Machine-learning media bias

PLoS One. 2022 Aug 10;17(8):e0271947. doi: 10.1371/journal.pone.0271947. eCollection 2022.

Abstract

We present an automated method for measuring media bias. Inferring which newspaper published a given article, based only on the frequencies with which it uses different phrases, leads to a conditional probability distribution whose analysis lets us automatically map newspapers and phrases into a bias space. By analyzing roughly a million articles from roughly a hundred newspapers for bias in dozens of news topics, our method maps newspapers into a two-dimensional bias landscape that agrees well with previous bias classifications based on human judgement. One dimension can be interpreted as traditional left-right bias, the other as establishment bias. This means that although news bias is inherently political, its measurement need not be.

MeSH terms

  • Humans
  • Machine Learning*
  • Mass Media*

Grants and funding

The author received no specific funding for this work.