Departmental news

Our next Science on the Hill event is on Tuesday 25 February, 6-8pm. We’ll delve into how different biological systems combat attacks from other organisms - highlighting the human and plant immune systems. We’ll also explore how these natural defences can inspire new therapeutics for treating patients.

Talks include ‘Defence in plants and its role in sustainability’ – Dr Emily Breeze

Find out book and book your place

Dr Emily Lane-Hill and colleagues, as part of a global research study, have developed a new biomarker test that can detect Alzheimer’s disease years before symptoms show, opening the door for earlier, more-effective, treatment.

Press Release (19 February 2025)

• A new study finds that reducing users’ exposure to toxic content on major social media platforms reduces their engagement across a variety of metrics, creating a dilemma for platforms which need engagement to survive
• Users whose feeds were filtered to reduce exposure to toxic content increased engagement with other unfiltered platforms
• Toxicity is contagious – users reading toxic posts are more likely to post their own hateful, profane or harassing content
• Profanity and hate speech have different effects on user welfare
• The study also offers insights into the benefits and limitations of automated toxicity detection.

With 5.24 billion social media accounts active around the world, decisions on what content is allowed and what should be restricted have global significance.

Social media providers are often accused of prioritising controversial content in order to maximise user engagement and increase their profits, without regard to welfare concerns for individuals or society as a whole. But the relationship between toxic content and engagement has not – until now - been proven.

In the first study of its kind, researchers from the University of Warwick, the University of Chicago and Columbia University recruited 742 volunteers to take part in a live experiment to explore how toxic content impacts user engagement on three major social media platforms.

Over six weeks in 2022, the volunteers used a custom-built browser plug-in to curate their social media feeds. During the experiment the volunteers consumed 11 million pieces of social media content across 30,000 hours of social media use.

Half the volunteers received whatever the Facebook, YouTube and Twitter algorithms served up for them. The other half received a filtered feed in which toxic content was hidden in real time. The volunteers did not know the specific way in which the browser plug-in curated their social media content.

The key findings, presented in Toxic Content and User Engagement on Social Media: Evidence from a Field Experiment, are:

• The average toxicity of text content seen by users in the moderated group was 73 per cent lower than the unfiltered group.
• Users in the moderated group engaged less across a basket of measures including time spent on the platform, ads clicked, and content consumed. For example:

• • Active time spent fell by 9 per cent on Facebook and 7 per cent on YouTube
  • Content consumed on Facebook fell by 23
  • Adverts consumed fell by 27 per cent on Facebook and by 6 per cent on Twitter
  • Ad clicks and post clicks decreased on both Facebook and Twitter

• Users in the moderated group spent on average 22 per cent more time each day on 38 other websites which were not moderated by the experiment, such as Reddit, discord, tumblr and telegram.
• Reducing exposure to toxic content reduced the average toxicity of content posted by the volunteers themselves on Facebook (by 30 per cent) and Twitter (by 25 per cent)

Dr Stalinski explains:

While this experiment is very clear that exposure to toxic content is a strong driver of social media engagement, the mechanisms behind this were less obvious.

The impact on welfare was also unclear from this first experiment. It is important not to assume that the welfare of the group who had reduced exposure to toxic content automatically improved.

To shed further light on these questions, a second online experiment asked 4,000 people to transcribe posts which varied both in their level of toxicity and the reason they had been so classified. Some posts were hateful but not profane; while others were profane but not hateful.

Dr Stalinski added:

The results of this larger study, using a different experimental design, were in alignment with our field experiment. Encountering more toxic posts increased the likelihood of clicking to see the comment sections by 18%, even though the comments were not part of the transcription task.

We also found that participants’ welfare was more adversely affected by hateful posts than profane ones. Overall, toxic posts triggered their curiosity, while profane posts specifically were also seen as more entertaining.

For the live experiment, toxic content was automatically hidden by a machine-learning algorithm trained to assess whether the content was likely to have been defined as toxic by more than 3 out of 10 human moderators. Over the six weeks of the experiment 7 per cent of posts, comments and replies met this threshold and were hidden.

