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In a one-week experiment in 2012, Facebook and university researchers cut some positive or negative posts from the News Feeds of 689,003 users, without telling them; control groups had random posts hidden instead. The emotional words in users' own posts then shifted slightly in the same direction.

Adam Kramer, Jamie Guillory & Jeffrey Hancock, PNAS, 2014

MindTechnology

The story behind the card

Emotional contagion is the idea that moods spread from person to person, as when a friend's cheerfulness lifts your own. This study, by Facebook's Adam Kramer and researchers linked to Cornell University, measured mood only by counting emotional words, and the shift was tiny: when negative posts were cut, users' own posts contained about 0.07 percentage points fewer negative words. The larger debate was about consent. Users had agreed only to Facebook's general terms of service; they were never told about the experiment or offered a way out. After the paper appeared in the journal PNAS in 2014, criticism from scientists and the public led the journal to publish an “Editorial Expression of Concern”, a formal note that questions how a study was carried out without withdrawing it.

Türkçe oku
Facebook ve üniversite araştırmacıları 2012'deki bir haftalık deneyde, 689.003 kullanıcıya haber vermeden akışlarından bazı olumlu ya da olumsuz paylaşımları çıkardı. Kontrol gruplarında rastgele paylaşımlar gizlendi. Ardından kullanıcıların kendi paylaşımlarındaki duygu yüklü sözcükler de aynı yönde biraz değişti.

Duygusal bulaşma, bir arkadaşınızın neşesinin sizi de neşelendirmesi gibi, ruh hâlinin insandan insana geçmesine denir. Facebook'tan Adam Kramer ile Cornell Üniversitesi'ne bağlı araştırmacıların yaptığı bu çalışma, ruh hâlini yalnızca duygu içeren sözcükleri sayarak ölçtü ve değişim çok küçüktü: Olumsuz paylaşımlar azaltıldığında, kullanıcıların kendi yazdıklarındaki olumsuz sözcük oranı yaklaşık 0,07 yüzde puan düştü. Asıl tartışma onay üzerineydi. Kullanıcılar yalnızca Facebook'un genel kullanım koşullarını kabul etmişti; deneyden haberleri yoktu ve dışında kalma seçenekleri de sunulmadı. Makale 2014'te PNAS dergisinde yayımlanınca bilim insanlarından ve kamuoyundan yoğun eleştiri geldi. Dergi de bir “Editoryal Kaygı Bildirimi” yayımladı: Makaleyi geri çekmeden, araştırmanın nasıl yürütüldüğüne dair ciddi kuşkuları kayda geçiren resmî bir not.

Sources and further reading

Background reading: Emotional contagion
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