Discuss the below:
Epidemiologists at a medical center in the Northeast are interested in the etiology of anthracosis ("Black lung" disease), caused by the inhalation of coal dust. All the coal miners in a particlar cummunity were screened and classified according to their length of employment in the coal mines and whether symptoms of anthracosis were present.
Q: Suppose a coal miner is selected at random from this community, and his length of employment and presence or absence of symptoms are noted. a. List the simple events for this experiement. b. Let B be the event that the worker has symptoms of anthracosis. Find P(B). c. Let C be the event that the worker has spent at least 3 years in the mines. Find P(C). d. Let D be the event that the woker has spent less than 3 years in the mines and has no symptoms. Find P(D).
Table: Length of Employment
|
|
Less than 3 Years 3 years or more
|
|
Anthracosis Symptoms Present
|
18% 52%
|
|
Absent
|
24% 6%
|