What is the importance of having a selection bias?
Ideally, you should randomly select every participant in a survey. But, sometimes biases creep in, whether intentional or unintentional. Selection bias takes away from the “randomness” you are hoping to achieve. It’s usually a result of not using the correct procedures to choose your participants. Types of selection bias include: the healthy worker effect, non-response bias, undercoverage, and voluntary response bias.