society. On the other hand, vaccine sceptics mainly build their narrative around the value of Liberty, advocating for the right to choose freely whether to adhere or not to the vaccination. We contribute to the automatic understanding of vaccine hesitancy drivers emerging from user-generated text, providing concrete insights into the moral framing around vaccination decision-making. Especially in emergencies such as the Covid-19 pandemic, contrary to traditional surveys, these insights can be provided contemporary to the event, helping policymakers craft communication campaigns that adequately address the concerns of the hesitant population.

1. Moral Narratives Around the
Vaccination Debate on Facebook
Mariano Gastón Beiró, Jacopo D'Ignazi, Maria Florencia Prado, Victoria Perez Bustos,
Kyriaki Kalimeri

3. Which moral narratives are prioritised by
vaccine supporters and which by hesitants?

4. Care/Harm: virtues of caring and compassion.
Fairness/Chea
ti
ng: unfair treatment, inequality, no
ti
ons of jus
ti
ce.
Loyalty/Betrayal: obliga
ti
ons of group membership, loyalty, vigilance against
betrayal.
Authority/Subversion: social order, obliga
ti
ons of hierarchical rela
ti
onships
such as obedience, respect
Purity/Degrada
ti
on: physical and spiritual contagion,
virtues of chas
ti
ty, wholesomeness and control of desires.
Liberty/Oppression: feelings of reactance and resentment people feel toward
those who dominate them and restrict their liberty
Moral Foundations Theory

5. Data Collection
Vocal Minority
Hesitant post are
fewer (almost half)
but generated
double the volume
of comments.
Period: 2012 - 2019
Manual Annotation
of ~5.000 comments
.78 Cohen Kappa
AV: Umbrella term for Hesitancy

6. Methods
Relevance Classi
fi
er
basic NLP preprocessing
Glove Embeddings
Entity Recognition TagMe
bidirectional LSTM
Dropout & 10fold cross validation
Moral Classi
fi
er
basic NLP preprocessing
Glove Embeddings
bidirectional LSTM
Dropout & 5fold cross validation

7. Stance Classification
Reported metrics are average AUROC

8. Moral Classification
Presence
Liberty is the most
performant
Value
Authority is the the most
stable one
Loyalty prediction improves
Reported metrics are average AUROC

9. Moral Narratives
Prioritise:
Liberty - Freedom of Choice
Purity - Holistic Therapies
“It will take a massive class action lawsuit against big pharma
AND Congress to stop the forced vaccinating.”
“None of my children is vaccinated and I only use homeopathy for our
health. It is very di
ffi
cult for me to trust conventional medicine”
Higher Trust in Authorities
More concerned about protecting others
“I have worked in school nursing for 15 years. We DO NOT bully anyone.
We educate on state guidelines as well as available exemptions.”

10. Take Home Message
Understanding view points help bridge societal polarisation
Generalisable approach to any kind of textual data
Insights on a wide range of social phenomena

11. Reach out!
Kyriaki Kalimeri
kyriaki.kalimeri@isi.it
@KyriakiKalimeri
Moral Narratives Around the
Vaccination Debate on Facebook
Mariano Gastón Beiró, Jacopo D'Ignazi, Maria Florencia Prado, Victoria Perez Bustos, Kyriaki Kalimeri