Social media sites and search engines have become the de facto gatekeepers of public
communication, a role once occupied by publishers and broadcasters. With this new role come
public responsibilities, including limiting the spread of misinformation.

Externally maintained metrics offer a way to measure the progress of media platforms at
meeting their public responsibilities. By contrast with the current environment of accountability
by anecdotes, Platform Health Metrics can focus attention on the overall performance of
platforms rather than on bad outcomes in individual cases.

The Center for Social Media Responsibility at the University of Michigan School of Information
has developed the Iffy Quotient, a metric for how much content from “Iffy” sites has been
amplified on Facebook and Twitter. We use the term “Iffy” to describe sites that frequently
publish misinformation. It is a light-hearted way to acknowledge that our categorization of the
sites is based on imprecise criteria and fallible human judgments. We are publishing a
web-based dashboard that charts the Iffy Quotient since early 2016. The dashboard enables
comparisons over time and between platforms. This report describes the calculation of the Iffy
Quotient in detail, discusses some of its potential limitations, and analyzes some of the trends.

In 2019, we changed the methodology for calculating the Iffy Quotient. We now deem a site as
Iffy or OK based on ratings from NewsGuard, falling back on rating from Media Bias/Fact Check
only for sites not rated by NewsGuard. In addition, because NewsGuard has higher coverage of
sites that were popular in 2019 than those in 2016, and for sites that were popular on Facebook
than those that were popular on Twitter, we now define the Iffy Quotient as the fraction of URLs
from rated sites rather than the fraction of URLs from all sites. This has increased the absolute
values of the Iffy Quotient on particular days in comparison to our version 1 numbers, but the
trends over time remain largely unchanged.

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