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The frequency illusion is the feeling that something you have just noticed, such as a new word, a car model or a name, has suddenly started turning up everywhere. Usually it was always there; what has changed is your attention.

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The effect got its popular name in 1994, when a reader of the St. Paul Pioneer Press in Minnesota wrote to the paper that, after first hearing of the Baader-Meinhof group, a West German militant organisation, he kept coming across the name. Other readers sent in similar stories, and 'Baader-Meinhof phenomenon' stuck as a nickname. In 2005 the Stanford linguist Arnold Zwicky named it the frequency illusion and explained it with two ordinary mental habits. Selective attention means the brain filters out most of what we see and hear but lets through whatever has recently become important to us. Confirmation bias means we then treat each new sighting as proof and forget the days we saw nothing. Zwicky also described a related recency illusion: assuming that a word or usage you have only just noticed must be new, when it is often much older.

Türkçe oku
Sıklık yanılsaması, yeni fark ettiğin bir şeyin birden her yerde karşına çıkıyormuş gibi gelmesidir: yeni bir sözcük, bir araba modeli ya da bir isim. Çoğu zaman o şey hep oradaydı; değişen, senin dikkatin.

Bu olgu yaygın adını 1994'te aldı. ABD'nin Minnesota eyaletinde çıkan St. Paul Pioneer Press gazetesinin bir okuru, Batı Almanya'daki silahlı Baader-Meinhof örgütünün adını ilk kez duyduktan sonra sürekli karşısına çıktığını yazdı. Başka okurlar da benzer deneyimlerini gönderdi ve “Baader-Meinhof fenomeni” adı yerleşti. 2005'te Stanfordlu dilbilimci Arnold Zwicky olguya sıklık yanılsaması adını verdi ve onu iki sıradan zihin alışkanlığıyla açıkladı. Birincisi seçici dikkattir: Beyin gördüğün ve duyduğun şeylerin çoğunu süzüp atar, ama o sırada senin için önem kazanmış olanı içeri alır. İkincisi doğrulama yanlılığıdır: Her yeni karşılaşmayı kanıt sayarsın, hiç rastlamadığın günleri ise unutursun. Zwicky buna yakın bir yanılgıya da ad verdi: yenilik yanılsaması. Yeni fark ettiğin bir sözcüğün ya da kullanımın yeni çıktığını sanırsın; oysa çoğu zaman çok daha eskidir.

Sources and further reading

Background reading: Frequency illusion
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