For those who have taken the IAT test:
The IAT is based on research of sociology, psychology, and cognitive behaviors... I see some people are very discomforted by the test and the classification... But we do this subconsciously every day, every second. Not to be prejudice or bias, but our brains are wired to make 'quick assessments' of things so we can proccess, evaluate, and response/behave appropriately based on past experiences, learned models, and scripts.
An example I remember from my studies includes a child learning what a horse is... categorization is a way we make these quick assumptions. A child sees a horse in the field, she quickly states that this animal is a dog. Based on the features that we previously know about dogs (four legs, long nose, tail, etc.) the girl makes this assumption. A correction is made and from there on the girl knows that the horse is bigger than a dog and can separate that classification.
I see this happening when people are describing anyone Asian. Like in the video, people only catagorize "chinese" or "japeneese".