"The papers describe the observations of 1,327 nearby stars, fast radio bursts, and pulsar searches."
There are around 200,000,000,000 stars in the Milky Way. If there is a one in a million chance of a star having a planet with an advanced civilization, the chance for success with 1,327 stars would be around 0.13%. Conversely, there could be 200,000 advanced civilizations in the Milky Way.....