Emotional Contagion — 60s explainer (A06)

01 / 08 · Setup

NEWSFEED IS US.

WE choose what we see

02 / 08 · Tension

2012 : SOMEONE CHOOSES FOR US.

Facebook Core Data Science Team

03 / 08 · Reveal

EXPERIMENTAL EVIDENCE OF MASSIVE-SCALE EMOTIONAL CONTAGION

Kramer · Guillory · Hancock · PNAS 2014

04 / 08 · Mechanism

newsfeed manipulation → emotion manipulation

Group A

more sad posts

one week · 689,003 people

Group B

more positive ones

tone of their own posts measured after exposure

05 / 08 · Scale

689,003 PEOPLE. ZERO CONSENT.

Jan 2012 experiment Jun 2014 PNAS backlash

689,003

people without consent

3 million

posts analyzed

1 week

of manipulation

06 / 08 · Discovery

JUNE 2014

PNAS

publication

Forbes

first alarm

Cornell IRB

"consent not required"

PNAS issues Editorial Expression of Concern

07 / 08 · Consequence

ZERO

formal penalties

But: a shift in the debate over "informed consent" in platform research. The start of the AI research ethics conversation.

08 / 08

EMOTIONAL CONTAGION

The first publicly documented use of 689,000 people as lab rats — without their knowledge.
Card A06 in Big Tech Files.