Dillman, Smyth, and Christian (2014) underscore that the researcher needs to avoid four types of errors as cornerstones of good quality surveys.
• Coverage error, which refers to drawing samples form a list of irrelevant samples to represent the population
• Sampling error, which exists any time when the researcher reaches some of the sample and not all members. For instance, instance, to understand the attitudes of political participation of university students the researcher only randomly selects students from one province as the available population rather than the whole country to generalize the findings to the target population;
• Nonresponse error, which occurs when some particular units of analysis tend to answer some particular items which are likely to influence the estimate of the findings;
• Measurement error is described as the difference between the estimate produced and the true value in case the respondents may answer inaccurately to the survey questions.