Seven experiment designs addressing problems of safety and capacity on evaluation of warning-advisory and regulatory traffic control devices two-lane rural highways. Volume VI: experimental design for comparative.

The overuse of regulatory type signing on highways has been found to cause motorists to ignore all signing. In this experimental design, advisory-warning signs, regulatory signs and a combination of the two types will be tested in four experiments. The first experiment will compare curve signing; the second, intersection signing; the third, no passing zone signing; and fourth, signs for steep downgrades. A state-of-the-art survey and bibliography are included. A questionnaire for use in the no passing zone and downgrade experiments is appended.