The researchers note that their findings create a dilemma for social media providers. If the same approach were rolled out across the board, exposure to toxic content would fall – people would see fewer toxic posts and create fewer themselves – but engagement, ad clicks and content views would also fall, decreasing platform revenue; and users might migrate to less-moderated sites. It also does not necessarily follow that reduced toxicity enhances welfare – the welfare effects are more subtle and depend on the type of toxic content.

Dr Stalinski said:

Our evidence suggests that social media platforms’ private incentives to curtail toxicity may not be in alignment with social needs.

We therefore hope that our results will be useful to platforms, policymakers and regulators as they seek the right balance between freedom of speech and protection from harm.

We also hope that the tools to automatically detect and moderate toxic content that we experimentally assessed will be of interest to stakeholders such as social media platforms, online forums, and news sites who may wish to detect and hide toxic content in real time.

• Toxic Content and User Engagement on Social Media: Evidence from a Field Experiment. George Beknazar-Yuzbashev, Rafael Jiménez-Durán, Jesse McCrosky and Mateusz Stalinski. CAGE Working Paper 741/2025
• Download the full paper here.Link opens in a new window
• Read more about the study on the CAGE website here.

A total of five undergraduate and postgraduate programmes at WMG, University of Warwick have received accreditation from the BCS, Chartered Institute for IT.

The BCS, the professional body for computing, awarded unconditional accreditation, to the following:

Full-time courses  

· BSc Cyber Security

· MSc Cyber Security Engineering

· MSc Cyber Security Management

 Degree Apprenticeships 

· BSc Digital and Technology Solutions

· MSc Digital and Technology Solutions

This accreditation ensures that graduates from the relevant BSc and MSc programmes are automatically eligible to apply for full or partial Chartered Information Technology Professional (CITP) membership with BCS respectively, thereby enhancing their employability prospects as they embark on careers in technology and computing.

This week we are delighted to interview Professor Shaheen Ali, Professor in Islamic Law and International Human Rights, for our Warwick Law School Staff Spotlight series.

Wednesday 8th January marked the 10th anniversary of the Warwick Physics Society weekly event, PhysCafé, an event which aims to display to students some of the many options open to them once they have graduated with their Physics degree. The event has seen many different speakers, from patent lawyers to authors, company founders to bankers, and, of course, Warwick’s very own research staff.

If you are a student in Years 10-12 with an interest in Physics, you can apply for our annual 4-day work experience. Our 2025 scheme will take place from Monday 14th April to Thursday 17th April and will provide students with a broad insight into physics and what it would be like to work in a busy university physics department.

Deadline for applications is Wednesday 26th February, 4pm.

Find out more and apply.

Senn Group JACS paper reveals the impact of single-ion anisotropy, associated with concentration of JT-active sites, has on structural transition temperature in high-Tc superconductors.

"Essential reading for anyone seeking to understand the long-run evolution of the Indian economy."

In a new book published by Cambridge University Press, Professor Bishnupriya Gupta offers a major new economic history of India from the reign of Akbar in the sixteenth century to India’s post-independence integration into the global economy.

Using concepts and theories from economics and economic history alongside extensive new data, Professor Gupta builds a new framework for understanding the economic impacts and legacies of British rule. She charts India’s transition from precolonial economy to colonial rule and evaluates its economic performance from a comparative perspective, particularly in the context of the Great Divergence between Europe and Asia.

An Economic History of India examines India’s post-independence economy and the evolution of social and economic inequality through to the turn of the twenty-first century. By taking a long view, the book sheds new light on the persistent effects of historical institutions as well as the impacts of policy-driven changes.

About the Author

Bishnupriya Gupta is Professor of Economics at University of Warwick and CAGE Research Director. She has published widely on industrial development in colonial India, gender norms in India and is a key contributor to the debate on the Great Divergence.

• An Economic History of India: Growth, Income and Inequalities from the Mughals to the 21st Century can be purchased from Cambridge University Press
• Listen to Bishnupriya Gupta discuss colonialism and the economic history of India in the On Humans podcast