A city corporation opened a telephone line on which residents might record whether the corporation should begin charging for parking on the main road, and reports that of the 3,100 who recorded a view, 82 in every hundred were against the charge. An answer to which of the following questions would be of most use in judging what the 3,100 tell the corporation about the city's residents?

The line was open to everybody and answered by whoever cared to answer, so the 3,100 are held together by their own willingness to telephone. If that willingness runs with keeping a car and parking it daily on the very stretch to be charged, then the 82 in a hundred measures the resistance of those who would pay and tells the corporation nothing about the residents who walk or ride and would only gain by a clearer road. The question asked puts precisely that to the test. The cost of the line and the committee that proposed the charge bear on the corporation's own working; the number of shops on the stretch bears on who else is affected. None of the three tells us whether the callers stand for the city.