Credit: Public domain.
Political polls in South Korea tend to become volatile around election time, often with wide discrepancies showing up in the results of different polls. Approaching an intra-party election, for example, it is common for polls to show a significant jump in support for the party holding the election, even without substantial changes in external conditions.
This phenomenon was visible in the significant increase in support for the People Power Party 국민의힘 in the first two weeks of February, ahead of the PPP’s leadership election on March 8. Part of the reason for the jump is because the supporters of that party are more activated as they focus on politics, making them more willing to answer calls from pollsters on whom they might otherwise have hung up.
But sometimes, the jump in support occurs for a less innocuous reason. According to a Korea Economic Daily 한국경제 article on February 8, a group of PPP supporters mass-forwarded a text message: “If an opinion poll phone call asks your age, say you are in your 20s. If you say you are in your 60s, they will not take your answer.”
The instruction is intended to game poll sampling, which attempts to gauge public opinion by creating a sample group that reflects broader social demographics. In many cases, particularly with opinion polls that rely on automated phone calls rather than live caller interviews, polling companies stop collecting data once enough people in a certain demographic - for example, people over 60 - have responded. This particularly affects the PPP, whose supporters tend to be older.