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In Walter Mischel's marshmallow studies at Stanford around 1970, preschoolers who waited longer for a second treat, instead of eating the first at once, tended to do better years later. A 2018 study of a much larger and more varied group found the link about half as strong, and weaker still once family background was counted.

Walter Mischel (1970s); Tyler Watts, Greg Duncan & Haonan Quan, 2018 replication

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Mischel's studies ran at Stanford's Bing Nursery School with a few dozen children each, mostly from well-off university families. In 2018 Tyler Watts, Greg Duncan and Haonan Quan used data on more than 900 children from a large US government-funded study, focusing on those whose mothers had not finished college. Waiting at age four still predicted school results at 15, but the link shrank by about two-thirds once they accounted for family background, early ability and home environment. Circumstances matter too: in a 2013 study at the University of Rochester, children who had just seen an adult break a promise waited about 3 minutes, against about 12 for those whose adult had kept it.

Türkçe oku
Walter Mischel'in 1970 civarında Stanford'da yaptığı marshmallow deneylerinde, şekerlemeyi hemen yemeyip ikincisi için daha uzun bekleyen okul öncesi çocuklar yıllar sonra genellikle daha iyi durumdaydı. 2018'de çok daha kalabalık ve çeşitli bir grupla yapılan araştırma bu bağı yarı yarıya zayıf buldu; aile koşulları hesaba katılınca bağ daha da zayıfladı.

Mischel'in deneyleri Stanford'un Bing Anaokulu'nda, her seferinde birkaç düzine çocukla ve çoğunlukla varlıklı üniversite ailelerinin çocuklarıyla yapıldı. Tyler Watts, Greg Duncan ve Haonan Quan 2018'de, ABD devletinin finanse ettiği büyük bir araştırmadaki 900'ü aşkın çocuğun verilerini kullandı; özellikle anneleri üniversite bitirmemiş çocuklara odaklandı. Dört yaşında bekleyebilmek 15 yaşındaki okul başarısını yine öngörüyordu, ama aile koşulları, erken yaştaki beceriler ve ev ortamı hesaba katılınca bağ yaklaşık üçte bir düzeyine indi. Koşulların etkisini başka araştırmalar da gösteriyor: Rochester Üniversitesi'nde 2013'te yapılan bir çalışmada, az önce bir yetişkinin sözünü tutmadığını gören çocuklar ortalama 3 dakika, sözü tutulan çocuklar ise yaklaşık 12 dakika bekledi.

Sources and further reading

Background reading: Stanford marshmallow experiment
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