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Observer-expectancy effect 0:50
A 50-second explainer of Observer-expectancy effect, narrated over the same demo you can try yourself.
Try the interactive Observer-expectancy effect demo
What this video covers
The observer-expectancy effect is when a researcher's own hopes and expectations leak into a study and shape its result - through how they word a question, react to an answer, or interpret what they see. You go in wanting your design to win, and without meaning to, you nudge participants toward agreeing and read ambiguous behaviour in your favour.
As the leading facilitator, you practically handed the participant the answer - "wasn't that easier?" - and of course they agreed. As the neutral one, you asked "how did that feel?" and got the truth, warts and all. Same participant, same task; the only variable was how much of your own hope you let into the room.
