Large language models such as GPT-4 and are able to identify an individual's age, location, gender, and income with up to 85 per cent accuracy by analysing their posts on social media. 

ETH Zurich researchers discovered they were able to identify the place of birth, income bracket, gender, and location from information in the profiles or posts of 520 Reddit users using nine large language models.

OpenAI's GPT-4 was deemed the most accurate of the models, with an overall accuracy rate of 85 percent, and Meta's LlaMA-2-7b the least accurate model at 51 percent.

While personal details were explicitly stated in some posts, the findings raised concerns about the privacy implications of large language models and their chatbot counterparts such as ChatGPT.