How do election surveys work?

Survey results from research institutions like Pulse Asia and Social Weather Stations frequently make the headlines—especially during the election period, when they show which candidates are likely to make it to the winner's circle.

But to what extent does the public understand survey methodology?

In the video above, GMA's resident political analyst Professor Richard Heydarian explains how surveys work—including sampling methods and margins of error—and answers one of the most frequently asked questions about these polls: how does the preference of a relative few reflect the sentiments of the much larger population as a whole? — BM, GMA News