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Chapter 3: Q R3.1. (page 198)

The risks of obesity A study observes a large group of people over a 10-year period. The goal is to see if overweight and obese people are more likely to die during the study than people who weigh less. Such studies can be misleading because obese people are more likely to be inactive

and poor.

(a) What are the explanatory and response variables in the study?

(b) If the study finds a strong association between these variables, can we conclude that increased

weight causes a greater risk of dying? Why or why not?

Short Answer

Expert verified

Part (a) The probability is 0.875

Part (b) No.

Step by step solution

01

Part (a) Step 1: Given information

Obese people are more likely to die than persons who weigh less, according to a study. Obese people are lethargic and lazy, which could be a confounder.

02

Part (a) Step 2: Concept

Relationships between variables can be described as null, covariant, or influential.

03

Part (a) Step 3: Explanation

Because it is reliant on the people's weight, the death rate is the response variable in this situation. As a result, mortality rate is a response variable, while weight is an explanatory variable.

04

Part (b) Step 1: Explanation

It is impossible to say that obesity causes an increase in the risk of death because other factors such as activity and affluence might influence weight and mortality rates. As a result, it is impossible to concur with the given statement.

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