https://www.youtube.com/watch?v=_Nza20_l5qQ watch the posted video on "Clever Hans." In your response to this video you should consider the following:

What aspects of scientific experiment design cause you to be skeptical of Von Osten's claim that Clever Hans has mathematical abilities?

Imagine that you were testing a horse with supposed mathematical abilities like Clever Hans'. What procedures could you use to control for the issue of the experimenter expectancy effect?

Why is the experimenter expectancy effect an important issue to consider when conducting experimental research?

What are some of the specific strategies researchers can take to control for the experimenter expectancy effect?