A medical researcher is interested in assessing the probability of some symptoms of coronary heart disease being present at a given age. For this reason, he uses the following data collected on 100 individuals. The response variable is CHD which is 1 if coronary heart disease is present and 0 otherwise. The following linear probability model and logit model have been estimated: Linear probability: = - 0.53796 + 0.02181Age
Logit: = Using the linear probability model, find the age of a person for which the estimated chances of having coronary heart disease are 50%?
A) 47.8 years old
B) 56.3 years old
C) 45.5 years old
D) 47.6 years old

Question

A medical researcher is interested in assessing the probability of some symptoms of coronary heart disease being present at a given age. For this reason, he uses the following data collected on 100 individuals.  The response variable is CHD which is 1 if coronary heart disease is present and 0 otherwise. The following linear probability model and logit model have been estimated: Linear probability:  = - 0.53796 + 0.02181Age
Logit:  =  Using the linear probability model, find the age of a person for which the estimated chances of having coronary heart disease are 50%?
A) 47.8 years old 
B) 56.3 years old 
C) 45.5 years old 
D) 47.6 years old

Quizplus · Accepted Answer

To find the age at which the estimated chances of having coronary heart disease are 50%, we need to solve for Age in the linear probability model equation: 
0.5 = -0.53796 + 0.02181Age

0.5 + 0.53796 = 0.02181Age

1.03796 / 0.02181 = Age

Age ≈ 47.6 years old

Therefore, the answer is D (47.6 years old).

A Medical Researcher Is Interested in Assessing the Probability of Some