[glimcat]

He's claiming that spacing is the dependent variable, not the independent variable.

Parents who are not considering these issues at all are arguably more likely to cluster towards shorter spacings, but shorter spacings alone do not provide enough information to classify the cause.

[andrewhare]

Good point! I just wanted to make sure that the OP knew that he was too sweeping in his generalizations.

[inuhj]

It wasn't too sweeping--I purposefully said nothing about what responsible parents do ;).