We adopted the same methodology in counting the number of marchers in Sunday's anti-Occupy Central march as we did for the July 1 rally. Our 12-member team was on duty from 2pm to 6pm that day.
Besides counting heads, we also conducted interviews at random. Obviously, participants moved much faster than those on July 1 as there were no obstructions or delays caused by disagreements between the organiser and the police.
The peak and average flow rates were 400 and 250 people per minute respectively. We estimated that the total number of people marching was about 57,000. Police gave an estimate of 112,000 at Victoria Park.
The discrepancy between the two figures may be explained by the possibility that a substantial number of participants left the march at the starting point at Victoria Park, or nearby, after the march commenced. As they did not pass our two observation points in Causeway Bay and Admiralty, they were not included in our headcount.
The marchers on Sunday were very different from those of July 1. Nearly 80 per cent of Sunday's marchers wore some sort of uniform and they appeared to be well organised.
Many were older people and some were not Hongkongers. The majority did not understand our interviewers' questions or simply refused to answer.
The organiser says the event illustrates massive opposition to the Occupy Central movement. I doubt this. Despite the concerted effort to boost turnout, Sunday's march was still a lot smaller than the July 1 rally (57,000 versus 122,000, based on our estimates).
And what have they achieved? It created a lot of noise, but the voice of the so-called "silent majority" has not been heard. To resolve divisions over the 2017 chief executive election, we cannot rely on a combative, tit-for-tat approach that drives people to extremes and further tears the community apart. It may lead Hong Kong people into a vicious, downward vortex from which we will be unable to extricate ourselves.
While national security and social stability are important given domestic unrest and disputes between China and her neighbours, a fair, just, reasonable election in 2017, abiding by the Basic Law, cannot be disregarded either.
It is not simply a matter of a war of opinion or a public-relations exercise but a genuine call for improvement in our chief executive election process, which is an aspiration of the majority of Hong Kong people.
Hong Kong's governance will not improve if the present election arrangement continues or is replaced by another system which is unacceptable to the majority of Hong Kong people.
Hong Kong would then be a headache to our country rather than a constructive contributor to the mainland's development. Inclusion and embracing diversity are the ways to go.
Exaggerating the number of participants in a rally serves no useful purpose. Even a large turnout does not help resolve conflicts or provide solutions. Using inaccurate numbers achieves nothing, but it misleads people, misjudges the situation and discredits the source.
Numbers are neutral. Counting numbers accurately in a mass movement is a science. Let's not fool ourselves or others. Accurate information is essential to help understand the complexity of our community.
If we aim to resolve problems, try to deal with the root of the problem and let the facts speak for themselves.
Paul Yip Siu-fai is a professor of social work and social administration at the University of Hong Kong