In this video, I explain two well-known examples of observer bias: the case of Clever Hans, and Rosenthal and Fode’s experiment with “bright” and “dull” rats. Observer bias (or experimenter expectancy effect) is considered, along with an explanation for how … Read More
Was Hans really Clever?
Here’s a good video summary of the case of Clever Hans and how Oskar Pfungst was able to figure out that Wilhelm von Osten was inadvertently signaling answers to Hans. And even though Hans wasn’t actually doing mathematics, he was … Read More