Question

A researcher observes that, on average, the number of divorces in cities with major league baseball teams is larger than in cities without major league baseball teams. The most plausible explanation for this observed association is

A) The presence of a major league baseball team causes the number of divorces to rise.

B) The high number of divorces is responsible for the presence of a major league baseball teams.

C) The association is due to the presence of a lurking variable (major league teams tend to be in large cities with more people, hence a greater number of divorces).

D) The observed association is purely coincidental. It is implausible to believe the observed

association could be anything other than accidental.

Answer 1

This is a case of spurious correlation which is defined as the relation of some association between 2 variables that appears causal but it is not. This is often caused by a third variable that is affecting both the other variables which is happening in this case.

Generally the major league teams are from larger cities and in larger cities, there is a greater population and so the absolute number of divorces would also be higher (we are not talking about divorce proportion but absolute number of divorces. )

Therefore c) is the correct answer here. The association is due to the presence of a lurking variable (major league teams tend to be in large cities with more people, hence a greater number of divorces).