Attention Matters. Unfortunately.


Academic Research: Barber et al. 2022

Author: Daniel Seiler

Date: February 20, 2024

I've got to admit, I'm a fan of menus with pictures. It just makes deciding what to eat so much easier. Naturally, I often end up ordering the same thing, not because it's the best, but because the picture grabs my attention.

The impact of attention-grabbing features extends beyond restaurants to individual investors' trading behaviors and stock prices. Focusing on Robinhood, a fintech brokerage known for its app-driven trading platform, Brad Barber and his colleagues find that Robinhood investors engage in more attention-induced trading compared to other retail investors. This behavior is partly driven by the app's distinctive features, such as the prominent display of stocks that are attracting high attention.

The study reveals that intense purchasing activity by Robinhood users often predicts negative returns, with the average 20-day abnormal returns being negative. Furthermore, the paper examines the wider implications of such trading patterns on the financial markets.


What are interesting findings?
  • In simple terms, the study shows that even though Robinhood users usually don't make big changes to their investments, sometimes a lot of them will buy or sell the same stocks at the same time. This often happens when new investors, who are more likely to take risks and go after the latest hot topic, all follow the same trend. This behavior shows that investors can be really influenced by what's getting the most attention.
  • When lots of investors all focus on a few stocks, they can end up following each other like a herd. This can actually make stock prices go up or down, which isn't necessary good for investors. The study from the document reveals that on average, investors experience negative abnormal returns following herding events, particularly among Robinhood users. Specifically, after a period of intense buying of certain stocks by Robinhood users, the average abnormal returns over a 20-day event period were found to be negative.
  • It shows that having the right information isn't enough; it also matters how people see and use that information. How information is shared can really help or hurt investors' choices.
  • For everyday investors using apps like Robinhood, this study shows it's crucial to watch out for the tendency to just follow the crowd and how much attention a stock is getting. It's important to be careful with how you use information and make investment choices, especially to avoid jumping on trends without really understanding what you're investing in.

Why is it important for us?

The paper really grabs my attention with its look at how technology changes the way we decide to invest. It shows that apps can sway how investors act, which makes you wonder if we're not as rational as we think.

It points out that easy-to-use trading apps can make investors all move together, just based on what stands out to them, not on detailed research. It makes me curious if the same thing happens on expert platforms like Bloomberg.

The big takeaway is that while trading technology opens up the market for more people, it also means we have to work harder to make sure we're making smart choices.

Even for those of us investing in big market ideas, the study is a heads-up. It reminds us to stick to real analysis and not get sidetracked by the flashy stuff and non-stop news.