What do you understand by selection bias and mention its types?

Selection bias is a type of error that crops up when the researcher is deciding who/what is going to be studied. It is usually associated with research whose selection of participants is not random.

It is sometimes also mentioned as the selection effect. It involves the distortion of statistical analysis, which is a result of the method of collecting samples. It is vital to the whole process as, without this, the conclusions may not be accurate.

Here are the types of selection bias:

• Sampling bias
• Time interval Bias
• Data Bias
• Attrition Bias