Sophia Introduction to Statistics Unit One Milestone One

A trainer is studying the effects of vitamin D on his athletes. He has realized that there are many potential confounding factors, such as gender and age. To limit the effect of these confounding variables, he decided to first group two athletes together based on these variables (for example, two 21-year-old males). Then he randomly assigned one person to receive the vitamin D and the other to receive a sugar pill. What type of experimental design does this situation demonstrate? Completely Randomized Design Randomized Block Design Matched-Pair Design Simple Random Design RATIONALE By matching on age and gender this is called a matched-pair design. CONCEPT Matched-Pair Design 6/26/2020 Sophia :: Welcome 2 A team of researchers want to measure the distance covered while driving compared to a car's driving speed. Which statement is correct? The speed of the car is a dependent variable. The speed of the car is a confounding variable. The speed of the car is an explanatory variable. The speed of the car is a response variable. RATIONALE The outcome is the response, dependent or y -variable. The variable that explains the response is the explanatory, independent or x-variable. In this case the explanatory variable is speed with distance being the response. CONCEPT Variables 3 Melissa is conducting a survey of her classmates because her teacher wants the class to learn more about hygiene habits. Melissa has developed a list of 10 questions. “Do you brush your teeth every day?” is the first question she asks. Which type of question is Melissa asking?