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## Statistics and probability

### Course: Statistics and probability>Unit 6

Lesson 5: Experiments

# The language of experiments

Karina wants to determine if kale consumption has an effect on blood pressure. She recruits $100$ households and randomly assigns each household to either a kale-free diet plan or a kale-based diet. At the end of two months, she plans to record the original and final blood pressures for members of each household.
Problem 1
What is the explanatory variable?

problem 2
What is the response variable?

Problem 3
What are the treatments?

problem 4
Who or what are the experimental units?

## Want to join the conversation?

• Why wouldn't the answer for problem 4 be the members of each household?
• The members of each household receive the same diet, but each household could have a different diet. Since the diet is consistent in the household, the household is the experimental unit.
• Words are slippery. The last question expects as correct answer the households, not their members. Makes me scratch my head and and ironically conclude: "Aha! So it is the households who eat (or not) the kale, not the household members".
• That is a funny point, but the household is the whole of the household members. We were comparing different households as a whole and not a households individual members.

Hope this helps,
- Convenient Colleague
• why didnt seattle just run the ball..
• It was the right call but Malcolm Butler just made a great play.
• If the household members are not the experimental units, then what are they?
• What can be the possible source of bias here ?