than ever before to perfecting the schedules and weighing each question
with regard to its precise significance and scientific value. To that
end a group of trained investigators, familiar with the various topics
which the census would cover, spent several months on a preliminary
study of the character of these questions. In addition to the
nationality of each person as determined by the mother tongue of the
foreign-born inhabitants, additional inquiries were made relative to the
industry in which each person was employed and whether the person was
out of work on April 15.
