Experimental Design Concepts

The video introduces the concept of experiments, focusing on the relationship between explanatory and response variables. It emphasizes the importance of a well-designed experiment to eliminate ambiguity and ensure clear results. Through examples, it illustrates how to control extraneous variables using direct control, blocking, and randomization. The video also provides guidance on planning experiments, highlighting key questions to consider.

What is the primary purpose of conducting an experiment?

• To collect random data

• To test a new theory

• To observe the effects of explanatory variables on a response variable

• To prove a hypothesis

Why is it important to have a good design for an experiment?

• To ensure the experiment is completed quickly

• To make the experiment more interesting

• To minimize ambiguity in interpreting results

• To reduce the cost of the experiment

In the classroom temperature experiment, what is considered an extraneous variable?

• The subject of the test

• Student's test score

• Room temperature

• Time of day the test is taken

What is the purpose of using blocking in an experiment?

• To increase the sample size

• To control for one extraneous variable at a time

• To ensure all participants receive the same treatment

• To make the experiment more complex

In the waitress tip experiment, what is the explanatory variable?

• The percentage of the tip

• The amount of the bill

• Whether 'thank you' is written on the bill

• The day of the week

What is a potential confounding variable in the grass-growing experiment?

• Type of fertilizer used

• Amount of water given

• Amount of sunlight received

• Type of grass seed

Which of the following is NOT a question to consider when planning an experiment?

• What is the budget for the experiment?

• How will the data be analyzed?

• What are the factors and treatments?

• What is the research question?